Biological Opinion

for Effects to Northern Spotted Owls (Strix occidentalis caurina)

from the Willamette Planning Province Fiscal Year 2006 – 2007 activities

that have the potential to adversely affect, due to disturbance,

on U.S. Department of the Interior;

Bureau of Land Management, Eugene District and Salem District,

 and the U.S. Department of Agriculture;

Mt. Hood National Forest, Willamette National Forest

and the Columbia River Gorge National Scenic Area

(FWS Reference Number 1-7-05-F-0663)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Prepared by the Oregon Fish and Wildlife Office

of the U.S. Fish and Wildlife Service

Portland, Oregon

 

 

 

 

 

 

_________________________________

Kemper M. McMaster, State Supervisor

 

_________________________________

Date

 

 

 

TABLE OF CONTENTS

LIST OF TABLES. 5

LIST OF FIGURES. 5

INTRODUCTION.. 6

CONSULTATION HISTORY.. 6

BIOLOGICAL OPINION.. 7

1.0 Description of the Proposed Action.. 7

1.1 Definitions. 7

1.1.1 Spotted Owl 8

1.1.2 Bald Eagle. 8

1.1.3 Disturbance/Disruption distances. 8

1.2 Management Standards. 13

1.2.1 General 13

1.2.2 Specific to the Bald Eagle. 13

1.2.3 Specific to the Spotted Owl 13

1.3 Action Area. 15

2.0 Status of the NORTHERN SPOTTED OWL. 16

2.1 Legal Status. 16

2.2 Life History. 16

2.2.1 Taxonomy. 16

2.2.2 Physical Description. 16

2.2.3 Current and Historical Range. 16

2.2.4 Behavior 17

2.2.5 Habitat Relationships. 17

2.2.6 Reproductive Biology. 19

2.2.7 Dispersal Biology. 19

2.2.8 Food Habits. 20

2.2.9 Population Dynamics. 21

2.3 Threats. 21

2.3.1 Reasons for Listing. 21

2.3.2 New Threats. 22

2.4 Conservation Needs of the Spotted Owl 27

2.4.1 Habitat-specific Needs. 27

2.4.2 Habitat-independent Needs. 28

2.4.3 Conservation Strategy. 28

2.4.4 Federal Contribution to Recovery. 28

2.4.5 Conservation Efforts on Non-Federal Lands. 29

2.5 Current Condition of the Spotted Owl 30

2.5.1 Range-wide Habitat and Population Trends. 30

3.0 Bald Eagle. 40

3.1 Analysis of the bald eagle likely to be affected. 41

4.0 Environmental Baseline. 41

4.1 Spotted Owl 41

4.1.1 Central Cascade Study Area. 43

4.1.2 NWFP. 43

4.1.3 Role of the Action Area in the Survival and Recovery of the Spotted Owl 44

5.0 Effects of the Action.. 45

6.0 EFFECTS TO SPECIES. 45

6.1 Spotted Owls. 45

6.1.1 Effects to Spotted Owl Habitat 45

6.1.2 Disturbance Effects. 45

7.0 Effects of the Action BY ACTIVITY TYPE. 49

7.1 Aerial Fertilization and Seeding. 49

7.1.1 Spotted owl 50

7.2 Aerial Operations – Other 50

7.2.1 Spotted owl 50

7.3 Blasting. 51

7.3.1 Spotted owl 51

7.4 Campgrounds/ Picnic areas/ Administrative Sites/Trail heads - Heavy Operations and Maintenance  51

7.4.1 Spotted Owl 52

7.5 Firewood/Post and Pole Sales. 52

7.5.1 Spotted Owl 52

7.6 In-stream Activities/Terrestrial Habitat Restoration. 53

7.6.1 Spotted owl 53

7.7 Invasive Plant Control 53

7.7.1 Spotted owl 53

7.8 Miscellaneous Special Uses (High Intensity) 54

7.8.1 Spotted owl 54

7.9 Power Line Maintenance. 54

7.9.1 Spotted owl 55

7.10 Precommercial thinning/stand maintenance/ riparian site preparation. 55

7.10.1 Spotted owl 55

7.11 Prescribed Burning. 56

7.11.1 Spotted owl 56

7.12 Road and Dike Repair 57

7.12.1 Spotted owl 57

7.13 Rock Quarry Sites and Operations. 57

7.13.1 Spotted owl 57

7.14 Salvage. 58

7.14.1 Spotted owl 58

7.15 Special Forest Products. 59

7.15.1 Spotted owl 59

7.16 Trail Reconstruction, Maintenance, and Removal 59

7.16.1 Spotted owl 59

7.17 Summary of affects. 60

7.17.1 Spotted owls. 60

8.0 COMBINED Effects to the populations. 60

8.1 Willamette Planning Province. 60

8.2 Oregon Western Cascades Physiographic Province. 60

8.3 Oregon Eastern Cascades Physiographic Province. 60

8.4 Range-wide. 61

8.5 Relationship of affects to survival and recovery of the spotted owl 61

9.0 Cumulative Effects. 61

10.0 Conclusion.. 62

11.0 Amount or Extent of Take. 63

12.0 Reasonable and Prudent Measures. 63

13.0 Terms and Conditions. 63

14.0 Conservation Recommendations. 63

15.0 Reinitiation Notice. 63

LITERATURE CITED.. 64

 

 


LIST OF TABLES

Table 1.  Proposed activities in the Willamette Province divided by Northwest Forest Plan Land Use Allocations.  Shaded areas indicate land allocations where the noted activity is not addressed by this biological opinion. 9

Table 2.  Descriptions of activities proposed to occur in the Willamette Planning Province during fiscal years 2006 and 2007. 10

Table 3.  Disturbance/disruption distances for the bald eagle during the breeding period (January 1 – August 31) and during the winter roosting period (November 15 – March 15). 14

Table 4.  Breeding and roosting periods for northern spotted owl and bald eagle. 14

Table 5. Disturbance and disruption distances for the northern spotted owl. 15

Table 6. Aggregate results of all adjusted, suitable habitat 1 acres on Northwest Forest Plan (NWFP) lands; range-wide changes by land use allocations from 1994 to January 6, 2006. 35

Table 7. Changes to suitable1 habitat acres from activities subject to section 7 consultations and other causes range-wide from 1994 to April 2004. 36

Table 8. Aggregate results of all adjusted, suitable habitat1 acres affected by section 7 consultation for the northern spotted owl; baseline and summary of effects by State, physiographic province and land use function from 1994 to April 12, 2004 (the first decade of the Northwest Forest Plan). 37

Table 9.  Change in suitable spotted owl habitat from 1994 to April 12, 2004, resulting from Federal management actions (Mgmt) and natural events by physiographic province. 38

Table 10.  Status of the northern spotted owl and its habitat within the Willamette Planning Province. 42

Table 11.  Effects of the proposed action on spotted owl habitat. 45

Table 12.  Non-habitat related effects from the proposed action and associated affects to northern spotted owls, if effects and individuals are within the disruption distances (Table 5). 47

Table 13.  Percent of land associated with disruptions around nesting spotted owl pairs when the density is: one nesting pair/4,754 acres. 49

 

LIST OF FIGURES

Figure 1.  Physiographic provinces, northern spotted owl demographic study areas, and demographic trends (Anthony et al. 2004a). 39

 


INTRODUCTION

 

This document transmits the U.S. Fish and Wildlife Service’s (Service) Biological Opinion (BO) based on our review of the Willamette Province Fiscal Year 2006 – 2007 activities described below that are proposed for implementation by the Columbia River Gorge National Scenic Area, the Mt. Hood National Forest, the Willamette National Forest, and the Salem and Eugene Districts of the Bureau of Land Management (BLM) within the Willamette Planning Province, Oregon, and their effects on the northern spotted owl (Strix occidentalis caurina) (spotted owl) and the bald eagle (Haliaeetus leucocephalus) in accordance with section 7 of the Endangered Species Act (Act) of 1973, as amended (16 U.S.C. 1531 et seq.).  Your July 29, 2005 request for formal consultation was received on August 1, 2005.

 

This Biological Opinion (BO) is based on the following major sources of information: the Forest Services’ (FS) and Bureau of Land Managements’ (BLM), July 28, 2005, Biological Assessment (BA); Forest Ecosystem Management: an Ecological, Economic, and Social Assessment (FEMAT) (Thomas and Raphael 1993); the Northwest Forest Plan (NWFP) (USDA and USDI 1994a); the Final Supplemental Environmental Impact Statement on Management of Habitat for Late-Successional and Old-Growth Forest Related Species Within the Range of the Northern Spotted Owl (USDA and USDI 1994b) (FSEIS); the Service’s BO on the NWFP (USFWS 1994); Status and Trends in Demography of Northern Spotted Owls, 1985-2003 (Anthony et al. 2004a); Scientific Evaluation of the Status of the Northern Spotted Owl (Courtney et al. 2004); our files; and informal consultation between our staff after we received your BA.

 

CONSULTATION HISTORY

 

On February 10, 1994, the Service issued the BLM and FS a non-jeopardy biological opinion (1-7-94-F-14) addressing the adoption of the Northwest Forest Plan (NWFP) and its effect on all listed species within the range of the spotted owl.  That opinion did not address any incidental take of spotted owls because the proposed action lacked sufficient details to do so.  Such analyses were deferred to future project-scale consultations where more specific information would be available on baseline (action area) conditions and project-related activities.

 

As in fiscal years 1997 - 2005, the Willamette Province Terrestrial Level 1 Team (Team) agreed to consult programmatically on activities which may affect listed species via noise, smoke and visual disturbance[1].  Since 2002, the disturbance programmatic consultations have changed from an annual process to a biennial process covering two fiscal years of activities.  This programmatic covers fiscal years 2006 and 2007 (October 1, 2005September 30, 2007).  This province-wide, programmatic approach should provide a better perspective of the cumulative impacts of numerous small projects across the Willamette Planning Province.  This effort to address impacts to listed species within the province concurrently will also more efficiently use staff time by permitting increased discussion of projects with significant impacts while they are still in the planning phase.  It is to be noted that the FS and BLM determined that the proposed activities will have no effect on spotted owl critical habitat and therefore, did not request consultation for critical habitat.

 

The Service assumes that proposed actions will comply with the Record of Decision and the Standards and Guidelines of the NWFP (USDA and USDI 1994a), and with the Willamette and Mt. Hood National Forest Land and Resource Management Plans and respective BLM Resource Management Plans, as stated in the biological assessment (BA); that is, any activity which is not wholly consistent with the NWFP, as well as the applicable Resource Management Plan, is not covered by the following biological opinion (BO).  Projects will be implemented between the signing of this BO and September 30, 2007.  No activity is covered under this BO that will adversely affect suitable habitat of any species evaluated herein.

 

For the programs of activities included in this consultation, each administrative unit estimated the number of actions, and the potential impacts of those actions, anticipated for completion in fiscal years 2006 -2007.  These estimates of potential impacts were based on currently identified projects, discussions with planners, and through assessments of projects completed in previous years.  Proposed actions will be tracked yearly using the Project Implementation and Monitoring Form (2005, disturbance only version) to monitor actions that are likely to adversely affect spotted owls.  These monitoring reports are due to the Service yearly, by December 31.

 

The Forest Service (FS) and Bureau of Land Management (BLM) prepared the Biological Assessment (BA) which was presented at the Willamette Province Terrestrial Level 1 meeting on June 15, 2005.  Final edits and team concurrence occurred at the July 14, 2005 Level 1 meeting.  After the completion of edits and signatures, the BA was received by the Fish and Wildlife Service on August 5, 2005. 

 

Formal and informal consultation was officially initiated by this office on August 5, 2005, upon receipt of the final BA signed by all five administrative units.  However, due to a request by the FS and BLM to review the more comprehensive analysis of disturbance in this BO, all parties agreed to extend the due date to March 1, 2006.  Consultation on the BA is separated into a Letter of Concurrence and this BO which addresses informal and formal consultation respectively, as per your request.  The Letter of Concurrence (1-7-05-I-0666) was issued on October 17, 2005 for concurrence on activities that had no adverse affects to any species.

 

BIOLOGICAL OPINION

 

1.0 Description of the Proposed Action

 

The BLM and the FS propose to routinely implement 16 activity types during FY 06 and 07 within the Willamette Province (see description of action area below).  A description of these activity types is presented in the BA and Tables 1 and 2 below.

 

1.1 Definitions

 

The 16 activity types were defined, in part, using the following definition of terms.

1.1.1 Spotted Owl

1.1.1.1 Suitable habitat:  Consists of stands used by owls for nesting, roosting and foraging. Generally these stands are conifer-dominated, 80 years old or older, multi-storied in structure, and have sufficient snags and down wood to provide opportunities for owl nesting, roosting and foraging. The canopy closure generally exceeds 60 percent.

 

1.1.1.2 Occupied nest location:  A known and currently active nest location.

 

1.1.1.3 Dispersal habitat:  Consists of conifer and mixed mature conifer-alder habitats with a canopy cover greater than or equal to 40 percent and conifer trees greater than or equal to 11 inches average dbh.  Generally, spotted owls use dispersal habitat to move between blocks of suitable habitat, roost, forage and survive until they can establish a nest territory.  Juvenile owls use dispersal habitat to move from natal areas.  Dispersal habitat lacks the optimal structural characteristics needed for nesting.

 

1.1.2 Bald Eagle

1.1.2.1 Suitable habitat:  Conifer-dominated habitats that generally are 80 years old or older and located within 1.0 mile of a major river or 0.5 mile of a major tributary.

 

1.1.2.2 Occupied habitat:  Suitable habitat within 0.25 mile (or 0.5 mile line-of-sight) of an active nest or roost site

 

1.1.3 Disturbance/Disruption distances

 

1.1.3.1 Disturbance distance:  Consists of the distance from the project boundary outward that would potentially cause a spotted owl if one was present to be distracted from its normal activity. 

 

1.1.3.1 Disruption distance:  Consists of the distance from the project boundary outward that would potentially cause a spotted owl, if one was present, to be distracted from its normal activity to such an extant to significantly impact its normal behavior (harass).  The disruption distance is a subset of the disturbance distance.


Table 1.  Proposed activities in the Willamette Province divided by Northwest Forest Plan Land Use Allocations.  Shaded areas indicate land allocations where the noted activity is not addressed by this biological opinion.

Activity Type

Unit of Measure*

Other Land Use Allocations

Late- Successional Reserves and Associated Riparian Reserves

Congressionally Withdrawn Areas

Aerial fertilization & seeding

Acres fertilized/ seeded

50

 

 

Aerial operations – other

Number of flights

9

5**

3

Blasting

Number of disturbance sites

31

 

 

Campground/picnic areas/ administrative sites/ trail heads – Heavy operations and maintenance

Number of disturbance sites

61

18**

0**

Firewood/ post and pole sales

Number of permits

870

 

 

Instream activities/ terrestrial habitat restoration

Number of disturbance sites

37

 

 

Invasive plant control

Number of disturbance sites

69

 

 

Miscellaneous special uses (high Intensity)

Number of disturbance sites

22

 

 

Power line maintenance

Miles of maintenance

76

37**

0**

Precommercial thinning/ stand maintenance/ riparian site preparation

Acres thinned

6,660

 

 

Prescribed burning

Acres burned

1,758

 

 

Road and dike repair

Miles of road

252

136

4

Rock quarry sites and operations

Number of disturbance sites

25

4**

0**

Salvage

Number of disturbance sites

123

33**

4**

Special forest products

Number of permits

17

 

 

Trail reconstruction, maintenance and removal

Miles of trail

157

120**

13**

*  The unit of measure for each activity type reflects the most quantifiable parameter for estimating disturbance effect.

** Needed for public safety

 

 


Table 2.  Descriptions of activities proposed to occur in the Willamette Planning Province during fiscal years 2006 and 2007.  

Proposed Activity

Description

Land Use Allocation

Aerial fertilization and seeding

The disturbance is created when fertilizer or seed is applied to past harvest areas or habitat improvement projects involving the use of aircraft. Disturbance is from repeated low-level aerial flights. The unit of measure is the number of acres treated.

Any land use allocation. Activities proposed in LSRs and congressionally withdrawn areas, shall not be scheduled during March 1 - July 15 (the NSO critical breeding period) if within the disruption distance.

Aerial operations – other

Aerial, one-time flights conducted lower than 0.25 mile (1,320 feet) above the ground that generally pass over habitat in one day but may include multiple over flights. Disturbance is from the intense noise. This also includes routine aerial law enforcement and power line inspection. The unit of measure is the number of flights.

Only high priority flights or flights required for public safety in LSRs; routine in other land use allocations.

Blasting

Includes blasting that creates noise disturbances heard no more than a mile away. This includes tree topping, debris removal, rock quarry blasting, and other activities. Disturbance is from the blasting and associated preparation activities. The unit of measure is the number of disturbance sites.

Matrix, riparian reserves, and administratively withdrawn areas ONLY.

Campgrounds/ picnic areas/ administrative sites/ trail heads – Heavy operations and maintenance

Includes infrequent activities that generate high levels of noise such as road paving, well drilling, or the replacement or construction of structures or facilities. Such operations affect listed species through disturbance from noise exceeding ambient levels resulting from the use of power equipment for heavy operations or maintenance near nesting or roosting birds. The unit of measure is the number of designated sites operated or maintained during the breeding period.

Any land use allocation. Activities proposed between March 1 and July 15 if within the disruption distance in LSRs, and congressionally withdrawn areas are included ONLY if the project is needed to protect public safety.

Firewood/post and pole sales

Firewood/post and pole sale permits include activities to which the following rules apply:

è    In LSRs and congressionally withdrawn areas, harvest of down material is allowed on landings only and shall be scheduled outside March 1 – July 15 if within the disruption distance.

è    In other land use allocations, harvest of down material may occur outside of landings within 150 feet of designated roads, if the material available for harvest is in excess of the Northwest Forest Plan (NWFP) requirements for coarse woody debris (NWFP Standards & Guides C-40).

è    Green tree alder sales along roads may occur in any land use allocation. However, activities proposed in LSRs and congressionally withdrawn areas, shall be scheduled outside of March 1 – July 15 if within the disruption distance.

The unit of measure is the number of permits issued.

See land use restrictions under Description (previous column)

Instream activities/ terrestrial habitat restoration

Instream activities include those activities constructed or created within the stream channel or immediate flood plain. They include the uses of Type I or II helicopters. Usually these activities are for fish habitat enhancements, stream channel improvement or fish passage culverts. Terrestrial habitat restoration refers to upland activities and includes tree topping (not involving blasting), snag creation, or the placement of logs for coarse woody debris habitat enhancement. The unit of measure is the number of disturbance sites.

Any land use allocation. Activities proposed in LSRs and congressionally withdrawn areas, shall not be scheduled during March 1 - July 15 if within the disruption distance.

Invasive plant control

Includes the removal of invasive plant species from a variety of habitats by methods that cause disturbances above ambient levels. Removal methods include but are not limited to hand cutting, grubbing, hand sprayers, chainsaws, cutting/mulching/ or brushing machines, and motorized sprayers. Post treatment methods include but are not limited to hand scattering of seed, planting plugs, bare root stock, mechanical seed/straw mulching machines, tractors for planting, etc. Unit of measure is disturbance site as determined by a biologist; however disturbance within an individual site may not be more than 0.5 miles apart.

Any land use allocation.

Miscellaneous special uses (high intensity)

This includes filming, black powder events, radio site access for construction activities, pile driving, concerts and stage production, rendezvous, motorcycle/off highway vehicle events, summer home maintenance, etc. No habitat modification is associated with these events. Disturbance is from noise. The unit of measure is the number of permits issued.

Any land use allocation. Activities proposed in LSRs and congressionally withdrawn areas, shall be scheduled outside March 1 - July 15 if within the disruption distance.

Power line maintenance

This activity includes:  (1) vegetation management within one tree height of the power transmission line:  and (2) structural repair of transmission line. Ground inspections are considered a necessary element of these maintenance/repair activities. The unit of measure is the number of miles maintained. (For effects from aerial inspections, see Other Aerial Operations.)

Any land use allocation. Activities proposed between March 1 and July 15 if within the disruption distance in LSRs and congressionally withdrawn areas, are included ONLY if the project is needed to protect public safety – e.g., vegetation management, or structural repair to discover, prevent, and/or fix power outages.

Precommercial thinning/ stand maintenance/ riparian site preparation

Thinning and stand maintenance is cutting down of competing vegetation in an established plantation to increase growth and survival of the remaining trees. Riparian site preparation is cutting down hardwood saplings and brush to create planting sites and/or openings so selected conifer seedlings can be planted. Disturbance is caused by use of mechanized equipment (e.g., chainsaws). The unit of measure is the number of acres treated.

Any land use allocation. Activities proposed in LSRs, and congressionally withdrawn areas shall be scheduled between July 16 and February 29.

Prescribed burning

This type of burning includes fuel reduction or habitat improvements (e.g. meadow maintenance) and restoration. Disturbance is due to smoke, mechanized equipment used in the burning process (e.g., pumps, engines, etc.). Post-harvest burning, as an activity associated with timber harvest, is covered under the Habitat Modification Biological Assessment. The unit of measure is the number of acres burned.

Matrix, riparian reserves, AMA’s and administratively withdrawn areas ONLY.

Road and dike repair

The restoration of damaged infrastructure to its previous condition, or upgrades of existing infrastructure necessary to maintain its original function or maintain public safety or to prevent anticipated damage. This also includes road decommissioning or obliteration. This activity type includes all associated actions, including the replacement of dike cores, tree removal and culvert replacement. Disturbance is from activities generally less than 7 days duration. The unit of measure is miles repaired or decommissioned (minimum unit = 0.5 mile).

Any land use allocation.

Rock quarry sites and operations

Activities include drilling, moving, crushing, and hauling of rock in a quarry site. This does not include blasting. It does not include the loss of habitat due to quarry establishment or relocation. Disturbance is from noise. The unit of measure is the number of operation sites.

Any land use allocation. Activities proposed between March 1 and July 15 if within the disruption distance in LSRs and congressionally withdrawn areas, are included ONLY if the project is needed to protect public safety.

Salvage

This activity only includes the removal of downed logs within 150 feet of the road prism and the removal of single logs from outside the road prism from matrix lands where coarse woody debris remains in excess of Northwest Forest Plan requirements (NWFP Standards & Guides C-40). In LSRs and congressionally withdrawn areas, harvest of down material shall be scheduled outside March 1 – July 15 if within the disruption distance, unless the project is needed to protect public safety. Salvage from catastrophic events (e.g, blow down) would need to be addressed separately. Disturbance is from the activities of cutting, loading, and hauling logs. The unit of measure is the number of disturbance sites.

See land use restrictions under Description.

Special forest products

Only permits for products such as burls, Christmas trees, salal, and puddle sticks where the collection (including use of small, gas-powered hand equipment), transporting, or processing within the affected forest would cause noise above ambient levels. The unit of measure is the number of disturbance sites.

Any land use allocation

Trail reconstruction, maintenance and removal

Trail reconstruction, maintenance and removal applies to activities that do not include habitat modification. This disturbance is from activities using chainsaws or other mechanical equipment producing noise that exceeds ambient levels in those areas of the forest. The unit of measure is the miles of trail improved or maintained.

Any land use allocation. Activities proposed between March 1 and July 15 if within the disruption distance in LSRs and congressionally withdrawn areas, are included ONLY if the project is needed to protect public safety.


1.2 Management Standards

 

1.2.1 General

Ø       The proposed action does not include activities that would cause the loss of bald eagle or spotted owl habitats on federal or nonfederal lands.

Ø       To ensure compliance with the standards of this assessment, and the associated concurrence letter, biological opinion and ‘incidental take’ statement, a wildlife biologist must participate in the implementation of all activities addressed by this assessment.

Ø       Prior to permitting a ‘high intensity’ miscellaneous special use (Table 2) that might affect a listed species, the administrative unit shall contact a Service representative with any questions about whether the proposed special use falls within the scope of this assessment and the associated concurrence letter, biological opinion or incidental take statement.

Ø       At the end of each calendar year, every administrative unit will complete a Project Implementation and Monitoring Form to show actual levels of adverse affects.  This form will be forwarded to the Service to fulfill monitoring report requirements.

 

1.2.2 Specific to the Bald Eagle

 

Ø      Proposed activities that would occur within the disruption distance (Table 3) of either active bald eagle nest locations during the breeding period or active bald eagle winter roosts during the winter roosting period are not addressed by this assessment.

 

1.2.3 Specific to the Spotted Owl

 

Ø       Hovering and lifting by ICS Type I or II helicopters within the disruption distance (Table 5) of occupied spotted owl nest locations or unsurveyed suitable habitat during the critical breeding period (Table 3) is not addressed by this assessment. The unit wildlife biologist may waive this seasonal restriction if the nest site or habitat is verified (by protocol) to be unoccupied.  This waiver is only applicable for the current year.

Ø       Pile driving operations would not occur within the disruption distance (Table 5) of occupied spotted owl nest locations or unsurveyed suitable habitat during the critical breeding period (Table 3).  The unit wildlife biologist may waive this seasonal restriction if the nest site or habitat is verified (by protocol) to be unoccupied.  This waiver is only applicable for the current year.

Ø       Blasting between March 1 and July 15 within the disruption distance (Table 5) of occupied spotted owl nest locations or unsurveyed suitable habitat is not addressed by this assessment.  The unit wildlife biologist may waive this seasonal restriction if the nest site or habitat is verified (by protocol) to be unoccupied.  This waiver is only applicable for the current year.

 

 

Table 3.  Disturbance/disruption distances for the bald eagle during the breeding period (January 1 – August 31) and during the winter roosting period (November 15 – March 15).


Activity (although all activities are not covered in this biological opinion, they are presented here for reference)

Potential may affect, likely to adversely affect disruption distances during the Bald Eagle Breeding period (January 1 – August 31) and winter roosting period (November 15 – March 15).

Road brushing and maintenance

440 yards (0.25 mile); 880 yards (0.5 mile) line-of-sight

Use of chainsaws

440 yards (0.25 mile); 880 yards (0.5 mile) line-of-sight

Use of heavy equipment

440 yards (0.25 mile); 880 yards (0.5 mile) line-of-sight

Burning

440 yards (0.25 mile); 880 yards (0.5 mile) line-of-sight

Use of a Type I or II helicopter1

880 yards (0.5 mile)

Use of a Type III or IV helicopter1

880 yards (0.5 mile)

Use of fixed-wing aircraft

880 yards (0.5 mile)

Use of a pile driver

440 yards (0.25 mile); 880 yards (0.5 mile) line-of-sight

Blasting

1,760 yards (1 mile)

Activity type2: Campgrounds/ picnic areas/ administrative sites/ trail heads – Normal operations and maintenance

0 yards

Activity type2: Road brushing and maintenance – well-traveled roads

0 yards

1 Incident Command System (ICS) definitions:

    Type I helicopters seat at least 16 people and have a minimum capacity of 5,000 lbs. Both a CH‑47 (Chinook) and UH‑60 (Blackhawk) are Type I helicopters.

    Type II helicopters seat at least 10 people and have a minimum capacity of 2,500 lbs. Both a Bell UH1‑H and a Bell 212 are Type II helicopters.

    Type III helicopters seat at least 5 people and have a minimum capacity of 1,200 lbs. Both a Bell 206 and a Hughes 500 are Type III helicopters.

    Type IV helicopters seat at least 3 people and have a minimum capacity of 600 lbs

2   These activity types as are not restricted due to the lower intensities of these activities with respect to ambient noise and human activity levels within the action area.

 

Table 4.  Breeding and roosting periods for northern spotted owl and bald eagle.

 

Breeding Period

Critical Breeding Period

Winter Roosting Period

Northern spotted owl

March 1 – September 30

March 1 – July 15

 

Bald eagle

January 1 – August 31

January 1 – August 31

November 15 – March 15


Table 5. Disturbance and disruption distances for the northern spotted owl.


Activity (although all activities are not covered in this biological opinion, they are presented here for reference)

Potential may affect disturbance distances during the spotted owl breeding period (March 1 – September 30)

Potential may affect, likely to adversely affect disruption distances during the spotted owl critical breeding period (March 1 – July 15)

Potential may affect, likely to adversely affect disruption distances during the remainder of the spotted owl breeding period (July 16 – September 30)

Use of chainsaws

440 yards (0.25 mile)

65 yards

0 yards

Use of heavy equipment

440 yards (0.25 mile)

35 yards

0 yards

Burning

440 yards (0.25 mile)

440 yards (0.25 mile)

0 yards

Type I or II helicopter1

880 yards (0.5 mile)

440 yards (0.25 mile)

440 yards (0.25 mile)

Type III or IV helicopter1

440 yards (0.25 mile)

120 yards

0 yards

Use of fixed-wing aircraft

440 yards (0.25 mile)

120 yards

0 yards

Use of a pile driver

440 yards (0.25 mile)

60 yards

0 yards

Blasting

1,760 yards (1 mile)

1,760 yards (1 mile)

440 yards (0.25 mile)

Rock crushing

440 yards (0.25 mile)

180 yards

0 yards

1 Incident Command System (ICS) definitions:

    Type I helicopters seat at least 16 people and have a minimum capacity of 5,000 lbs. Both a CH‑47 (Chinook) and UH‑60 (Blackhawk) are Type I helicopters.

    Type II helicopters seat at least 10 people and have a minimum capacity of 2,500 lbs. Both a Bell UH1‑H and a Bell 212 are Type II helicopters.

    Type III helicopters seat at least 5 people and have a minimum capacity of 1,200 lbs. Both a Bell 206 and a Hughes 500 are Type III helicopters.

    Type IV helicopters seat at least 3 people and have a minimum capacity of 600 lbs.

 

1.3 Action Area

 

The action area is defined (50 CFR 402) as, “all areas to be affected directly or indirectly by the Federal action and not merely the immediate area involved in the action.”  The action area for the proposed actions includes all lands managed by the FS and BLM within the Willamette Planning Province, and associated lands within one mile.

 

The Willamette Planning Province consists of lands associated within the Oregon Western Cascades Physiographic Province[2] that are administered by the Eugene and Salem districts of the BLM, the Mt. Hood National Forest, the Willamette National Forest and the Columbia River Gorge National Scenic Area (CRGNSA) and lands administered by the Mt. Hood National Forest, Willamette National Forest and CRGNSA associated with the Oregon Eastern Cascades Physiographic Province.

 

2.0 Status of the NORTHERN SPOTTED OWL

 

2.1 Legal Status

 

The spotted owl was listed as threatened on June 26, 1990.  It was listed due to widespread habitat loss across the entirety of its range and the inadequacy of existing regulatory mechanisms to provide for its conservation (USFWS 1990b).

 

2.2 Life History

 

2.2.1 Taxonomy

The spotted owl is one of three subspecies of spotted owls currently recognized by the American Ornithologists’ Union and is typically associated with old-growth forested habitats throughout the Pacific Northwest.  The taxonomic separation of these three subspecies is supported by genetic (Barrowclough and Gutiérrez 1990), morphological (Gutiérrez et al. 1995) and biogeographic information (Barrowclough and Gutiérrez 1990).  More detailed accounts of the taxonomy, ecology, and reproductive characteristics of the spotted owl are found in the 1987 and 1990 U.S. Fish and Wildlife Service Status Reviews (USFWS 1987, 1990a), the 1989 Status Review Supplement (USFWS 1989), the Interagency Scientific Committee (ISC) Report (Thomas et al. 1990), the Forest Ecosystem Management Assessment Team (FEMAT) Report (Thomas and Raphael 1993), final rule designating the spotted owl as a threatened species (USFWS 1990b), and Scientific Evaluation of the Status of the Northern Spotted Owl (Courtney et al. 2004). 

 

2.2.2 Physical Description

The spotted owl is a medium-sized owl, about 46-48 cm in length and weighing approximately 490-850 g (Gutiérrez et al. 1995).  It is the largest of the three subspecies (Gutiérrez et al. 1995).  The spotted owl is dark brown with a barred tail and white spots on the head and breast, and it has dark brown eyes that are surrounded by prominent facial disks.  Three age classes can be distinguished on the basis of plumage characteristics (Forsman 1981, Moen et al. 1991).  The spotted owl superficially resembles the barred owl (Strix varia), a species with which it occasionally hybridizes (Kelly et al. 2003).  Hybrids exhibit characteristics of both species (Hamer et al. 1994).                  

 

2.2.3 Current and Historical Range 

The current range and distribution of the spotted owl extends from southern British Columbia through western Washington, Oregon, and California, as far south as Marin County (USFWS 1990a).  The southeastern boundary of its range is the Pit River area of Shasta County, California.  The range of the spotted owl is partitioned into 12 physiographic provinces (provinces), based on recognized landscape subdivisions exhibiting different physical and environmental features (Thomas et al. 1993).  These provinces are distributed across the range as follows: 4 provinces in Washington (Washington Cascades East, Olympic Peninsula, Washington Cascades West, Western Lowlands); 5 provinces in Oregon (Oregon Coast Range, Willamette Valley, Oregon Cascades West, Oregon Cascades East, Klamath Mountains); and 3 provinces in California (California Coast, California Klamath, California Cascades).  Although the current range of the spotted owl is similar to its historical range where forested habitat still exists (the distribution is relatively contiguous, but influenced by the natural insularity of habitat patches within geographic province, and by natural and man-caused fragmentation of vegetation), the spotted owl is extirpated or uncommon in certain areas (e.g., southwestern Washington).  Timber harvest activities have eliminated, reduced or fragmented spotted owl habitat sufficiently to decrease overall population densities across its range, particularly within the coastal provinces where habitat reduction has been concentrated (Thomas and Raphael 1993).

 

2.2.4 Behavior

Spotted owls are territorial.  However, the fact that home ranges of adjacent pairs overlap (Forsman et al. 1984, Solis and Gutiérrez 1990) suggests that the area defended is smaller than the areas used for foraging.  Territorial defense is primarily effected by hooting, barking and whistle type calls. 

 

Spotted owls are monogamous and usually form long-term pair bonds.  “Divorces” occur but are relatively uncommon.  There are no known examples of polygyny in this owl, although associations of three or more birds have been reported (Gutiérrez et al. 1995).

 

2.2.5 Habitat Relationships

2.2.5.1 Home Range.  Spotted owl home range size varies by province.  Home range generally increases from south to north, which is likely in response to decreasing habitat quality (USFWS 1990a).  Home range size was linked to habitat type, availability, and abundance of prey (Zabel et al. 1995).

 

Based on available radio-telemetry data (Thomas et al. 1990), the Service estimated median annual home range size for the spotted owl by province throughout the range of the spotted owl.  Because the actual configuration of the home range is rarely known, the estimated home range of a spotted owl pair is represented by a circle centered upon a spotted owl activity center, with an area approximating the provincial median annual home range.  For example, estimated home range area varies from 3,340 acres (based on a 1.3-mile radius area) in California to 14,271 acres (based on a 2.7-mile radius circle) in Washington.  The Service uses a 0.7-mile radius circle (984 acres) to delineate the area most heavily used (core area) by spotted owls during the nesting season.  Spotted owls in northern California focused their activities in core areas that ranged from about 167 to 454 acres, with a mean of about 409 acres; about half the area of the 0.7-mile radius circle (Bingham and Noon 1997).  Spotted owls maintain smaller home ranges during the breeding season and often dramatically increase their home range size during fall and winter (Forsman et al. 1984, Sisco 1990). 

 

Although differences exist in natural stand characteristics that influence provincial home range size, habitat loss and forest fragmentation caused by timber harvest effectively reduce habitat quality in the home range.  A reduction in the amount of suitable habitat reduces spotted owl abundance and nesting success (Bart and Forsman 1992, Bart 1995).

 

2.2.5.2 Habitat Use.  Forsman et al. (1984) report that spotted owls have been observed in the following forest types: Douglas-fir (Pseudotsuga menziesii), western hemlock (Tsuga heterophylla), grand fir (Abies grandis), white fir (Abies concolor), ponderosa pine (Pinus ponderosa), Shasta red fir (Abies magnifica shastensis), mixed evergreen, mixed conifer hardwood (Klamath montane) and redwood (Sequoia sempervirens).  Use of these types coincides with appropriate forest structure (see below).  In parts of the Oregon Coast Range, spotted owls have been recorded in pure hardwood stands.  In California, spotted owls are found from near sea level in coastal forests to approximately 2130 m in the Cascades (Gutiérrez 1996).  The upper elevation limits at which spotted owls occur, decrease gradually with increasing latitude in Oregon and Washington.  In all areas, the upper elevation limit at which spotted owls occur correspond to the transition to subalpine forest, which is characterized by relatively simple structure and sever winter weather (Gutiérrez 1996).

 

Roost sites selected by spotted owls have more complex vegetation structure than forests generally available to them (Barrows and Barrows 1978, Forsman et al. 1984, Solis and Gutiérrez 1990).  These habitats are usually multi-layered forests having high canopy closure and large diameter trees in the overstory. 

 

Spotted owls nest almost exclusively in trees.  Like roosts, nest sites are found in forests having complex structure dominated by large diameter trees (Forsman et al. 1984, Hershey et al. 1998).  Even in forests that have been previously logged, spotted owls select forests having a structure (i.e., larger trees, greater canopy closure) different than forests generally available to them (Folliard 1993, Buchanan et al. 1995, Hershey et al. 1998).

 

Foraging habitat is the most variable of all habitats used by territorial spotted owls (Thomas et al. 1990).  Descriptions of foraging habitat have ranged from complex structure (Solis and Gutiérrez 1990) to forests with lower canopy closure and smaller trees than forests containing nests or roosts (Gutiérrez 1996).

 

2.2.5.3 Habitat Selection.  Spotted owls generally rely on older forested habitats because they contain the structures and characteristics required for nesting, roosting, foraging, and dispersal.  These characteristics of older forests include the following: a multi-layered, multi-species canopy dominated by large overstory trees; moderate to high canopy closure; a high incidence of trees with large cavities and other types of deformities; numerous large snags; an abundance of large, dead wood on the ground; and open space within and below the upper canopy for spotted owls to fly (Thomas et al. 1990, USFWS 1990a).  Forested stands with high canopy closure also provide thermal cover (Weathers et al. 2001), as well as protection from predation.  Recent landscape-level analyses suggest that a mosaic of late-successional habitat interspersed with other vegetation types may benefit spotted owls more than large, homogeneous expanses of older forests (Meyer et al. 1998, Franklin et al. 2000, Zabel et al. 2003).  In redwood forests along the coast range of California, spotted owls may be found in younger forest stands with structural characteristics of older forests (Thomas et al. 1990).  However, spotted owls do not generally appear to select for stands of intermediate or younger ages (Solis and Gutiérrez 1990).

 

In mixed conifer forests of the Eastern Cascades, Washington, 27 percent of nest sites were in old-growth forests, 57 percent in the understory reinitiation phase of stand development, and 17 percent in the stem exclusion phase (Buchanan et al. 1995).  In the Western Cascades, Oregon, 50 percent of spotted owl nests were in late-seral/old-growth stands (> 80-yrs-old) and none were found in stands less than 40-yrs-old (Irwin et al. 2000).

 

Ward (1990) found spotted owls foraged in areas that had lower variance in prey densities (prey were more predictable in occurrence) within older forests and near ecotones of old forest and brush seral stages.  Zabel et al. (1995) showed that spotted owl home ranges are larger where flying squirrels (Glaucomys sabrinus) are the predominant prey and, conversely, are smaller where woodrats (Neotoma spp.) are the predominant prey.

 

In the Western Washington Cascades, spotted owls used mature/old forests dominated by trees greater than 50 cm diameter-at-breast height (dbh) with greater than 60 percent canopy closure more often than expected for roosting during the non-breeding season and used young forest (trees 20-50 cm dbh with > 60 percent canopy closure) less often than expected based on availability (Herter et al. 2002).

 

2.2.6 Reproductive Biology

Spotted owls exhibit high adult annual survival rates and are relatively long-lived (USFWS 1992a).  Spotted owls do not typically reach sexual maturity until after 2 years (Thomas et al. 1990).  Once an adult, females lay an average of 2 eggs per clutch (range 1-4 eggs), although specific spotted owl pairs do not typically nest every year, nor are nesting pairs successful every year (USFWS 1990a).  The small clutch size, temporal variability in nesting success, and somewhat delayed maturation all contribute to the relatively low fecundity of this species (Gutiérrez 1996).

 

Nest sites are usually located within stands of old-growth and late-successional forest dominated by Douglas-fir (Pseudotsuga menziesii), and they contain structures such as cavities, broken tree tops, or mistletoe (Arceuthobium spp.) brooms (Forsman et al. 1984, Blakesley et al. 1992, LaHaye and Gutiérrez 1999).  In general, courtship and nesting behavior begins in February to March with nesting occurring from March to June; however, timing of nesting and fledging varies with latitude and elevation (Forsman et al. 1984).  After young fledge from the nest, they depend on their parents until they are able to fly and hunt on their own.  Parental care continues post-fledging into September (USFWS 1990b), and sometimes into October (Forsman et al. 1984).  During this time the adults may not roost with their young during the day, but they respond to begging vocalizations by bringing food to the young (Forsman et al. 1984).

 

Some spotted owls are not territorial, they either remain as residents within the territory of a pair or move among territories (Gutiérrez 1996), and these birds are referred to as floaters.  Floaters have special significance in spotted owl populations because they may buffer the territorial population from decline (Franklin 1992).  Little is known about floaters other than that they exist and typically do not respond to calls as vigorously as territorial birds (Gutiérrez 1996).

 

2.2.7 Dispersal Biology

Natal dispersal of spotted owls from Oregon and Washington typically begins from mid- to late-September, and it is remarkably synchronous across broad areas (Forsman et al. 2002).  When data from many dispersing spotted owls are pooled, the direction of dispersal away from the natal site appears random (Miller 1989, Ganey et al. 1998, Forsman et al. 2002).  Dispersal direction from individual territories, however, may be non-random in response to the local distribution of habitat and topography (Forsman et al. 2002).  Natal dispersal occurs in stages, with juvenile spotted owls settling in temporary home ranges between bouts of dispersal (Forsman et al. 2002).  Median natal dispersal distance is about 10 miles for males and 15.5 miles for females (Forsman et al. 2002, see also Miller 1989, Ganey et al. 1998).  Successful dispersal of juvenile spotted owls may depend on their ability to locate unoccupied suitable habitat in close proximity to other occupied sites (Lahaye et al. 2001). 

 

Breeding dispersal occurs among a small proportion of adult spotted owls; these movements were more frequent among females and unmated individuals (Forsman et al. 2002).  Breeding dispersal distances were shorter than natal dispersal distances and also are apparently random in direction (Forsman et al. 2002).

 

Large non-forested valleys are apparent barriers to natal and breeding dispersal; forested foothills between valleys providing the only opportunities for dispersal (Forsman et al. 2002).  The degree to which water bodies, such as the Columbia River and Puget Sound, function as barriers to dispersal is unclear.  Analysis of genetic structure of spotted owl populations suggests adequate rates of gene flow may occur between the Olympic Mountains and Washington Cascades (across the Puget Trough) and between the Olympic Mountains and the Coast Range of Oregon (across the Columbia River) (Haig et al. 2001).  Both telemetry and genetic studies indicate inbreeding is rare.

 

Dispersing juvenile spotted owls experience high mortality rates, exceeding 70 percent in some studies (Miller 1989, USFWS 1990b).  Leading known causes of mortality are starvation, predation, and accidents (Miller 1989, USFWS 1990b, Forsman et al. 2002).  Parasitic infection may contribute to these causes of mortality (Forsman et al. 2002).  In a study on habitat use by dispersing juvenile spotted owls in the Oregon Coast Range, Klamath and Western Oregon Cascades Provinces (Miller et al. 1997), mature and old-growth forest were used slightly more than expected based on availability during the transient phase and nearly twice its availability during the colonization phase.  Closed pole-sapling-sawtimber habitat was used roughly in proportion to availability in both phases; open sapling and clearcuts were used less than expected based on availability during colonization.

 

2.2.8 Food Habits 

Spotted owls are mostly nocturnal (Forsman et al. 1984), but they may forage opportunistically during the day (Laymon 1991, Sovern et al. 1994).  Composition of prey in the spotted owl’s diet varies regionally, seasonally, annually, and locally, which is likely in response to prey availability (Laymon 1988, Duncan and Sidner 1990, Ganey 1992, Verner et al. 1992, Carey 1993, Ward and Block 1995, Forsman et al. 2001).  Northern flying squirrels and woodrats are usually the predominant prey both in biomass and frequency (Barrows 1980; Forsman et al. 1984; Ward 1990; Bevis et al. 1997; Forsman et al. 2001, 2004) with a clear geographic pattern of diet, paralleling differences in habitat (Thomas et al. 1990).  Northern flying squirrels are generally the dominant prey item in the more mesic Douglas-fir/western hemlock forests characteristic of the northern portion of the range, whereas woodrats are generally the dominant prey item in the drier mixed conifer/mixed evergreen forests typically found in the southern portion of the range (Forsman et al. 1984, Thomas et al. 1990, Ward et al. 1998, reviewed by Courtney et al. 2004).  These prey items were found to be co-dominant in the southwest interior of Oregon (Forsman et al. 2001, 2004). 

 

Other prey species (i.e., red tree vole [Arborimus longicaudas], red backed voles [Clethrionomys gapperi], mice, rabbits and hares, birds, and insects) may be seasonally or locally important (reviewed by Courtney et al. 2004).  For example, Rosenberg et al. (2003) showed a strong correlation between annual reproductive success of spotted owls (number of young per territory) and abundance of deer mice (Peromyscus maniculatus) (r2 = 0.68), despite the fact they only made up 1.6±0.5 percent of the biomass consumed.  However, it is unclear if the causative factor behind this correlation was prey abundance or a synergistic response to weather (Rosenberg et al. 2003).  Nonetheless, spotted owls deliver larger prey to the nest and eat smaller food items to reduce foraging energy costs; therefore, the importance of smaller prey items, like Peromyscus, in the spotted owl diet should not be underestimated (Forsman et al. 1984, 2001, 2004).  

 

2.2.9 Population Dynamics

The spotted owl is a relatively long-lived organism; produces few, but large young; invests significantly in parental care; experiences later or delayed maturity; and exhibits high adult survivorship.  The spotted owl’s long reproductive life span allows for some eventual recruitment of offspring, even if recruitment does not occur each year (Franklin et al. 2000). 

 

Annual variation in population parameters for spotted owls has been linked to environmental influences at various life history stages (Franklin et al. 2000).  In coniferous forests, mean fledgling production of the California spotted owl (Strix occidentalis occidentalis), another closely related subspecies, was higher when minimum spring temperatures were higher (North et al. 2000), a relationship that may be a function of increased prey availability.  Across their range, spotted owls have previously shown a pattern of alternating years of high and low reproduction, with highest reproduction occurring during even-numbered years (e.g., Franklin et al. 1999).  Annual variation in breeding may be related to weather conditions and fluctuation in prey abundance (Zabel et al. 1995).

 

A variety of factors may regulate spotted owl population levels.  These factors may be density-dependent (e.g., habitat quality, habitat abundance) or density-independent (e.g., climate).  Interactions may occur among factors.  For example, as habitat quality decreases, density-independent factors may have more influence on variation in rate of population growth, which tends to increase variation in the rate of growth (Franklin et al. 2000).  A consequence of this pattern is that at some point, lower habitat quality may cause the population to be unregulated and decline to extinction (Franklin et al. 2000).

 

2.3 Threats

 

2.3.1 Reasons for Listing

The spotted owl was listed as threatened throughout its range “due to loss and adverse modification of suitable habitat as a result of timber harvesting and exacerbated by catastrophic events such as fire, volcanic eruption, and wind storms” (USFWS 1990a).  More specifically, significant threats to the spotted owl included the following: low populations, declining populations, limited habitat, declining habitat, distribution of habitat or populations, isolation of provinces, predation and competition, lack of coordinated conservation measures, and vulnerability to natural disturbance (USFWS 1992a).  These threats were characterized for each province as severe, moderate, low, or unknown.  Declining habitat was recognized as a severe or moderate threat to the spotted owl in all 12 provinces, isolation of provinces within 11 provinces, and declining populations in 10 provinces.  Consequently, these three factors represented the greatest concern range-wide to the conservation of the spotted owl.  Limited habitat was considered a severe or moderate threat in nine provinces, and low populations a severe or moderate concern in eight provinces, suggesting that these factors are a concern throughout the majority of the range.  Vulnerability to natural disturbances was rated as low in five provinces. 

 

The degree to which predation and competition might pose a threat to the spotted owl was unknown in more provinces than any of the other threats, indicating a need for additional information.  Few empirical studies exist to confirm that habitat fragmentation contributes to increased levels of predation on spotted owls.  However, great horned owls (Bubo virginianus), an effective predator on spotted owls, are closely associated with fragmented forests, openings, and clearcuts (Johnson 1992, Laidig and Dobkin 1995).  As mature forests are harvested, great horned owls may colonize fragmented forests, thereby increasing spotted owl vulnerability to predation.

 

2.3.2 New Threats

2.3.2.1 Barred Owls.  Since the listing of the spotted owl under the Act, new information suggests that hybridization with the barred owl is less of a threat (Kelly and Forsman 2004) and competition with the barred owl is a greater threat than previously anticipated (Courtney et al. 2004).  Since 1990, the barred owl has expanded its range south into Marin County, California and the central Sierra Nevada Mountains, such that it is now roughly coincident with the range of the spotted owl (Courtney et al. 2004).  Further, notwithstanding the likely bias in survey methods towards underestimating actual barred owl numbers (Courtney et al. 2004), barred owl populations appear to be increasing throughout the Pacific Northwest, particularly in Washington and Oregon (Zabel et al. 1996, Dark et al. 1998, Wiedemeier and Horton 2000, Kelly et al. 2003, Pearson and Livezey 2003, Anthony et al. 2004a).  

 

Barred owl numbers now may exceed spotted owl numbers in the northern Washington Cascades (Kuntz and Christopherson 1996) and British Columbia (Dunbar et al. 1991) and appear to be approaching spotted owl numbers in several other areas (e.g., Redwood National and State Parks in California [Schmidt 2003]).  Barred owl populations in the Pacific Northwest appear to be self-sustaining based on current density estimates and apparent distribution (Courtney et al. 2004).

 

Barred owls apparently compete with spotted owls through a variety of mechanisms: prey overlap (Hamer et al. 2001), habitat overlap (Hamer et al. 1989, Dunbar et al. 1991, Herter and Hicks 2000, Pearson and Livezey 2003), and agonistic encounters (Leskiw and Gutiérrez 1998, Pearson and Livezey 2003).  New information on encounters between barred owls and spotted owls comes primarily from anecdotal reports which corroborate initial observations that barred owls react more aggressively towards spotted owls than the reverse (Courtney et al. 2004).  There is also limited circumstantial evidence of barred owl predation on spotted owls (Leskiw and Gutiérrez 1998, Johnston 2002).  Information collected to date indicates that encounters between these two species tend to be agonistic in nature, and that the outcome is unlikely to favor the spotted owl (Courtney et al. 2004).  

 

Although barred owls were initially thought to be more closely associated with early successional forests than spotted owls (Hamer 1988, Iverson 1993), recent studies indicate that barred owls are capable of utilizing a broader range of habitat types relative to spotted owls (Courtney et al. 2004).  The only study comparing spotted owl and barred owl food habits in the Pacific Northwest indicated that barred owl diets overlapped strongly (>75 percent) with spotted owl diets (Hamer et al. 2001).  However, barred owl diets were also more diverse than spotted owl diets, including species associated with riparian and other moist habitats, as well more terrestrial and diurnal species.

 

Evidence that barred owls are causing the displacement of spotted owls is largely indirect, based primarily on retrospective examination of long-term data collected on spotted owls.  Correlations between local spotted owl declines and barred owl increases have been noted in the northern Washington Cascades (Kuntz and Christopherson 1996, Herter and Hicks 2000, Pearson and Livezey 2003), on the Olympic peninsula (Wiedemeier and Horton 2000; Gremel 2000, 2003), in the southern Oregon Cascades (e.g., Crater Lake National Park [Johnston 2002]), and in the coastal redwood zone in California (e.g., Redwood National and State Parks [Schmidt 2003]). 

 

Spotted owl occupancy was significantly lower in spotted owl territories where barred owls were detected within 0.8 km (0.5 mi) of the spotted owl territory center than in spotted owl territories where no barred owls were detected (Kelly et al. 2003).  Kelly et al. (2003) also found that in spotted owl territories where barred owls were detected, spotted owl occupancy was significantly lower (P < 0.001) after barred owls were detected within 0.8 km of the territory center; occupancy was “only marginally lower” (P = 0.06) if barred owls were located more than 0.8 km from spotted owl territory centers.  In a Roseburg, Oregon study area, 46 percent of spotted owls moved more than 0.8 km, and 39 percent of spotted owls were not relocated again in at least 2 years after barred owls were detected within 0.8 km of the territory center.  Observations provided by Gremel (2000) from the Olympic National Park are consistent with those of Kelly et al. (2003); he documented significant displacement of spotted owls following barred owl detections “coupled with elevational changes of spotted owl sites on the east side of the Park” (Courtney et al. 2004).  Pearson and Livezey (2003) reported similar findings on the Gifford Pinchot National Forest where unoccupied spotted owl sites were characterized by significantly more barred owl sites within 0.8‑km, 1.6‑km, and 2.9‑km from the territory center than in occupied spotted owl sites.

 

At two study areas in Washington, investigators found relatively high numbers of territories previously occupied by spotted owls that are now apparently not occupied by either spotted or barred owls (e.g., 49 of 107 territories in the Cascades [Herter and Hicks 2000]; 23 of 33 territories in the Olympic Experimental State Forest [Wiedemeier and Horton 2000]).  Given that habitat was still present in these vacant territories, some factor(s) may be reducing habitat suitability or local abundance of both species.  For example, weather conditions could cause prolonged declines in abundance of both species (Franklin et al. 2000).  Because spotted owls have been anecdotally reported to give fewer vocalizations when barred owls are present, it is possible that these supposed vacant territories are still occupied by spotted owls that do not respond to surveys.  Likewise, survey protocols for spotted owls are believed to under-detect barred owls (Courtney et al. 2004).  Thus, some proportion of seemingly vacant territories may be an artifact of reduced detection probability of the survey protocol.  Nonetheless, previously occupied territories apparently vacant of both Strix species suggests that factors other than barred owls alone are contributing to declines in spotted owl abundance and territorial occupancy (Courtney et al. 2004).

 

Two studies (Kelly 2001, Anthony et al. 2004a) attempted to determine whether barred owls affected fecundity of spotted owls in the long-term demographic study areas.  Neither study was able to clearly do so, although the Wenatchee and Olympic demographic study areas showed possible effects (Anthony et al. 2004a).  However, both studies described the shortfalls of their methods to adequately test for this effect.  Iverson (2004) reported no effect of barred owl presence on spotted owl reproduction, but his results could have been influenced by small sample size (Livezey, in review).  Barred owls had a negative effect on spotted owl survival on the Wenatchee and Olympic study areas and possibly an effect on the Cle Elum study area (Anthony et al. 2004a).  Olson et al. 2004 found a significant (but weak) negative effect of barred owl presence on spotted owl reproductive output but not on survival at a Roseburg, Oregon study area (Courtney et al. 2004).

 

Regarding interactions between barred and spotted owls, the uncertainties associated with methods, analyses, and possible confounding factors (e.g., effects of past habitat loss, weather) warrant caution in interpretation of the patterns emerging from the data and information collected to date (Courtney et al. 2004).  Further, data are currently lacking that would allow accurate prediction of how barred owls will affect spotted owls in the southern, more xeric, portion of the range (i.e., California and Oregon Klamath regions).  In spite of these uncertainties, the preponderance of the evidence gathered thus far is consistent with the hypothesis that barred owls are playing some role in spotted owl population decline, particularly in Washington and portions of Oregon and the northern coast of California (Courtney et al. 2004).

 

Courtney et al. (2004) compared the size differences between barred owls and spotted owls in the Pacific Northwest to size ratios of coexisting Strix owl species, including that of the Mexican spotted owl (Strix occidentalis lucida) and the barred owl in the southwest U.S. and Mexico.  This analysis was conducted to explore the potential for eventual coexistence of, or niche partitioning by, barred owls and spotted owls based primarily on differences in size.  Results of this analysis indicated that the difference in size between the spotted owl and barred owl in the Pacific Northwest was only 17.5 percent, lower than ratios calculated for all other assemblages examined.  The SEI panel concluded that this difference may be too slight to permit “coexistence by dint of size and size-related ecology alone” (Courtney et al. 2004).

 

Although the barred owl currently constitutes a significantly greater threat to the spotted owl than originally thought at the time of listing (Courtney et al. 2004) at present, it is unclear whether forest management has an effect on the outcome of interactions between barred and spotted owls (Courtney et al. 2004, summarized by Lint 2005).  The most recent summaries compiled on the barred owl (Courtney et al. 2004, Lint 2005, USFWS 2004) do not provide recommendations on how to deal with this potential threat.  The USFWS (USFWS 2004) did not consider the increased risk to spotted owl populations due to the uncertainties surrounding barred owls and other factors sufficient to reclassify the subspecies as endangered at this time.  Because it was not clear if additional protection of spotted owl habitat would reverse the population trends in some portions of the species’ range, and because the results of their study did not identify the causes of those trends, Anthony et al. (2004) declined to make any recommendations to alter the current NWFP management strategy.

 

2.3.2.2 Wildfire. At the time of listing there was recognition that catastrophic wildfire posed a threat to the spotted owl (USFWS 1990a).  New information suggests fire may be more of a threat than previously thought.  In particular, the rate of habitat loss in the relatively dry East Cascades and Klamath provinces has been greater than expected (see “Habitat Trends” below).  However, the total amount of habitat affected by wildfires has been relatively small (Lint 2005).  We may be able to influence, through silvicultural management, how fire prone forests will burn and the extent of the fire when the inevitable occurs.  Such silvicultural efforts are currently being implemented throughout the spotted owl’s range, in an attempt to overcome nearly 100 years of effective fire suppression.  However, we now recognize that our ability to protect spotted owl habitat and viable populations of spotted owls from these large fires through risk-reduction endeavors is largely uncertain (Courtney et al. 2004).  Lint (2005) indicated that the NWFP recognized wildfire as an inherent part of managing spotted owl habitat in certain portions of the range.  The repetitive design of the NWFP can help mitigate the risks associated with large-scale fire (Lint 2005).

 

In 1994, the Hatchery Complex wildfires burned 17,603 ha in the Wenatchee National Forest, eastern Cascades, Washington, affecting six spotted owl activity centers (Gaines et al. 1997).  Spotted owl habitat within a 2.9 km radii of the activity centers was reduced by 8 to 45 percent (mean = 31 percent) due to direct effects of the fire and by 10 to 85 percent (mean = 55 percent) due to delayed mortality of fire-damaged trees and insect caused tree mortality.  Spotted owl habitat loss was greater on mid to upper slopes (especially south-facing) than within riparian areas or on benches (Gaines et al. 1997).  Direct mortality of spotted owls was assumed to have occurred at one site.  Data were too sparse for reliable comparisons of site occupancy or reproductive output between sites affected by the fires and other sites on the Wenatchee National Forest.  

 

Two wildfires burned in the Yakama Indian Reservation, eastern Cascades, Washington, in 1994, affecting home ranges of two radio-tagged spotted owls (King et al. 1997).  Although the amount of home ranges burned was not quantified, spotted owls were observed using areas that received low and medium intensity burning.  No direct mortality of spotted owls was observed even though thick smoke covered several spotted owl site centers for a week. 

 

2.3.2.3 West Nile Virus.  West Nile virus (WNV) has been identified as a potential threat of unknown magnitude to the spotted owl (Courtney et al. 2004), and has the potential to reduce the population numbers beyond the projected decline anticipated under the NWFP (Lint 2005).  Thus far, no mortality in wild spotted owls has been recorded.  Habitat restoration for spotted owls will likely take decades to be realized.  As such, it is too early to evaluate the long-term effectiveness of conservation efforts and regulatory changes in conserving spotted owls.  However, the WNV threat to the spotted owl may not respond to or be affected by habitat management or improvement (USFWS 2004).

 

WNV has killed millions of wild birds in North America since it arrived in 1999 (McLean et al. 2001, Caffrey 2003, Marra et al. 2004).  Mosquitoes are the primary carriers (vectors) of the virus that causes encephalitis in humans, horses, and birds.  Mammalian prey may also play a role in spreading WNV among predators, like spotted owls.  Owls and other predators of mice can contract the disease by eating infected prey (Garmendia et al. 2000, Komar et al. 2001).  Recent tests of tree squirrels (which includes flying squirrels) from Los Angeles County, California, found over 70 percent were positive for WNV (R. Carney, pers. comm. 2004, cited in Courtney et al. 2004).  One captive spotted owl in Ontario, Canada, is known to have contracted WNV and died.

 

Health officials expect that WNV will eventually spread throughout the range of the spotted owl (Courtney et al. 2004), but it is unknown how WNV will ultimately affect spotted owl populations.  Susceptibility to infection and mortality rates of infected individuals vary among bird species, even within groups (Courtney et al. 2004).  Owls appear to be quite susceptible.  For example, breeding screech owls (Megascops asio) in Ohio experienced 100 percent mortality (T. Grubb, pers. comm., cited in Courtney et al. 2004).  Barred owls, in contrast, showed lower susceptibility (B. Hunter, pers. comm., cited in Courtney et al. 2004).  Some level of innate resistance may occur (Fitzgerald et al. 2003), which could explain observations in several species of markedly lower mortality in the second year of exposure to WNV (Caffrey and Peterson 2003).  Wild birds also develop resistance to WNV through immune responses (Deubel et al. 2001).  The effects of WNV on bird populations at a regional scale have not been large, even for susceptible species (Caffrey and Peterson 2003), perhaps due to the short-term and patchy distribution of mortality (K. McGowan, pers. comm., cited in Courtney et al. 2004) or annual changes in vector abundance and distribution.

 

Courtney et al. (2004) offer competing propositions for the likely outcome of spotted owl populations being infected by WNV.  One proposition is that spotted owls can tolerate severe, short-term population reductions due to WNV, because spotted owl populations are widely distributed and number in the several hundreds to thousands.  An alternative proposition is that WNV will cause unsustainable mortality, due to the frequency and/or magnitude of infection, thereby resulting in long-term population declines and extirpation from parts of the spotted owl’s current range. 

 

2.3.2.4 Sudden Oak Death.  Sudden oak death was recently identified as a potential threat to the spotted owl (Courtney et al. 2004).  This disease is caused by the fungus-like pathogen, Phytopthora ramorum that was recently introduced from Europe and is rapidly spreading.  At the present time, sudden oak death is found in natural stands from Monterey to Humboldt Counties, California, and has reached epidemic proportions in oak (Quercus spp.) and tanoak (Lithocarpus densiflorus) forests along about 300 km of the central and northern California coast (Rizzo et al. 2002).  It has also been found near Brookings, Oregon, killing tanoak and causing dieback of closely associated wild rhododendron (Rhododendron spp.) and evergreen huckleberry (Vaccinium ovatum) (Goheen et al. 2002).  It has been found in several different forest types and at elevations from sea level to over 800 m.  It poses a threat of uncertain proportion because of its potential impact on forest dynamics and alteration of key habitat components (i.e., hardwood trees); especially in the southern portion of the spotted owl’s range (Courtney et al. 2004).  However, the potential for management to address the additive effects of sudden oak death on habitat availability is unknown and substantial uncertainty about its effects mediated against placing too much weight on this factor in the USFWS Five-Year Review Evaluation (USFWS 2004).

 

2.3.2.5 Inbreeding Depression, Genetic Isolation, and Reduced Genetic Diversity.  Inbreeding and other genetic problems due to small population sizes were not considered an imminent threat to the spotted owl at the time of listing.  Recent studies show no indication of reduced genetic variation and past bottlenecks in Washington, Oregon, or California (Barrowclough et al. 1999, Haig et al. in press, Henke et al. unpublished).  However, in Canada, the breeding population is estimated to be less than 33 pairs and annual population decline may be as high as 35 percent (Harestad 2004).  It is possible (but not necessarily the case) that the Canadian populations may be more adversely affected by issues related to small population size including inbreeding depression, genetic isolation, and reduced genetic diversity (Courtney et al. 2004).  Low and persistently declining populations throughout the northern portion of the species range (see “Population Trends” below) may be at increased risk of losing genetic diversity.

 

2.3.2.6 Climate change.  Climate change is a potential additional threat to spotted owl populations and is not explicitly addressed in the NWFP.  Climate change could have direct and indirect impacts on spotted owls and their prey.  However, the emphasis on maintenance of seral stage complexity and related organismal diversity in the Matrix under the NWFP should contribute to the resiliency of the federal forest landscape to the impacts of climate change (Courtney et al. 2004). 

 

2.4 Conservation Needs of the Spotted Owl

 

Based on the above assessment of threats, the spotted owl has the following habitat-specific and habitat-independent conservation (i.e., survival and recovery) needs:

 

2.4.1 Habitat-specific Needs

1.  Large blocks of suitable habitat to support clusters or local population centers of spotted owls (e.g., 15 to 20 breeding pairs) throughout the owl’s range;

 

2.  Suitable habitat conditions and spacing between local spotted owl populations throughout its range to facilitate survival and movement;

 

3.  Suitable habitat distributed across a variety of ecological conditions within the spotted owl’s range to reduce risk of local or widespread extirpation;

 

4.  A coordinated, adaptive management effort to reduce the loss of habitat due to catastrophic wildfire throughout the spotted owl’s range, and a research program to clarify whether these risk reduction methods are effective and to determine how owls use habitat treated to reduce fuels; and

 

5.  In areas of significant population decline, sustain the full range of survival and recovery options for this species in light of significant uncertainty.

 

2.4.2 Habitat-independent Needs

1.  A coordinated research and adaptive management effort to better understand and manage competitive interactions between spotted and barred owls; and

 

2.  Monitoring to better understand the risk that WNV and sudden oak death pose to spotted owls and, for WNV, research into methods that may reduce the likelihood or severity of outbreaks in spotted owl populations.

 

2.4.3 Conservation Strategy

Since 1990, various efforts have addressed the conservation needs of the spotted owl and attempted to formulate conservation strategies based upon these needs.  These efforts began with the ISC’s Conservation Strategy (Thomas et al. 1990); they continued with the designation of critical habitat (USFWS 1992b, the Draft Recovery Plan (USFWS 1992a)), and the Scientific Analysis Team report (Thomas et al. 1993), report of the Forest Ecosystem Management Assessment Team (Thomas and Raphael 1993); and culminated with the NWFP (USDA and USDI 1994a).  Each conservation strategy was based on the reserve design principles first articulated in the ISC’s report, which are summarized below. 

 

Species that are well distributed across their range are less prone to extinction than species confined to small portions of their range.

 

Large blocks of habitat, containing multiple pairs of the species, are superior to small blocks of habitat with only one to a few pairs.

 

Blocks of habitat that are close together are better than blocks far apart.

 

Habitat that occurs in contiguous blocks is better than habitat that is more fragmented.

 

Habitat between blocks is more effective as dispersal habitat if it resembles suitable habitat.

 

2.4.4 Federal Contribution to Recovery

The NWFP is the current conservation strategy for the spotted owl on federal lands.  It is designed around the conservation needs of the spotted owl and based upon the designation of a variety of land-use allocations whose objectives are either to provide for population clusters (i.e., demographic support) or to maintain connectivity between population clusters.  Several land-use allocations are intended to contribute primarily to supporting population clusters: Late-Succesional Reserves (LSRs), Managed Late-Successional Areas (MSLAs), Congressionally Reserved Areas (CRAs), Managed Pair Areas and Reserve Pair Areas.  The remaining land-use allocations [Matrix, AMAs, Riparian Reserves (RRs), Connectivity Blocks, and Administratively Withdrawn Areas (AWAs)] provide connectivity between habitat blocks intended for demographic support. 

 

The range-wide system of LSRs set up under the NWFP captures the variety of ecological conditions within the 12 different provinces to which spotted owls are adapted.  This design reduces the potential for extinction due to large catastrophic events in a single province.  Multiple, large LSRs in each province reduce the potential that spotted owls will be extirpated in any individual province and reduce the potential that large wildfires or other events will eliminate all habitat within a LSR.  In addition, LSRs are generally arranged and spaced so that spotted owls may disperse to two or more adjacent LSRs.  This network of reserves reduces the likelihood that catastrophic events will impact habitat connectivity and population dynamics within and between provinces.

 

Although FEMAT scientists predicted that spotted owl populations would decline in the Matrix over time, populations are expected to stabilize and eventually increase within LSRs, as habitat conditions improved over the next 50 to 100 years (Thomas and Raphael 1993, USDA and USDI 1994a and 1994b).  Based on the results of the first decade of monitoring, the NWFP’s authors cannot determine if the declining population trend will be reversed because not enough time has passed to provide the necessary measure of certainty (Lint 2005).  However, the results from the first decade of monitoring do not provide any reason to depart from the objective of habitat maintenance and restoration as described under the NWFP (Lint 2005).  It is recognized that other stressors, some already in action (e.g., barred owl) and some yet to be realized (West Nile virus), may complicate the conservation of the spotted owl.  Currently, the new reports generated on the science of the spotted owl offer few management recommendations to deal with the emerging threats facing the owl.  The redundancy and flexibility of the NWFP land use allocation system may prove to be the most appropriate strategy in responding to these unexpected challenges (Courtney et al. 2004).

 

Under the NWFP, the agencies anticipated a decline of spotted owl populations during the first decade of implementation.  Recent reports (Courtney et al. 2004, Anthony et al. 2004a) identified greater than expected spotted owl declines in Washington and northern portions of Oregon, and more stationary populations in southern Oregon and northern California.  The reports did not find a direct correlation between habitat conditions and changes in spotted owl populations.  Also, there is no evidence to suggest that dispersal habitat is currently limiting (Courtney et al. 2004, Lint 2005).  Even with the population decline, Courtney et al. (2004) noted that there is little reason to doubt the effectiveness of the core of the NWFP conservation strategy.

 

According to the USFWS (USDI, USFWS, November 2004), the current scientific information, including information showing spotted owl population declines, indicates that the spotted owl continues to meet the definition of a threatened species.  That is, populations are still relatively numerous over most of its historic range, which suggests that the threat of extinction is not imminent, and that the subspecies is not endangered even in the northern part of its range where greater than expected population declines were documented.

 

2.4.5 Conservation Efforts on Non-Federal Lands

FEMAT noted that limited Federal ownership in some areas constrained the ability to form an extensive reserve network to meet conservation needs of the spotted owl.  Thus, non-federal lands were an important contribution to the range-wide goal of achieving conservation and recovery of the spotted owl.  The Service’s primary expectations for private lands are for their contributions to demographic support (pair or cluster protection) to and/or connectivity with lands.  In addition, timber harvest within each state is governed by rules that may provide protection of spotted owls and/or their habitat to varying degrees.

 

Washington: In 1993, the State Forest Practices Board adopted rules (Forest Practices Board 1996) that would “contribute to conserving the spotted owl and its habitat on non-Federal lands” based on recommendations from a Science Advisory Group which identified important non-Federal lands and recommended roles for those lands in spotted owl conservation (Hanson et al. 1993, Buchanan et al. 1994).  Spotted owl-related Habitat Conservation Plans (HCPs) in Washington generally provide both demographic and connectivity support as recommended in these reports and the draft recovery plan (USFWS 1992a).

 

Oregon: The Oregon Forest Practices Act provides for protection of 70-acre core areas around known spotted owl nest sites, but it does not provide for protection of spotted owl habitat beyond these areas (ODF 2000).  In general, no large-scale spotted owl habitat protection strategy or mechanism currently exists for non-federal lands in Oregon.  The four spotted owl-related HCPs currently in effect address relatively few acres of land; however, they will provide some nesting habitat and connectivity over the next few decades.

 

California: In 1990, State Forest Practice Rules (FPRs), which govern timber harvest on private lands, were amended to require surveys for spotted owls in suitable habitat and to provide protection around activity centers (CDF 2001).  Under the FPRs, no timber harvest plan (THP) can be approved if it is likely to result in incidental take of Federally-listed species, unless authorized by a federal HCP.  The California Department of Fish and Game initially reviewed all THPs to ensure that take was not likely to occur; the Service took over that review function in 2000.  Several large industrial owners operate under Spotted Owl Management Plans that have been reviewed by the Service; the plans specify basic measures for spotted owl protection.  Three HCPs, authorizing take of spotted owls, have been approved.  Implementation of these plans will provide for spotted owl demographic and connectivity support to NWFP lands.

 

2.5 Current Condition of the Spotted Owl   

 

The current condition of the species incorporates the effects of all past human and natural activities or events that have led to the present-day status of the species and its habitat (USFWS and NMFS 1998).

 

2.5.1 Range-wide Habitat and Population Trends

2.5.1.1 Habitat Trends. The Service has used information provided by the FS, BLM, and National Park Service to update the habitat baseline conditions on Federal lands for spotted owls on several occasions since the spotted owl was listed in 1990.  The estimate of 7.4 million acres used for the NWFP in 1994 (USDA and USDI 1994a) was believed to be representative of the general amount of spotted owl habitat on these lands.  This baseline was used to track relative changes over time in the subsequently defined analyses.  The Service acknowledges that in 2005 a new map depicting suitable spotted owl habitat throughout the range of the spotted owl was produced as a result of the plan’s effectiveness monitoring program (Davis and Lint, in press).  However, this new habitat map is not yet available for use in tracking individual actions; therefore, the following analyses indicate changes to the baseline condition established in 1994.  In addition, there are no reliable estimates of spotted owl habitat on other land ownerships; consequently, consulted-on acres can be tracked, but not evaluated in the context of change with respect to a reference condition on non-federal lands.

 

2.5.1.2 Range-wide Analysis 1994 – 2001. In 2001, the Service conducted an assessment of habitat baseline conditions, the first since implementation of the NWFP (USFWS 2001).  This range-wide evaluation of habitat, compared to the FSEIS, was necessary to determine if the rate of potential change to spotted owl habitat was consistent with the change anticipated in the NWFP.  In particular, the Service considered habitat effects that were documented through the section 7 consultation process since 1994.  In general, the analytical framework of these consultations focused on the reserve or connectivity goals established by the NWFP land-use allocations (USDA and USDI 1994a), with effects expressed in terms of changes in suitable spotted owl habitat within those land-use allocations.  The Service determined that actions and effects were consistent with the expectations for implementation of the NWFP from 1994 to June, 2001 (USFWS 2001).

 

2.5.1.3 Range-wide Analysis 1994 – 2004 (first decade of the NWFP). This section updates the information considered in USFWS (2001), relying particularly on information in documents the Service produced pursuant to section 7 of the Act and information provided by NWFP agencies on habitat loss resulting from natural events (e.g., fires, windthrow, insect and disease). 

 

In 1994, about 7.4 million acres of suitable habitat were estimated to exist on federal lands (Table 6).  As of April 12, 2004, the Service had consulted on the proposed removal of 575,447 acres of spotted owl habitat range-wide (Table 7), of which 190,429 acres occurred on federal lands managed under the NWFP (Tables 8 and 9).  Federal lands were expected to experience an approximate 2.6 percent decline in suitable habitat due to all management activities (not just timber harvest) over the past decade, with about 167,134 acres[3] (about 2.3 percent) being removed by timber harvest.  These anticipated changes in suitable spotted owl habitat were consistent with the expectations for implementation of the NWFP.

 

Most management-related habitat loss was concentrated in the Oregon physiographic provinces (Tables 8 and 9).  In particular, the percentage of habitat to be removed from the Oregon Klamath Mountains province was relatively high (about 11 percent) in comparison to other provinces, most of which were characterized by less than a 4 percent decrease in habitat (based on Table 8).  Habitat removed from the Oregon Klamath Mountains province and the two Oregon Cascades provinces made up 44 percent and 36 percent of the habitat loss range-wide, respectively, since 1994.  In summary, habitat loss in Washington accounted for 9.06 percent of the range-wide loss, but it only resulted in a loss of 0.73 percent of available habitat on Federal lands in Washington (Table 8).  In Oregon, habitat loss accounted for 82.37 percent of the range-wide losses, but only 4.13 percent of available habitat on Federal lands in Oregon (Table 8).  Loss of habitat on federal lands in California accounted for 8.57 percent of the losses range-wide, but only 1.34 percent of habitat on federal lands in California (Table 8).  

 

Since 1994, habitat lost due to natural events was estimated at about 168,301 acres range-wide (Table 9).  About two-thirds of this loss was attributed to the Biscuit Fire that burned over 500,000 acres in southwest Oregon (Rogue River basin) and northern California in 2002.  This fire resulted in a loss of about 113,451 acres of spotted owl habitat, including habitat within five LSRs.   

 

There was little available information regarding spotted owl habitat trends on non-federal lands.  Yet, we do know that internal Service consultations conducted since 1992, have documented the eventual loss of 407,849[4] acres of habitat on non-federal lands.  Most of these losses have yet to be realized because they are part of large-scale, long-term HCPs.  

 

Since the analysis for the first decade (1994–2004) of the NWFP was conducted, the FS and BLM have reported revised estimates of fire impacts and that not all proposed and consulted-on effects occurred on the landscape.  Together these reports reduce the anticipated habitat loss since 1994.  Therefore the analysis above represents a worst-case assessment.   In addition, at the time of this assessment, we had no empirical information on increases in spotted owl habitat (on any ownership) resulting from habitat that had developed through vegetative succession (i.e., in-growth).  The 2005 NWFP spotted owl habitat trends report suggests that about 515,000 acres of younger forests may have grown into suitable habitat since 1994, range-wide (Davis and Lint, in press). 

 

2.5.1.4 Range-wide Analysis from 2004 (first decade) to the Present. This section updates the information considered in the first decade of the NWFP (April 13, 1994 – April 12, 2004) to the present writing of this BO.  In 1994, about 7.4 million acres of suitable habitat were estimated to exist on Federal lands.  As of April 2004, the Service had consulted on the removal of 575,447 acres of spotted owl habitat range-wide (Table 7), of which 190,429 acres occurred on Federal lands managed under the NWFP (Tables 8 and 9).  From April 12, 2004, to the present (January 6, 2006), the Service has consulted on the removal or downgrading of 11,323 acres of spotted owl habitat range-wide on Federal lands managed under the NWFP (190,429 acres consulted on for removal through April 12, 2004 (Tables 8 and 9) subtracted from 201,752 acres consulted on for removal through January 6, 2006 (Table 6)).  This amount of habitat loss (0.16 percent) is consistent with the expectations for timber management under the NWFP for the second decade of implementation, using the 2004 baseline of 7,038,368 acres of suitable habitat (1994 baseline with all suitable habitat losses subtracted out (Table 9).  Currently, an estimated 4,876,691 acres of spotted owl habitat in Reserves receive protection under the NWFP (Table 6).

 

2.5.1.5 Spotted Owl Numbers, Distribution, and Reproduction Trends.  There are no estimates of the historical population size and distribution of the spotted owl within preferred habitat, although spotted owls are believed to have inhabited most old-growth forests throughout the Pacific Northwest prior to modern settlement (mid-1800s), including northwestern California (USFWS 1989).  According to the final rule listing the spotted owl as threatened (USFWS 1990a), about 90 percent of the roughly 2,000 known spotted owl breeding pairs were located on federally managed lands, 1.4 percent on State lands, and 6.2 percent on private lands; the percent of spotted owls on private lands in northern California was slightly higher (Forsman et al. 1984, USFWS 1989, Thomas et al. 1990).

 

Gutiérrez (1994), using data from 1986-1992, tallied 3,753 known pairs and 980 singles throughout the range of the spotted owl.  At the time the NWFP was initiated (July 1, 1994), there were 5,431 known locations of, or site centers of spotted owl pairs or resident singles: 851 sites (16 percent) in Washington, 2,893 (53 percent) in Oregon, and 1,687 (31 percent) in California.  The actual population of spotted owls across the range was believed to be larger than either of these counts because some areas were, and remain, unsurveyed (USFWS 1992a, Thomas et al. 1993).  

 

Because existing survey coverage and effort are insufficient to produce reliable population-size estimates, researchers use other indices, such as demographic data, to evaluate trends in spotted owl populations.  Analysis of demographic data can provide an estimate of the rate and direction of population growth [i.e., lambda (λ)].  A λ of 1.0 indicates a stationary population (i.e., neither increasing nor decreasing), a λ less than 1.0 indicates a declining population, and a λ greater than 1.0 indicates a growing population.

 

In January 2004, at the spotted owl demographic meta-analysis workshop, two meta-analyses were conducted on the rate of population change using the re-parameterized Jolly-Seber method (λRJS); 1 meta-analysis for all 13 study areas and 1 meta-analysis for the 8 study areas that are part of the Effectiveness Monitoring Program of the NWFP (Anthony et al. 2004a).  Data were analyzed separately for individual study areas, as well as simultaneously across all study areas (true meta-analysis).  Estimates of λRJS ranged from 0.896-1.005 for the 13 study areas, and all but 1 (Tyee [TYE]) of the estimates were <1.0 suggesting population declines for most areas (Anthony et al. 2004a) (Figure 1).  There was strong evidence that populations on the Wenatchee (WEN), Cle Elum (CLE), Warm Springs (WSR), and Simpson (SIM) study areas declined during the study, and there also was evidence that populations on the RAI (Rainer), OLY (Olympic), COA (Oregon Coast Range), and HJA (HJ Andrews) study areas were decreasing (see Figure 1).  Precision of the λRJS estimates for RAI and OLY were poor and not sufficient to detect a difference from 1.00.  However, the estimate of λRJS for RAI (0.896) was the lowest of all of the areas.  Populations on TYE, KLA (Klamath), CAS (South Oregon Cascades), NWC (NW California), and HUP (Hoopa) appeared to be stationary during the study, but there was some evidence that the CAS, NWC, and HUP were declining (λRJS <1.00).  The weighted mean λRJS for all of the study areas was 0.963 (SE = 0.009, 95 percent CI = 0.945-0.981), suggesting that populations over all of the study areas were declining by about 3.7 percent per year from 1985-2003.  The mean λRJS for the 8 demographic monitoring areas on Federal lands was 0.976 (SE = 0.007, 95 percent CI = 0.962-0.990) and 0.942 (SE = 0.016, 95 percent CI = 0.910-0.974) for non-Federal lands, an average of 2.4 versus 5.8 percent decline, respectively, per year.  This suggests that spotted owl populations on Federal lands had better demographic rates than elsewhere, but interspersion of land ownership on the study areas confounds this analysis. 

 

The number of populations that have declined and the rate at which they have declined are noteworthy, particularly the precipitous declines on the four Washington study areas (WEN, CLE, RAI, OLY) (estimated at 30-50 percent population decline over 10 years) and WSR in Oregon (Anthony et al. 2004a).  Declines in adult survival rates may be an important factor contributing to declining population trends.  Survival rates declined over time on 5 of the 14 study areas: 4 study areas in Washington, which showed the sharpest declines, and 1 study area in the Klamath province of northwest California (Anthony et al. 2004a).  In Oregon, there were no time trends in apparent survival for four of six study areas, and remaining areas had weak non-linear trends.  In California, two study areas showed no trend, one showed a slight decline, and one showed a significant linear decline (Anthony et al. 2004a).  Like the trends in annual rate of population change, trends in adult survival rate showed clear declines in some areas, but not in others. 

 

British Columbia has a small population of spotted owls.  This population is relatively isolated and is apparently declining sharply and is absent from large areas of apparently-suitable habitat (Courtney et al. 2004).  Breeding populations have been estimated at fewer than 33 pairs and may be declining as much as 35 percent per year (Harestad et al. 2004).  The amount of interaction between spotted owls in Canada and the U.S. is unknown (Courtney et al. 2004).  The Canadian population has reached the point where it is now vulnerable to stochastic demographic events, that could cause further declines and perhaps extirpation and conditions are not likely to improve in the short term (Courtney et al. 2004, pgs. 3-26 to 3-27).


Table 6. Aggregate results of all adjusted, suitable habitat 1 acres on Northwest Forest Plan (NWFP) lands; range-wide changes by land use allocations from 1994 to January 6, 2006.

 

 

 

 

 

Reserves2

(Late- successional Reserves

(LSR), Managed Late-successional areas (MLSA) and Congressionally Reserved area (CRA))

Non-reserves3

(Administratively withdrawn area (AWA), Adaptive Management Areas (AMA), and Matrix)

TOTAL

 

LSR

MLSA

CRA

AWA

AMA

Matrix

Evaluation Baseline4

3227014

28900

1638652

300219

364268

1838045

7397098

Removed/Downgraded
(timber harvest only)5

7118

 1109

 30

 749

16158

153002

178166

Removed/Downgraded
(all other activities)6

 1550

0

1842

 54

478

19662

23586

Consultation Subtotal

8668

1109

1872

 803

16636

172664

201752

Removed/Downgraded
(natural disturbance)7

3451

309

2468

164

27

7238

13657

Net Changes from Land
Exchanges and Ownership Transfers

0

0

0

0

0

35

35

Other Activities Subtotal

3451

309

2468

164

27

7203

13622

Total Net Change

12119

1418

4340

967

16663

179867

215374

BASELINE BALANCE8

3214895

27482

1634312

299252

347605

1658178

7181724

Degraded9

31861

187

3301

410

11115

429782

476656

 

1  Nesting, roosting, foraging (NRF) habitat.  In California, suitable habitat is divided into two components; nesting-roosting (NR) habitat, and foraging (F) habitat.  The NR component most closely resembles NRF habitat in Oregon and Washington.  Due to differences in reporting methods, effects to suitable habitat compiled in this, and all subsequent tables include effects for nesting, roosting, and foraging (NRF) for 1994-6/26/2001.  After 6/26/2001, suitable habitat includes NRF for Washington and Oregon but only nesting and roosting (NR) for California.

2  Land-use allocations intended to provide large blocks of habitat to support clusters of breeding pairs.

3  Land-use allocations intended to provide habitat to support movement of spotted owls among reserves.

4  1994 FSEIS baseline (USDA and USDI 1994b).

5  Includes both effects reported by USFWS (2001) and subsequent effects compiled in the Spotted owl Consultation Effects Tracker (web application and database).  Total effects from the timber sale program, presented in the right column, is the value to contrast with the expectation that NWFP implementation would result in removal of 196,000 acres of NRF habitat per decade.

6  Includes NRF habitat effects from recreation, roads, minerals, and other non-timber programs of work.

7  Includes effects to NRF habitat resulting from wildfires (not from suppression efforts), insect and disease outbreaks, and other natural causes.  Information from all fires occurring since 1994 is not yet available for entry into the database and thus is not included here but is compiled in Table 9.

8  Calculated as (evaluation baseline) – [(total consulted-on changes) + (removed/downgraded as documented through TA process)].

9   Degraded habitat means that function remains the same, but quality is reduced.

Table 7. Changes to suitable1 habitat acres from activities subject to section 7 consultations and other causes range-wide from 1994 to April 2004.

 

Northwest Forest Plan (NWFP) Group /
Ownership

Consulted On
Habitat Changes2

Other Habitat Changes3

Removed/
Downgraded

Degraded

Removed/
Downgraded

Degraded

Federal -
Northwest
Forest

Plan

Bureau of Land Management (BLM)

61015

8627

760

0

Forest Service (FS)

92834

414868

10946

5109

National Park Service

908

2861

0

0

Multi-agency4

15175

23314

0

0

NWFP Subtotal

169932

449670

11706

5109

Other
Management
and
Conservation
Plans (OMCP)

Bureau of Indian Affairs
and Tribes

99062

27890

0

0

Habitat Conservation Plans

295889

14430

0

0

OMCP Subtotal

394951

42320

0

0

Other Federal Agencies & Lands5

241

434

28

70

Other Public & Private Lands6

10323

878

30240

20949

TOTAL Changes

575447

493302

41974

26128

 

1  Nesting, roosting, foraging habitat.  In California, suitable habitat is divided into two components; nesting – roosting (NR) habitat, and foraging (F) habitat.  The NR component most closely resembles NRF habitat in Oregon and Washington.  Due to differences in reporting methods, effects to suitable habitat compiled in this, and all subsequent tables include effects for nesting, roosting, and foraging (NRF) for 1994-6/26/2001.  After 6/26/2001, suitable habitat includes NRF for Washington and Oregon but only nesting and roosting (NR) for California.

2   Includes both effects reported by USFWS (2001) and subsequent effects compiled in the Spotted owl Consultation Effects Tracker (web application and database).

3  Includes effects to NRF habitat (as documented through technical assistance) resulting from wildfires (not from suppression efforts), insect and disease outbreaks, and other natural causes, private timber harvest, and land exchanges not associated with consultation.  Information from all fires occurring since 1994 is not yet available for entry into the database and thus is not included here but is compiled in Table 9.

4  The ‘Multi-agency’ grouping is used to lump a variety of NWFP mixed agency or admin unit consultations that were reported together prior to 6/26/2001, and cannot be split out.

5  Includes lands that are owned or managed by other Federal agencies not included in the NWFP.

6  Includes lands not covered by Habitat Conservation Plans that are owned or managed by states, counties, municipalities, and private entities.  Effects that occurred on private lands from right-of-way permits across FS and on BLM lands are included here.


Table 8. Aggregate results of all adjusted, suitable habitat1 acres affected by section 7 consultation for the northern spotted owl; baseline and summary of effects by State, physiographic province and land use function from 1994 to April 12, 2004 (the first decade of the Northwest Forest Plan).

 

Physiographic
Province4

Evaluation Baseline2

Habitat Removed/Downgraded3

% Provincial
Baseline
Affected

% Range-wide
Affected

Reserves5

Non-Reserves6

Total

Reserves5

Non-Reserves6

Total

WA

Olympic Peninsula

548483

11734

560217

67

24

91

-0.02

0.05

 

Eastern Cascades

506340

200509

706849

1746

4222

5968

-0.84

3.13

 

Western Cascades

864683

247797

1112480

249

10952

11201

-1.01

5.88

 

Western Lowlands

0

0

0

0

0

0

0

0

OR

Coast Range

422387

94190

516577

399

4145

4544

-0.88

2.39

 

Klamath Mountains

448509

337789

786298

2434

80394

82828

-10.53

43.5

 

Cascades East

247624

196035

443659

1813

12216

14029

-3.16

7.37

 

Cascades West

1012426

1033337

2045763

2926

52514

55440

-2.71

29.11

 

Willamette Valley

593

5065

5658

0

0

0

0

0

CA

Coast

47566

3928

51494

181

69

250

-0.49

0.13

 

Cascades

61852

26385

88237

0

4808

4808

-5.45

2.52

 

Klamath

734103

345763

1079866

1470

9800

11270

-1.04

5.92

Total

4894566

2502532

7397098

11285

179144

190429

-2.57

100

 

1  Nesting, roosting, foraging habitat.  In California, suitable habitat is divided into two components; nesting – roosting (NR) habitat, and foraging (F) habitat.  The NR component most closely resembles NRF habitat in Oregon and Washington.  Due to differences in reporting methods, effects to suitable habitat compiled in this, and all subsequent tables include effects for nesting, roosting, and foraging (NRF) for 1994-6/26/2001.  After 6/26/2001, suitable habitat includes NRF for Washington and Oregon but only nesting and roosting (NR) for California.

2  1994 FSEIS baseline (USDA and USDI 1994).

3  Includes both effects reported by USFWS (2001) and subsequent effects compiled in the Northern Spotted Owl Consultation Effects Tracking System (web application and database).

4  Defined by the NWFP as the twelve physiographic provinces, as presented in Figure 3&4-1 on page 3&4-16 of the FSEIS.

5  Land-use allocations intended to provide large blocks of habitat to support clusters of breeding pairs.

6  Land-use allocations intended to provide habitat to support movement of spotted owls among reserves.

 


 

Table 9.  Change in suitable spotted owl habitat from 1994 to April 12, 2004, resulting from Federal management actions (Mgmt) and natural events by physiographic province. 

 

 

 Physiographic Province

 

 

 

Northwest Forest Plan baseline

 

CAUSES OF HABITAT LOSS

 

 

TOTAL

 

% change

in Province

 

% of Total Effects

 

Mgmt1

 

Natural Events2

 

Olympic Peninsula

 

560,217

-91

-299

-390

-0.07

0.11

 

WA East Cascades

 

706,849

-5968

-5,754

-11722

-1.66

3.27

 

WA West Cascades

 

1,112,480

-11201

0

-11201

-1.01

3.12

 

Western Lowlands

 

0

0

0

0

0.00

0.00

 

OR Coast

 

516,577

-4544

-66

-4610

-0.89

1.29

 

OR Klamath Mountains

 

786,298

-82828

-117,622

-200450

-25.49

55.88

 

OR Cascades East

 

443,659

-14029

-4,008

-18037

-4.07

5.03

 

OR Cascades West

 

2,045,763

-55440

-24,583

-80023

-3.91

22.31

 

Willamette Valley

 

5,658

0

0

0

0.00

0.00

 

CA Coast

 

51,494

-250

-100

-350

-0.68

0.10

 

CA Cascades

 

88,237

-4808

0

-4808

-5.45

1.34

 

CA Klamath

 

1,079,866

-11270

-15,869

-27139

-2.51

7.57

 

TOTAL

 

7,397,098

-190429

-168,301

-358730

-4.85

100.00

1 Estimates from the NSO consultation effects tracker (USFWS 2005a). 

2 Data compiled by the U.S. Fish and Wildlife Service, Northern Spotted Owl Coordination Group.  Fires occurring in 2003 were not included as the data were not yet available.


 

Figure 1.  Physiographic provinces, northern spotted owl demographic study areas, and demographic trends (Anthony et al. 2004a).


3.0 Bald Eagle

 

A detailed account of the taxonomy, ecology, and reproductive characteristics of the bald eagle is found in the Pacific States Bald Eagle Recovery Plan (USFWS 1986), the final rule to reclassify the bald eagle from endangered to threatened in the 48 contiguous states (USFWS 1995), and the proposed rule to remove the bald eagle from the Endangered Species List in the 48 contiguous states (USFWS 1999).  History and trends in the status of bald eagle nests in Oregon are tracked annually by Isaacs and Anthony (2004).

 

In the Pacific Northwest, bald eagles typically nest in multi-layered, uneven-aged, coniferous stands with old-growth trees that are located within one mile of large bodies of water (Anthony et al. 1982).  Factors such as tree height, diameter, tree species, position on the landscape, distance from water, and distance from disturbance appear to influence nest selection.  Nest trees usually provide an unobstructed view of the associated water body.  Live, mature trees with deformed tops are often selected for nesting.  Availability of suitable trees for nesting and perching is critical for maintaining bald eagle populations.  Bald eagles often construct several nests within a territory and alternate between them from year to year.  Snags, trees with exposed lateral branches, or trees with dead tops are often present in nesting territories and are used for perching or as points of access to and from the nest.  Such trees also provide vantage points from which territories can be defended.

 

The bald eagle was listed as a threatened species in Oregon and Washington under the ESA on February 14, 1978.  This status is a result of past and present destruction of habitat, harassment, disturbance, shooting, electrocution, poisoning, a declining food base, and environmental contaminants.  Currently, the primary threats to bald eagles are habitat degradation and environmental contaminants in some areas. 

 

A Recovery Plan for the bald eagle in the Pacific states was issued in 1986 in accordance with Section 4(f)(1) of the Act.  The Pacific States Bald Eagle Recovery Plan established recovery population goals, habitat management goals, and management zones (i.e., Recovery Zones) for a seven-state Pacific Recovery Region (Recovery Region).  It outlined the following criteria for de-listing the bald eagle in the Recovery Region (USFWS 1986):

  1. There should be a minimum of 800 pairs nesting in the Recovery Region.
  2. These pairs should be producing at an annual average of at least 1.0 fledged young per pair, with an average success rate per occupied territory of not less than 65 percent over a 5-year period.
  3. To ensure an acceptable distribution of nesting pairs, population recovery goals must be met in at least 80 percent of the management zones (i.e., 38 out of 47 Recovery Zones) identified in the Recovery Plan.
  4. Wintering populations should be stable or increasing.  

Available information indicates that eagle populations are increasing range-wide.  The species’ status recovered sufficiently to warrant reclassification from endangered to threatened throughout the lower 48 states on July 12, 1995 (USFWS 1995); this action did not change the status of the species for Oregon and Washington where eagles remain listed as threatened. 

 

In Oregon, 441 breeding territories were occupied in 2004.  Productivity resulted in a 5-year average of 1.04 young per occupied territory.  Nesting success resulted in a 5-year average of 65 percent.  The annual population increase in Oregon averaged 6.4 percent for 1980-2003.  The net population increase in Oregon during 2004 was 5.5 percent.  Isaacs and Anthony (2004) suggested that population growth may be slowing or survey effort has not detected nesting in new areas.  Overall, the nesting population continues to grow, and expand into new areas (Isaacs and Anthony 2004).

 

3.1 Analysis of the bald eagle likely to be affected

 

The bald eagles’ successful reproduction is critical in their survival and recovery and although the potential for disturbance exists, the Management Standards - Specific to Bald Eagle prohibits disturbance to bald eagles nesting or raising fledglings.  Additionally, Management Standards - Specific to Bald Eagle also prohibits the disturbance of bald eagle at their winter roost sites.  Therefore, projects will either be at a distance beyond what is expected to disturb bald eagles or will occur outside time periods when the bald eagle is more sensitive, due to it being site-specific during breeding or winter roosting.  If projects occur within the disturbance distances for bald eagles, within their winter roosting period or breeding period (Table 4), then the projects are not covered under this consultation and will need to be consulted on separately.  Although no formal surveys will be conducted for bald eagles, nest and winter roost sites are highly visible.  Therefore, the Service concurs with the FS and BLM that the proposed activities may affect, but are not likely to adversely affect the bald eagle.

 

4.0 Environmental Baseline

 

The environmental baseline is defined as “the past and present impacts of all federal, state or private actions and other human activities in the action area, the anticipated impacts of all proposed federal projects in the action area that have already undergone formal or early section 7 consultation, and the impact of State and private actions which are contemporaneous with the consultation in process [50 CFR 402.02].

 

4.1 Spotted Owl

 

The action area is within the range of the spotted owl and occurs within suitable spotted owl habitat.  Although site specific information is lacking for the location of activities, the action area does contain about 1,340,581 acres of suitable habitat, an estimated 1,124 spotted owl activity centers (Table 10), and Anthony et al. (2004b) has current documentation of spotted owls using suitable habitat within the Willamette Planning Province. 

 

Although current surveys are not available for the entire action area, the Service assumes that suitable habitat is likely to be used by spotted owls.  The Service uses the following spotted owl life history traits to support this assumption.  First, spotted owl densities are greater in areas within nesting/roosting/foraging (NRF or also referred to as suitable) (typical 80 years old and greater) habitat relative to younger forest habitat (O’Halloran 1989, Simon-Jackson 1989, Thomas et al. 1990, Bart and Forsman 1992, USFWS 1992a, Forsman et al. 1996, Zabel 2003, Courtney et al. 2004).  Second, ‘floater’ owls fill the void and/or occupy habitat patches peripheral to occupied sites.  That is, if an owl site becomes unoccupied, the void is most often filled by another spotted owl (Gutierrez 1996, Forsman et al. 2002).  The fact that many spotted owls do not obtain territories until they are at least two years-old suggests that the number of floaters generally exceeds the number of available territories (Forsman et al. 2002), thus suggesting a high occupancy of available habitat.  Third, spotted owls exhibit high site fidelity to a territory, which is likely due to the species’ habitat specialization (Franklin 1992, Forsman et al. 2002, Courtney et al. 2004, Ackers and Anthony 2004).  Fourth, demographic parameters of survival and fecundity are affected by habitat.  For example, Franklin et al. (2000) showed that survival was positively correlated with the amount of interior older forest habitat.  Franklin et al. (2000) also concluded that owls in territories of higher habitat quality had greater survival during inclement weather than those in poorer quality habitat.  Additionally, Olson et al. (2004) and Anthony et al. (2002) have documented benefits of spotted owls using higher quality habitat.

 

Table 10.  Status of the northern spotted owl and its habitat within the Willamette Planning Province.

 

Total Acres

Protected

Unprotected

Total Acres

% of Total1

Total Acres

% of Total2

Acres within Boundary3

7,223,068

1,745,063

24%

5,369,039

74%

Acres of Ownership4

3,075,360

1,730,308

56%

1,344,562

44%

Suitable Habitat -
  Capable Acres5

2,577,280

1,405,073

55%

1,172,207

45%

Suitable Habitat -
  Current Acres

1,340,581

818,359

61%

519,861

39%

Spotted owl Activity     Centers6

1,124

374

33%

750

67%

Spotted owl Activity Centers >40%7

189

39

21%

150

79%

Spotted owl Activity Centers 30-40%8

796

297

37%

499

63%

Spotted owl Activity Centers <30%9

139

38

27%

101

73%

1  Acres in this column are comprised of:  Late Successional Reserves (LSR) and associated Riparian Reserves, 100-acre LSRs, Congressionally Withdrawn Areas, Riparian Reserves, District Designated Reserves, and Scenic Area Open Spaces. Spotted owl data are composed of LSR or designated wilderness areas only. These figures include those owl activity centers whose centers fall within the LSR or wilderness. The 1.2 mile radius surrounding the activity center may actually extend into unprotected areas.

2  Acres in this column are comprised of:  Matrix, Adaptive Management Areas, and Administratively Withdrawn Areas including associated Riparian Reserves. Administratively Withdrawn Areas are included in the unprotected column because technically these areas are not designed to provide spotted owl habitat but rather to serve some other function such as “recreation and visual areas, back country, and other areas where management emphasis precludes scheduled timber harvest” (Record of Decision A-4). The respective administrative land and resource management plans may protect and/or reduce the likelihood that spotted owl habitat located within Administratively Withdrawn Areas would be modified. Spotted owl data are composed of everything but LSR and designated wilderness data.

3  Acres include both private and federal lands.

4  Federal land only.

5  Acres that are either currently suitable spotted owl habitat or have the potential to become suitable in the future. Suitable habitat is defined as nesting, roosting, and foraging habitat.

6 Owl activity center data are updated only when new locations are identified (1996 or later). However, there are also many activity centers that have not been surveyed since 1996, and that may no longer be occupied by spotted owls.   

7  Spotted owl activity centers with greater than or equal to 1182 acres of suitable habitat within a 1.2 mile radius.

8  Spotted owl activity centers that have between 886 and 1182 acres of suitable habitat within a 1.2 mile radius.

9  Spotted owl activity centers with less than 886 acres of suitable habitat within a 1.2 mile radius.

 

 

4.1.1 Central Cascade Study Area

This spotted owl study area is within the Willamette National Forest and overlaps with part of the action area.  Pair occupancy has been stable since 1998, although simple occupancy (which includes all spotted owls detected) has decreased by 1-3 percent for three consecutive years.  Anthony et al. (2004b) believe this may be an indication that the non-territorial floater population is declining which would be consistent with the population rate of change recently reported (Anthony et al. 2004a).  Productivity was high in 2004, and is probably linked to the mild spring which contributes to early nesting and fledging periods (Anthony et al. 2004b).

 

Relative to the thirteen other spotted owl study areas represented in the 2004 meta-analysis, the demographic parameters estimated for the spotted owl population in the central Oregon Cascades were at intermediate levels (Anthony et al. 2004a). The greatest population declines are reported in the Oregon coast range and in all Washington study areas.  These study areas had negative time trends in fecundity and/or survival.  In contrast, spotted owl populations in southwestern Oregon and Northern California appeared to be relatively stable.  It is currently impossible to say what caused these patterns in population, due to differences in land use practices, climate, wildfire history, abundance of barred owls, latitudinal differences and differences in forest type.  It is likely that interactions among these and other factors are responsible for the observed patterns. (Anthony et al. 2004b), although, the fecundity and survival models for spotted owls within the Central Cascade study area do not support a negative effect from barred owls (Anthony et al. 2004a).

 

4.1.2 NWFP

The NWFP is the current conservation strategy for the spotted owl on federal lands.  It is designed around the conservation needs of the spotted owl and based on the designation of a variety of land-use allocations whose objectives are either to provide for population clusters (i.e., demographic support) or to maintain connectivity between population clusters.  Several land-use allocations are intended to contribute primarily to supporting population clusters: LSRs, Managed Late-Successional Areas (MSLAs), Congressionally Reserved Areas (CRAs), Managed Pair Areas and Reserve Pair Areas.  The remaining land-use allocations [Matrix, AMAs, Riparian Reserves (RRs), Connectivity Blocks, and Administratively Withdrawn Areas (AWAs)] provide connectivity between habitat blocks intended for demographic support. 

 

The range-wide system of LSRs set up under the NWFP captures the variety of ecological conditions within the 12 different provinces to which spotted owls are adapted.  This design reduces the potential for extinction due to large catastrophic events in a single province.  Multiple, large LSRs in each province reduce the potential that spotted owls will be extirpated in any individual province and reduce the potential that large wildfires or other events will eliminate all habitat within a LSR.  In addition, LSRs are generally arranged and spaced so that spotted owls may disperse to two or more adjacent LSRs.  This network of reserves reduces the likelihood that catastrophic events will impact habitat connectivity and population dynamics within and between provinces.

 

It has been eleven years since the adoption of the NWFP.  Thomas et al. (1990) argued that the spotted owl population trend should stabilize at a lower equilibrium size sometime with the next 100 years.  During the interim, there was an expectation that the rate of decline would slowly decrease as habitat loss was arrested and new habitat regenerated in the habitat conservation areas.  Similarly, the NWFP predicted a continuing decline of spotted owls until such time as new habitat developed (over a course of decades) (Appendix J of FSEIS) (Courtney et al. 2004).   Lint (2005) concluded that during the first ten years of the NWFP, the spotted owl habitat prognosis is seemingly correct.  Anthony et al. (2004a) stated that spotted populations appeared to be stationary in several study areas as a result of high survival and stable fecundity rates.   While the habitat provision of the NWFP is a necessary condition for spotted owls, it may not be a wholly sufficient provision (Courtney et al. 2004), given the spotted owl population declines observed in Washington (Anthony et al. 2004a).  After the first decade of the NWFP, the current science informs us that habitat is incredibly important to spotted owls and that the reserve network prescribed under the NWFP has been effective in maintaining and restoring owl habitat (Lint 2005).

 

The action area is located within the Oregon Western Cascades Physiographic Province and the Oregon Eastern Cascades Physiographic Province.

 

4.1.2.1 Oregon Western Cascades Physiographic Province.  This physiographic province is located in the geographic center of the spotted owl’s range and provides links with the Washington Cascades, Oregon Coast Range, and Klamath Mountains Physiographic Provinces. 

 

The 1994 FSEIS baseline (USDA and USDI 1994b) was 2,045,763 acres of suitable habitat on Federal lands within this province, with 55,453 acres being consulted on for removal through August 23, 2005, resulting in a decrease of 2.71 percent of the baseline. 

 

4.1.2.1 Oregon Eastern Cascades Physiographic Province.  Conservation objectives for this province include: maintaining existing connectivity within the province and with the Western Oregon Cascades Physiographic Province; providing connectivity with in the vicinity of the Columbia River Gorge; improving connectivity into northern California from the Eastern Oregon Cascades Physiographic Province.

 

The 1994 FSEIS baseline (USDA and USDI 1994b) was 443,659 acres of suitable habitat on Federal lands within this province, with 14,029 acres being consulted on for removal through August 23, 2005, resulting in a decrease of 3.16 percent of the baseline.

 

4.1.3 Role of the Action Area in the Survival and Recovery of the Spotted Owl

Matrix, AMAs, Riparian Reserves (RRs), and Administratively Withdrawn Areas (AWAs) have been designated to provide dispersal between habitat blocks.  Although currently spotted owls are successfully nesting and raising young within these areas, the long term conservation strategy does not rely on this habitat to maintain the spotted owl population.  The action area contains LSR and Congressionally Reserved Areas (CRAs), which are land use allocations (LUAs) that are intended to provide habitat blocks for the breeding population of spotted owls. 

 

Additionally, a small amount of non-federal lands are contained within the action area.  Because the non-federal lands occur within or adjacent to large blocks of Federal lands, the conservation needs of the spotted owls are expected to be met by the conservation strategy (NWFP) on Federal lands.

 

5.0 Effects of the Action

 

Effects of the action refer to the permanent or temporary direct and indirect effects of an action on the species, together with the effects of other activities that are interrelated and interdependent with that action, which will be added to the environmental baseline.  Indirect effects are those that are caused by the proposed action and occur later in time, but they are still reasonably certain to occur.

 

This section is organized in the following manner.  First, there is a general discussion of how the proposed action will affect habitat conditions or create disturbance to the spotted owl is presented.  Second, there is a specific discussion on the effect of each proposed activity type as it relates to habitat and disturbance issues for the spotted owl.

 

6.0 EFFECTS TO SPECIES

 

6.1 Spotted Owls

 

6.1.1 Effects to Spotted Owl Habitat

Habitat effects are summarized in Table 11. 

 

Table 11.  Effects of the proposed action on spotted owl habitat.

Activity

Effect to Spotted Owl

Rationale for Effect Determination

Removal of shrubs, small trees

 

MA,NLAA1

 

This activity is not likely to have a measurable effect on the ability of spotted owls to forage, nest, or shelter because the vast majority of shrubs and small trees will remain and the stands should still be able to function as spotted owl habitat.    

Removal of non-nest tree for tree topping, snag creation, or coarse woody debris

MA,NLAA

This activity will comprise a relatively small percentage of available habitat for spotted owl prey species or roost sites for spotted owls and is not likely to have a measurable effect on the ability of spotted owls to forage, nest, or shelter because trees will be left behind to create a more complex environment which will result in a greater carrying capacity for prey.

 

Removal of non-nests for road and dike repair

MA,NLAA

This activity is restricted to roads and is not likely to have a measurable effect on the ability of spotted owls to forage, nest, or shelter because only a few trees on the edge of the affected stand are likely to be removed. 

Removal of down wood

MA,NLAA

This activity is mainly restricted to roads and is not likely to have a measurable effect on the ability of spotted owls to forage, nest, or shelter because only a few trees on the edge of the affected stand are likely to be removed and the Northwest Forest Plan down wood requirements will ensure prey habitat is maintained at the stand level. 

1 MA,NLAA = may affect, but not likely to adversely affect

 

6.1.2 Disturbance Effects

Effects to spotted owls resulting from noise, human intrusion, or smoke-related disturbance are largely unknown.  In the most recent review of spotted owl research, none of these types of disturbance were considered a threat to the species (Courtney et al. 2004).  However, at the individual level, based on anecdotal information and effects to other bird species (Wesemann and Rowe 1987, Delaney et al. 1999, Delaney and Grubb 2001, Swarthout and Steidl 2001, USFWS 2005b, USFWS 2003), disturbance to owls is negatively related to stimulus distance and positively related to noise level, similar to results reported for bald eagles (Grubb and King 1991), gyrfalcon (Platt 1977), and other raptors (Awbrey and Bowles. 1990).  Therefore, the Service has concluded that significant noise, smoke and human presence in the canopy can result in a significant disruption of breeding, feeding, or sheltering behavior of the spotted owl such that it creates the potential for injury to the individuals (i.e., incidental take in the form of harass).   

 

For a significant disruption of spotted owl behavior to occur as a result of disturbance caused by a proposed action, the disturbance and the spotted owl(s) must be in close proximity to one another (see Table 4, USFWS 2005b, USFWS 2003).  Human presence on the ground is not expected to cause a significant disruption of behavior because spotted owls do not seem to be startled by human presence (USFWS 2005b). 

 

Spotted owl reactions to smoke and close human presence in the canopy, and excessive noise levels at or in the immediate vicinity of spotted owls are expected to include the following: flushing from the nest site, which would leave eggs or young exposed to predation; causing a juvenile to prematurely fledge, which would increase the young’s risk of predation; interrupting foraging activities, which would result in the reduced fitness or even mortality of an individual; or disrupting roosting activities which would cause a spotted owl to relocate.  A spotted owl that may be disturbed at a roost site is presumably capable of moving away from disturbance without a significant disruption of its behavior.  As stated in the Status of the Species section, spotted owls forage primarily at night.  Therefore, projects that occur during the day are not likely to disrupt its foraging behavior; the potential for effects is mainly associated with breeding behavior at an active nest site.   

 

Those proposed actions listed in Table 1 which generate noise above local ambient levels, involve tree climbing or smoke within the disruption distances of occupied habitat between March 1 and July 15 (critical nesting period), or which use large helicopters during the late breeding period (July 16 – September 30), are expected to generate disturbances that may adversely affect breeding spotted owls if they occur at or in proximity to active spotted owl nests. 

 

In the late breeding period, potential effects from disturbance decline because juvenile spotted owls are increasingly more capable of moving as the nesting season progresses.  Once capable of sustained flight, young owls are presumably able to distance themselves from disturbance and minimize their risk of predation.  To ensure that more than 86 percent of juvenile spotted owls in the Oregon Western Cascades Physiographic Province are able to move away from disturbances without increasing their risk of predation or harm, the critical nesting period is considered to be March 1 through July 15[5].  This is based on fledge data (Turner 1999) and includes an additional two weeks to allow for development of flight skills.  After July 15, it is estimated that most fledging spotted owls are capable of sustained flight and can move away from harmful disturbances.

 

Due to the significant potential for disturbance generated by large helicopters (Type I or II) and blasting, these activity may potentially create the likelihood of injury to fledglings throughout the entire breeding period (March 1 – September 30).  This is because of the larger distance that a juvenile spotted owl would have to travel to move away from these disturbances, which would put the young at greater risk from predation (Table 12).  Although, the proposed action only has large helicopter use and blasting proposed for the late breeding season (July 16 - September 30).

 

Table 12.  Non-habitat related effects from the proposed action and associated affects to northern spotted owls, if effects and individuals are within the disruption distances (Table 5).

Non-habitat related Effect

Time Period

Effect to Spotted Owls

Rationale for Effect Determination

Noise other than large helicopters

March 1 - July 15

MA,LAA1

Noise has been shown to significantly disrupt other birds causing reduced fitness and even death.  Although adult birds can move away from a noise source, nesting adults moving away from disturbance could cause increase predation to young, or missed feedings, which could result in a reduce fitness of the young and even death.

Noise and rotor wash associated with large helicopter use

July 16 -September 30

MA,LAA

Although this time period is in the late nesting period when most nestlings have fledge, the greater noise is believed to cause the parents travel greater distances to avoid the noise, and therefore the young who are not as capable flyers yet are potentially more susceptible to predation. Based on fledging data, spotted owls are still developing their flight and hunting skills and are being heavily cared for by the parents in this time period.

Smoke (prescribed burns)

March 1 - July 15

MA,LAA

Although data on smoke affects are lacking, the Service believes that smoke can cause adults to move off nest sites, therefore leaving eggs or young exposed to predation or resulting in lost feedings reducing the young’s fitness.

Blasting

July 16  -September 30

MA,LAA

Although this time period is in the late nesting period when most nestlings have fledge, the greater noise is believed to cause the parents travel greater distances to avoid the noise, and therefore the young who are not as capable flyers yet are potentially more susceptible to predation. Based on fledging data, spotted owls are still developing their flight and hunting skills and are being heavily cared for by the parents in this time period.

1 MA,LAA = may affect, and is likely to adversely affect

 

Although the Service has assumed disruption distances based on interpretation of best available information, the exact distances where different disturbances disrupt breeding are difficult to predict and can be influenced by a multitude of factors.  Site-specific information (e.g., topographic features, project length/duration or frequency of disturbance to an area) would also influence the degree of the effects to spotted owls.  The potential for noise producing activities creating the likelihood of injury to spotted owls is also dependent on the background or baseline levels in the environment.  In areas that are continually exposed to higher ambient noise levels (e.g. areas near well-traveled roads, campgrounds), spotted owls are probably less susceptible to small increases in disturbances because they are accustomed to such activities.  Spotted owls occur in areas near human activities and may habituate to certain levels of noise. 

 

To evaluate the potential for disturbance effects that involve a significant disruption of breeding, feeding, or sheltering behavior of the spotted owl such that it creates the likelihood of injury to the species (i.e., incidental take in the form of harass), the Service considered if the activities listed in Table 1 and nesting spotted owls will occur in proximity (within the disruption distance) of each other.  Although the proposed activities are expected to occur within suitable spotted owl habitat, there exact locations of activities are unknown and most of the action area is un-surveyed or lacks current spotted owl location data.  In the absence of this information, the Service has assumed occupancy at levels equal to the spotted owl density and nest attempt information within the Central Cascade Study Area (Anthony and Forsman 1997, Anthony 2005) to ascertain the likelihood of the proposed activities occurring within the disruption distance of an active spotted owl site.

 

The most recent data available for spotted owl crude density is from Anthony and Forsman (1997) at 0.0104 territories per km2.  Continued non-comprehensive surveys have documented the pair occupancy as being relatively stable since 1998 (Anthony 2005).  Additionally, S. Acker was contacted to discuss this trend,  he added that there has been some shifting of a few territories, but that the pair density is probably either stationary or a slight decline (Project Leader, Central Cascades Study Area, OR, pers. comm., 2006).  Although we feel this small variation is not significant, if it did skew the calculation it would be to overestimate the area of land associated with disturbing a spotted owl, because the number of active nest sites would be overestimated due to current levels are slightly lower.  Anthony (2005) estimated a mean percent of spotted owls nesting per year at 50 percent.

 

These demographic data were used to calculate the quantity of land-area where above-ambient noise would result in a disruption to nesting spotted owls.  This quantity of land, which could be associated with potential spotted owl nesting exposure, was then extended to the total amount of land within Willamette Planning Province, the action area.  Extrapolation of spotted owl nesting density and/or demographic data beyond the boundaries of a demographic study area is often debated (Anthony et al. 2004a).  This debate often centers on whether or not the spotted owl demographic areas are “representative” of the surrounding environment.  Thus, can the information be applied outside of the study area boundary?  Based on the comparative results by Anthony et al. (2004a), which showed the amount of spotted owl habitat was very similar within and surrounding the general study area, the Service believes that for the purpose of this analysis it is appropriate to make a density extrapolation for whether the proposed action will create the likelihood of injury. 

 

In calculating the potential exposure of nesting spotted owls to harassment, the Service started with 0.0104 territories per km2 or 1 territory per 2,377.15 acres.  Next, the Service used the concept that 50 percent of pairs that may breed/nest in a given year, based on information in Anthony (2004b), to approximate a nest density.  This results in one spotted owl nesting pair per 4,754.30 acres.   The Service is extrapolating this information to the Willamette Planning Province based on the comparative results by Anthony et al. (2005), as mentioned above.

 

The Service then combined the nesting pair density with the disruption distances to obtain an estimate of the percent of land associated with disruption (Table 13).  Even with a buffer to avoid the largest effects (helicopter, blasting and burning), nesting spotted owls are uncommon across the landscape. 

 


Table 13.  Percent of land associated with disruptions around nesting spotted owl pairs when the density is: one nesting pair/4,754 acres.

Disruption Distance (activity)

Percent of land associated with disruption around a nest when the density is: one nesting pair/4,754 acres

35 yards (heavy equipment & tree climbing)

0.02

65 yards (chainsaws)

0.06

120 yards (aircraft other than large helicopters)

0.20

180 yards (rock crushing)

0.44

0.25 mile (burning, blasting and large helicopter use)

2.64

 

Using the best available information, some of the assumptions used to evaluate the effects of the proposed action on spotted owls included:

 

·        Suitable spotted owl habitat is likely to be occupied at a rate of one occupied nest site per 4,754 acres; however, we do not have current survey information for most of the suitable spotted owl habitat in the action area.

·        Spotted owls normally do not nest every year and for the Willamette Planning Province the nesting rate is estimated at 50 percent, based on information form the West Cascades demographic study area (Anthony 2005).

·        Effects would only be adverse if the proposed activity occurred during the breeding season near an active spotted owl nest, and within the applicable disturbance distance for the activity, since adult owls are able to distance themselves from disturbances.  Therefore, adverse affects are linked to breeding when eggs/young have restricted mobility.

·        Although we do not know when or where most of the activities will occur, all have the potential to occur during the breeding season (see Description of the Proposed Action).

 

The proposed action is estimated to disrupt 37,104[6] acres of suitable spotted owl habitat or 2.77 percent of the suitable spotted owl habitat within the action area.  Based on best available information regarding potential spotted owl nest distribution within the action area (one nesting pair/4,754 acres), the Service has determined there is a potential for an overlap causing adverse effects, but not a likelihood for such an overlap.  An exact probability of the frequency of an overlap can not be determined since spotted owls and project locations are not randomly distributed throughout the action area.  Therefore, based on spotted owl nesting density in relation to the density of proposed projects, the Service determined disturbance from this activity type is not likely to adversely affect spotted owls because while adverse effects are possible, they are not reasonably certain to occur.

 

7.0 Effects of the Action BY ACTIVITY TYPE

 

7.1 Aerial Fertilization and Seeding

 

This activity is expected to generate above ambient noise levels due to use of aircraft.

 

7.1.1 Spotted owl

7.1.1.1 Habitat Modifications.  Habitat modification is not expected to occur with implementation of this activity. 

 

7.1.1.2 Disturbance.  Above ambient noise levels caused by this activity could adversely affect and potentially significantly disrupt the breeding behavior of spotted owls during their critical breeding period if the activity is implemented at or in proximity to an active nest site (see Table 12).  These adverse affects are anticipated to occur on an estimated 120 acres of suitable habitat, or 0.01 percent of suitable habitat within the action area.  If the nesting density was buffered with a 120 yard disruption distance due to aircraft use, then the buffer would occur on 0.20 percent of the habitat within the action area.  Therefore, based on the extent of the proposed projects under this activity type and best available information regarding potential spotted owl nest distribution within the action area (one nesting pair/4,754 acres) the Service has determined there is a potential for such an overlap, but not a likelihood.  Therefore, implementation of this activity during the entire spotted owl’s breeding period is not likely to adversely affect the spotted owl.  

 

For projects under this activity type and consulted on in this BO, the effect determination in the BA is likely to adversely affect spotted owls due to disturbance.  Based on the Service’s subsequent analysis we do not agree with BA’s determination of effects.  Based on spotted owl nesting density in relation to the density of proposed projects, the Service determined disturbance from this activity type is not likely to adversely affect spotted owls because while adverse effects are possible, they are not reasonably certain to occur.

 

7.2 Aerial Operations – Other

 

This activity is expected to generate above ambient noise levels due to use of aircraft.

 

7.2.1 Spotted owl

7.2.1.1 Habitat Modifications.  Habitat modification is not expected to occur with implementation of this activity. 

 

7.2.1.2 Disturbance.  Above ambient noise levels caused by this activity could adversely affect and potentially significantly disrupt the breeding behavior of spotted owls during their critical breeding period if the activity is implemented at or in proximity to an active nest site (see Table 12).  These adverse affects are anticipated to occur on an estimated 2,418 acres of suitable habitat, or 0.18 percent of suitable habitat within the action area.  If the nesting density was buffered with a 120 yard disruption distance due to aircraft use, then the buffer would occur on 0.20 percent of the habitat within the action area.  Therefore, based on the extent of the proposed projects under this activity type and best available information regarding potential spotted owl nest distribution within the action area (one nesting pair/4,754 acres) the Service has determined there is a potential for such an overlap, but not a likelihood.  Therefore, implementation of this activity during the entire spotted owl’s breeding period is not likely to adversely affect the spotted owl.  

 

For projects under this activity type and consulted on in this BO, the effect determination in the BA is likely to adversely affect spotted owls due to disturbance.  Based on the Service’s subsequent analysis we do not agree with BA’s determination of effects.  Based on spotted owl nesting density in relation to the density of proposed projects, the Service determined disturbance from this activity type is not likely to adversely affect spotted owls because while adverse effects are possible, they are not reasonably certain to occur.

 

7.3 Blasting

 

This activity is expected to generate above ambient noise levels due to blasting (blasting is prohibited during the critical nesting season) and remove the tops of some non-nest trees.

 

7.3.1 Spotted owl

7.3.1.1 Habitat Modifications.  Although this activity includes the removal of non-nest tree tops that could have adverse effects on spotted owl prey habitat or roost sites, it will comprise a relatively small percentage of available habitat for spotted owl prey species or roost sites for spotted owls.  Additionally, the trees will be left behind to create a more complex environment which will result in a greater carrying capacity for prey and in the future provide more spotted owls nest sites.  Therefore, implementation of this activity is likely to have a measurable beneficial effect for spotted owls.

 

The BA does not discuss effects to habitat, but due to the insignificant effects to the spotted owl the Service has determined that this activity type is not likely to adversely affect spotted owls due to habitat modifications.

 

7.3.1.2 Disturbance.  Above ambient noise levels caused by this activity could adversely affect and potentially significantly disrupt the breeding behavior of spotted owls during their critical breeding period if the activity is implemented at or in proximity to an active nest site (see Table 12).  These adverse affects are anticipated to occur on an estimated 16,210 acres of suitable habitat, or 1.21 percent of suitable habitat within the action area.  If the nesting density was buffered with a 0.25 mile disruption distance due to blasting in the late nesting season, then the buffer would occur on 2.64 percent of the habitat within the action area.  Therefore, based on the extent of the proposed projects under this activity type and best available information regarding potential spotted owl nest distribution within the action area (one nesting pair/4,754 acres) the Service has determined there is a potential for such an overlap, but not a likelihood.  Therefore, implementation of this activity during the entire spotted owl’s breeding period is not likely to adversely affect the spotted owl.  

 

For projects under this activity type and consulted on in this BO, the effect determination in the BA is likely to adversely affect spotted owls due to disturbance.  Based on the Service’s subsequent analysis we do not agree with BA’s determination of effects.  Based on spotted owl nesting density in relation to the density of proposed projects, the Service determined disturbance from this activity type is not likely to adversely affect spotted owls because while adverse effects are possible, they are not reasonably certain to occur.

 

7.4 Campgrounds/ Picnic areas/ Administrative Sites/Trail heads - Heavy Operations and Maintenance

 

This activity is expected to involve human presence on the ground and generate above ambient noise levels due to use of power equipment.

 

7.4.1 Spotted Owl

7.4.1.1 Habitat Modifications.  Habitat modification is not expected to occur with implementation of this activity. 

 

7.4.1.2 Disturbance.  Owls rarely nest at or immediately adjacent to road or edges (Kerns et al. 1992, Perkins 2000).  For that reason, implementation of this activity during the spotted owl’s breeding period is not likely to adversely affect the spotted owl.

 

For projects under this activity type and consulted on in this BO, the effect determination in the BA is likely to adversely affect spotted owls due to disturbance.  Based on the Service’s subsequent analysis we do not agree with BA’s determination of effects.  Based on spotted owl nesting density along roads/edges, the Service determined disturbance from this activity type is not likely to adversely affect spotted owls because while adverse effects are possible, they are not reasonably certain to occur.

 

7.5 Firewood/Post and Pole Sales

 

This activity is expected to generate above ambient noise levels due to use of chainsaws, and remove down wood and alder trees along road edges.

 

7.5.1 Spotted Owl

7.5.1.1 Habitat Modifications.  Although this activity includes removal of down wood that could have adverse effects on spotted owl prey habitat, it will occur only along road edges, which comprise a relatively small percentage of available habitat for spotted owl prey species.  Additionally, down wood that is not directly on the road/landing will only be removed when not located within a LSR and course woody debris remains in excess of the Northwest Forest Plan requirements, which will maintain a minimum levels of  prey habitat to ensure that the area is still able to provide for spotted owls foraging .  For these reasons, implementation of this activity is not likely to have a measurable effect on the spotted owl’s prey base and on the spotted owl.  This activity, when in spotted owl habitat, is restricted to along roads and is not likely to have a measurable effect on the ability of spotted owls to forage, nest, or shelter because only a few downed trees on the edge of the affected stand are likely to be removed.

 

The BA does not discuss effects to habitat, but due to the insignificant effects to the spotted owl the Service has determined that this activity type is not likely to adversely affect spotted owls due to habitat modifications.

 

7.5.1.2 Disturbance.  Owls rarely nest at or immediately adjacent to road or edges (Kerns et al. 1992, Perkins 2000).  For that reason, implementation of this activity during the spotted owl’s breeding period is not likely to adversely affect the spotted owl.

 

For projects under this activity type and consulted on in this BO, the effect determination in the BA is likely to adversely affect spotted owls due to disturbance.  Based on the Service’s subsequent analysis we do not agree with BA’s determination of effects.  Based on spotted owl nesting density along roads/edges, the Service determined disturbance from this activity type is not likely to adversely affect spotted owls because while adverse effects are possible, they are not reasonably certain to occur.

 

7.6 In-stream Activities/Terrestrial Habitat Restoration

 

This activity is expected to generate above ambient noise levels due to use of large helicopters and other equipment, and wind due to rotor wash of the helicopters (helicopter use is prohibited during the critical nesting season) and remove non-nest tree tops.

 

7.6.1 Spotted owl

7.6.1.1 Habitat Modifications.  Although this activity includes the removal of non-nest tree tops that could have adverse effects on spotted owl prey habitat or roost sites, it will comprise a relatively small percentage of available habitat for spotted owl prey species or roost sites for spotted owls.  Additionally, the trees will be left behind to create a more complex environment which will result in a greater carrying capacity for prey.  For that reason, implementation of this activity is likely to have a measurable beneficial effect on the spotted owl’s prey base for spotted owl.

 

The BA does not discuss effects to habitat, but due to the insignificant effects to the spotted owl the Service has determined that this activity type is not likely to adversely affect spotted owls due to habitat modifications.

 

7.6.1.2 Disturbance.  Above ambient noise levels caused by this activity could adversely affect and potentially significantly disrupt the breeding behavior of spotted owls during their critical breeding period or during their late breeding period when helicopters are used if the activity is implemented at or in proximity to an active nest site (see Table 12).  These adverse affects are anticipated to occur on an estimated 5,262 acres of suitable habitat, or 0.39 percent of suitable habitat within the action area.  If the nesting density was buffered with a 0.25 mile disruption distance due to helicopter use, then the buffer would occur on 2.64 percent of the habitat within the action area.  Therefore, based on the extent of the proposed projects under this activity type and best available information regarding potential spotted owl nest distribution within the action area (one nesting pair/4,754 acres) the Service has determined there is a potential for such an overlap, but not a likelihood.  Therefore, implementation of this activity during the entire spotted owl’s breeding period is not likely to adversely affect the spotted owl.

 

For projects under this activity type and consulted on in this BO, the effect determination in the BA is likely to adversely affect spotted owls due to disturbance.  Based on the Service’s subsequent analysis we do not agree with BA’s determination of effects.  Based on spotted owl nesting density in relation to the density of proposed projects, the Service determined disturbance from this activity type is not likely to adversely affect spotted owls because while adverse effects are possible, they are not reasonably certain to occur.

 

7.7 Invasive Plant Control

 

This activity is expected to generate above ambient noise levels due to use of power equipment, and remove shrubs.

 

7.7.1 Spotted owl

7.7.1.1 Habitat Modifications.  Although this activity includes the removal of shrubs that could have adverse effects on spotted owl prey habitat, it will occur only along roads or other edges, which comprise a relatively small percentage of available habitat for spotted owl prey species.  For that reason, implementation of this activity is not likely to have a measurable effect on the spotted owl’s prey base and on the spotted owl.    

 

The BA does not discuss effects to habitat, but due to the insignificant effects to the spotted owl the Service has determined that this activity type is not likely to adversely affect spotted owls due to habitat modifications.

 

7.7.1.2 Disturbance.  Owls rarely nest at or immediately adjacent to road or edges (Kerns et al. 1992, Perkins 2000).  For that reason, implementation of this activity during the spotted owl’s breeding period is not likely to adversely affect the spotted owl.

 

For projects under this activity type and consulted on in this BO, the effect determination in the BA is likely to adversely affect spotted owls due to disturbance.  Based on the Service’s subsequent analysis we do not agree with BA’s determination of effects.  Based on spotted owl nesting density along roads/edges, the Service determined disturbance from this activity type is not likely to adversely affect spotted owls because while adverse effects are possible, they are not reasonably certain to occur.     

 

7.8 Miscellaneous Special Uses (High Intensity)

 

This activity is expected to generate above ambient noise levels due to use of guns (black powder events), pile driving, motorcycles, or other above ambient noise not involving aircraft or blasting.

 

7.8.1 Spotted owl

7.8.1.1 Habitat Modifications.  Habitat modification is not expected to occur with implementation of this activity. 

 

7.8.1.2 Disturbance.  Above ambient noise levels caused by this activity could adversely affect and potentially significantly disrupt the breeding behavior of spotted owls during their critical breeding period if the activity is implemented at or in proximity to an active nest site (see Table 12).  These adverse affects are anticipated to occur on an estimated 160 acres of suitable habitat, or 0.01 percent of suitable habitat within the action area.  If the nesting density was buffered with a 65 yard disruption distance due to some noises may be greater than those produced by heavy equipment, then the buffer would occur on 0.06 percent of the habitat within the action area.  Therefore, based on the extent of the proposed projects under this activity type and best available information regarding potential spotted owl nest distribution within the action area (one nesting pair/4,754 acres) the Service has determined there is a potential for such an overlap, but not a likelihood.  Therefore, implementation of this activity during the entire spotted owl’s breeding period is not likely to adversely affect the spotted owl.     

 

7.9 Power Line Maintenance

 

This activity is expected to generate above ambient noise levels due to use of chainsaws or other power equipment, and remove underbrush and hardwoods along power lines.

 

7.9.1 Spotted owl

7.9.1.1 Habitat Modifications.  Although this activity includes the removal of underbrush and hardwoods that could have adverse effects on spotted owl prey habitat, it will occur only along power lines, which comprise a relatively small percentage of available habitat for spotted owl prey species.  For that reason, implementation of this activity is not likely to have a measurable effect on the spotted owl’s prey base and on the spotted owl.

 

The BA does not discuss effects to habitat, but due to the insignificant effects to the spotted owl the Service has determined that this activity type is not likely to adversely affect spotted owls due to habitat modifications.

 

7.9.1.2 Disturbance.  Owls rarely nest at or immediately adjacent to road or edges (Kerns et al. 1992, Perkins 2000).  For that reason, implementation of this activity during the spotted owl’s breeding period is not likely to adversely affect the spotted owl.

 

For projects under this activity type and consulted on in this BO, the effect determination in the BA is likely to adversely affect spotted owls due to disturbance.  Based on the Service’s subsequent analysis we do not agree with BA’s determination of effects.  Based on spotted owl nesting density along roads/edges, the Service determined disturbance from this activity type is not likely to adversely affect spotted owls because while adverse effects are possible, they are not reasonably certain to occur.             

 

7.10 Precommercial thinning/stand maintenance/ riparian site preparation

 

This activity is expected to generate above ambient noise levels due to use of chainsaws, and remove underbrush and hardwoods along streams or adjacent to habitat.

 

7.10.1 Spotted owl

7.10.1.1 Habitat Modifications. Although this activity includes the removal of underbrush and hardwoods that could have adverse effects on spotted owl prey habitat, it will occur only along streams, which comprise a relatively small percentage of available habitat for spotted owl prey species.  For that reason, implementation of this activity is not likely to have a measurable effect on the spotted owl’s prey base and on the spotted owl.

 

The BA does not discuss effects to habitat, but due to the insignificant effects to the spotted owl the Service has determined that this activity type is not likely to adversely affect spotted owls due to habitat modifications.

 

7.10.1.2 Disturbance.  Above ambient noise levels caused by this activity could adversely affect and potentially significantly disrupt the breeding behavior of spotted owls during their critical breeding period if the activity is implemented at or in proximity to an active nest site (see Table 12).  These adverse affects are anticipated to occur on an estimated 3,670 acres of suitable habitat, or 0.27 percent of suitable habitat within the action area.  If the nesting density was buffered with a 65 yard disruption distance due to chainsaw use, then the buffer would occur on 0.06 percent of the habitat within the action area.  Therefore, based on the extent of the proposed projects under this activity type and best available information regarding potential spotted owl nest distribution within the action area (one nesting pair/4,754 acres) the Service has determined there is a potential for such an overlap, but not a likelihood.  Therefore, implementation of this activity during the entire spotted owl’s breeding period is not likely to adversely affect the spotted owl.

 

For projects under this activity type and consulted on in this BO, the effect determination in the BA is likely to adversely affect spotted owls due to disturbance.  Based on the Service’s subsequent analysis we do not agree with BA’s determination of effects.  Based on spotted owl nesting density in relation to the density of proposed projects, the Service determined disturbance from this activity type is not likely to adversely affect spotted owls because while adverse effects are possible, they are not reasonably certain to occur.

 

7.11 Prescribed Burning

 

This activity is expected to generate smoke from prescribed burning, generate above ambient noise levels due to use of power equipment, and remove shrubs, down wood and small trees.

 

7.11.1 Spotted owl

7.11.1.1 Habitat Modifications.  Although this activity includes the removal of the under story (shrubs, down wood and small trees) for fuels reduction that could have adverse effects on spotted owl prey habitat, it will occur in stands near human development that have a high down wood component which is a relatively small percentage of available habitat for spotted owl prey species.  Additionally, large coarse woody debris will be maintained and shrubs and small trees tend to return within a year after a burn.  For that reason, implementation of this activity is not likely to have a measurable effect on the spotted owl’s prey base and on the spotted owl.

 

The BA does not discuss effects to habitat, but due to the insignificant effects to the spotted owl the Service has determined that this activity type is not likely to adversely affect spotted owls due to habitat modifications.

           

7.11.1.2 Disturbance.  Above ambient noise and smoke levels caused by this activity could adversely affect and potentially significantly disrupt the breeding behavior of spotted owls during their critical breeding period if the activity is implemented at or in proximity to an active nest site (see Table 12).  These adverse affects are anticipated to occur on an estimated 1,570 acres of suitable habitat, or 0.12 percent of suitable habitat within the action area.  If the nesting density was buffered with a 0.25 mile disruption distance due to smoke, then the buffer would occur on 2.64 percent of the habitat within the action area.  Therefore, based on the extent of the proposed projects under this activity type and best available information regarding potential spotted owl nest distribution within the action area (one nesting pair/4,754 acres) the Service has determined there is a potential for such an overlap, but not a likelihood.  Therefore, implementation of this activity during the entire spotted owl’s breeding period is not likely to adversely affect the spotted owl.

 

For projects under this activity type and consulted on in this BO, the effect determination in the BA is likely to adversely affect spotted owls due to disturbance.  Based on the Service’s subsequent analysis we do not agree with BA’s determination of effects.  Based on spotted owl nesting density in relation to the density of proposed projects, the Service determined disturbance from this activity type is not likely to adversely affect spotted owls because while adverse effects are possible, they are not reasonably certain to occur.

 

7.12 Road and Dike Repair

 

This activity is expected to generate above ambient noise levels due to the use of power equipment and remove non-nest trees.

 

7.12.1 Spotted owl

7.12.1.1 Habitat Modifications.  Although this activity includes the removal of non-nest trees that could have adverse effects on spotted owl prey habitat and quantity of roost sites, it will occur only along road edges, which comprise a relatively small percentage of available roost sites and habitat for spotted owl prey species.  For that reason, implementation of this activity is not likely to have a measurable effect on the owl’s prey base or quantity of roost sites on the owl.

 

The BA does not discuss effects to habitat, but due to the insignificant effects to the spotted owl the Service has determined that this activity type is not likely to adversely affect spotted owls due to habitat modifications.

 

7.12.1.2 Disturbance.  Owls rarely nest at or immediately adjacent to road or edges (Kerns et al. 1992, Perkins 2000).  For that reason, implementation of this activity during the spotted owl’s breeding period is not likely to adversely affect the spotted owl.

 

For projects under this activity type and consulted on in this BO, the effect determination in the BA is likely to adversely affect spotted owls due to disturbance.  Based on the Service’s subsequent analysis we do not agree with BA’s determination of effects.  Based on spotted owl nesting density along roads/edges, the Service determined disturbance from this activity type is not likely to adversely affect spotted owls because while adverse effects are possible, they are not reasonably certain to occur.  

 

7.13 Rock Quarry Sites and Operations

 

This activity is expected to generate above ambient noise levels due to use of rock crushers and other power equipment.

 

7.13.1 Spotted owl

7.13.1.1 Habitat Modifications.  Habitat modification is not expected to occur with implementation of this activity. 

 

7.13.1.2 Disturbance. Above ambient noise levels caused by this activity could adversely affect and potentially significantly disrupt the breeding behavior of spotted owls during their critical breeding period or during their late breeding period when blasting is used if the activity is implemented at or in proximity to an active nest site (see Table 12).  These adverse affects are anticipated to occur on an estimated 256 acres of suitable habitat, or 0.02 percent of suitable habitat within the action area.  If the nesting density was buffered with a 0.25 mile disruption distance due to blasting, then the buffer would occur on 2.64 percent of the habitat within the action area.  Therefore, based on the extent of the proposed projects under this activity type and best available information regarding potential spotted owl nest distribution within the action area (one nesting pair/4,754 acres) the Service has determined there is a potential for such an overlap, but not a likelihood.  Therefore, implementation of this activity during the entire spotted owl’s breeding period is not likely to adversely affect the spotted owl.

 

For projects under this activity type and consulted on in this BO, the effect determination in the BA is likely to adversely affect spotted owls due to disturbance.  Based on the Service’s subsequent analysis we do not agree with BA’s determination of effects.  Based on spotted owl nesting density in relation to the density of proposed projects, the Service determined disturbance from this activity type is not likely to adversely affect spotted owls because while adverse effects are possible, they are not reasonably certain to occur.   

 

7.14 Salvage

 

This activity is expected to generate above ambient noise levels due to use of chainsaws, and remove down trees along roads and within the Matrix land use allocation.

 

7.14.1 Spotted owl

7.14.1.1 Habitat Modifications.  Although this activity includes the removal of non-nest trees that could have adverse effects on spotted owl prey habitat and quantity of roost sites, it will occur mainly along road edges which comprise a relatively small percentage of available roost sites and habitat for spotted owl prey specie or involve a single logs within a Matrix land use allocation stand which has coarse woody debris in excess of the Northwest Forest Plan requirements to maintain prey habitat for spotted owl foraging.  For these reasons, implementation of this activity is not likely to have a measurable effect on the owl’s prey base or quantity of roost sites on the owl.    

 

The BA does not discuss effects to habitat, but due to the insignificant effects to the spotted owl the Service has determined that this activity type is not likely to adversely affect spotted owls due to habitat modifications.

 

7.14.1.2 Disturbance.  Above ambient noise levels caused by this activity could adversely affect and potentially significantly disrupt the breeding behavior of spotted owls during their critical breeding period if the activity is implemented at or in proximity to an active nest site (see Table 12).  These adverse affects are anticipated to occur on an estimated 345 acres of suitable habitat, or 0.03 percent of suitable habitat within the action area.  If the nesting density was buffered with a 65 yard disruption distance due to chainsaw use, then the buffer would occur on 0.06 percent of the habitat within the action area.  Therefore, based on the extent of the proposed projects under this activity type and best available information regarding potential spotted owl nest distribution within the action area (one nesting pair/4,754 acres) the Service has determined there is a potential for such an overlap, but not a likelihood.  Therefore, implementation of this activity during the entire spotted owl’s breeding period is not likely to adversely affect the spotted owl. 

 

For projects under this activity type and consulted on in this BO, the effect determination in the BA is likely to adversely affect spotted owls due to disturbance.  Based on the Service’s subsequent analysis we do not agree with BA’s determination of effects.  Based on spotted owl nesting density in relation to the density of proposed projects, the Service determined disturbance from this activity type is not likely to adversely affect spotted owls because while adverse effects are possible, they are not reasonably certain to occur.

 

7.15 Special Forest Products

 

This activity is expected to generate above ambient noise levels due to use of small power equipment including chainsaws, and remove shrubs and small trees (Christmas trees).

 

7.15.1 Spotted owl

7.15.1.1 Habitat Modifications. Although this activity includes the removal of underbrush and small trees that could have adverse effects on spotted owl prey habitat, it will occur only along road edges, which comprise a relatively small percentage of available habitat for spotted owl prey species.  For that reason, implementation of this activity is not likely to have a measurable effect on the spotted owl’s prey base and on the spotted owl.

 

The BA does not discuss effects to habitat, but due to the insignificant effects to the spotted owl the Service has determined that this activity type is not likely to adversely affect spotted owls due to habitat modifications.

 

7.15.1.2 Disturbance.  Above ambient noise levels caused by this activity could adversely affect and potentially significantly disrupt the breeding behavior of spotted owls during their critical breeding period if the activity is implemented at or in proximity to an active nest site (see Table 12).  These adverse affects are anticipated to occur on an estimated 10 acres of suitable habitat, or less than 0.01 percent of suitable habitat within the action area.  If the nesting density was buffered with a 65 yard disruption distance due to chainsaw use then the buffer would occur on 0.06 percent of the habitat within the action area.  Therefore, based on the extent of the proposed projects under this activity type and best available information regarding potential spotted owl nest distribution within the action area (one nesting pair/4,754 acres) the Service has determined there is a potential for such an overlap, but not a likelihood.  Therefore, implementation of this activity during the entire spotted owl’s breeding period is not likely to adversely affect the spotted owl.

 

For projects under this activity type and consulted on in this BO, the effect determination in the BA is likely to adversely affect spotted owls due to disturbance.  Based on the Service’s subsequent analysis we do not agree with BA’s determination of effects.  Based on spotted owl nesting density in relation to the density of proposed projects, the Service determined disturbance from this activity type is not likely to adversely affect spotted owls because while adverse effects are possible, they are not reasonably certain to occur.     

 

7.16 Trail Reconstruction, Maintenance, and Removal

 

This activity is expected to generate above ambient noise levels due to use of chainsaws or other power equipment, and remove shrubs and/or small trees.

 

7.16.1 Spotted owl

7.16.1.1 Habitat Modifications.  Although this activity includes the removal of underbrush and small trees that could have adverse effects on spotted owl prey habitat, it will occur only along trails, which comprise a relatively small percentage of available habitat for spotted owl prey species.  For that reason, implementation of this activity is not likely to have a measurable effect on the spotted owl’s prey base and on the spotted owl.

 

The BA does not discuss effects to habitat, but due to the insignificant effects to the spotted owl the Service has determined that this activity type is not likely to adversely affect spotted owls due to habitat modifications.

 

7.16.1.2 Disturbance.  Above ambient noise levels caused by this activity could adversely affect and potentially significantly disrupt the breeding behavior of spotted owls during their critical breeding period if the activity is implemented at or in proximity to an active nest site (see Table 12).  These adverse affects are anticipated to occur on an estimated 6,563 acres of suitable habitat, or 0.49 percent of suitable habitat within the action area.  If the nesting density was buffered with a 65 yard disruption distance due to chainsaw use then the buffer would occur on 0.06 percent of the habitat within the action area.  Therefore, based on the extent of the proposed projects under this activity type and best available information regarding potential spotted owl nest distribution within the action area (one nesting pair/4,754 acres) the Service has determined there is a potential for such an overlap, but not a likelihood.  Therefore, implementation of this activity during the entire spotted owl’s breeding period is not likely to adversely affect the spotted owl.

 

For projects under this activity type and consulted on in this BO, the effect determination in the BA is likely to adversely affect spotted owls due to disturbance.  Based on the Service’s subsequent analysis we do not agree with BA’s determination of effects.  Based on spotted owl nesting density in relation to the density of proposed projects, the Service determined disturbance from this activity type is not likely to adversely affect spotted owls because while adverse effects are possible, they are not reasonably certain to occur.

 

7.17 Summary of affects

 

7.17.1 Spotted owls

The Service concludes that although the activities in the proposed action have the potential to adversely affect breeding spotted owls, it is not reasonably certain that an active spotted owl nest would occur at or near a proposed project due to the low density of actively nesting spotted owls and the small proportion of the action area that will be disturbed.  Therefore, all activities are not likely to adversely affect spotted owls.

 

8.0 COMBINED Effects to the populations

 

8.1 Willamette Planning Province

Adverse affects are not expected to occur in conjunction with the implementation of this activity that would affect spotted owls. 

 

8.2 Oregon Western Cascades Physiographic Province

Adverse affects are not expected to occur in conjunction with the implementation of this activity that would affect spotted owls. 

 

8.3 Oregon Eastern Cascades Physiographic Province

Adverse affects are not expected to occur in conjunction with the implementation of this activity that would affect spotted owls. 

 

8.4 Range-wide

Adverse affects are not expected to occur in conjunction with the implementation of this activity that would affect spotted owls. 

 

8.5 Relationship of affects to survival and recovery of the spotted owl

The effects discussed above are not considered significant for the following reasons:

 

1.  The affected areas will still meet the conservation needs of the spotted owl because the quantity of suitable spotted owl habitat will not be reduced and the quantity of dispersal spotted owl habitat will not be reduced;

 

2.  The affected areas are a small portion of large blocks of spotted owl suitable and dispersal habitat within the Willamette Planning Province;

 

 3.  Potential effects from disturbance to reproductive success are related to a spotted owl pair’s nest site, located within an estimated 2955 acre home range, and the reproduction status of the pair, which has been shown to be variable from year to year.  Therefore, given that the spotted owl has a large home range and that spotted owl pairs do not nest every year, the likelihood of affecting reproduction at a given site is small;

 

4.  Potential effects from disturbance affecting foraging spotted owls is minimal because spotted owls are primarily nocturnal and most of the activities will occur during the day time; and

 

5.  Although the project level under each activity type can not be exceeded under this consultation, it is to be noted that the agencies estimated the amount of habitat within disruption distances of proposed projects.

                      

9.0 Cumulative Effects

 

Cumulative effects include the effects of future State, tribal, local or private actions that are reasonably certain to occur within the action area considered in this BO.  Future federal actions that are unrelated to the proposed action are not considered in this section because they require separate consultation pursuant to section 7 of the Act.

 

Although the Willamette Planning Province is lacking information on spotted owls or spotted owl habitat for non-federal lands within the action area, non-federal lands within the Willamette Planning Province boundaries usually only support marginal habitats, and do not notably contribute to the viability of the spotted owl.  These lands, however, support some dispersal habitat for spotted owls and may contribute to the reproduction, health, and condition of spotted owls on adjacent Federal land.  Habitat conditions on these lands are not expected to improve significantly within the foreseeable future and, as a result, are not expected to contribute to the survival and recovery of the spotted owl.

 

Cumulative effects to spotted owls are an ongoing concern and will likely continue in the future within the action area.  To date, the Oregon Forest Practice Rules have not adopted regulations that provide adequate protection to spotted owl sites or a mechanism to identify sites on the landscape (e.g. surveys in suitable habitat).  The rules require protection of a 70-acre core area around active nest sites only, and do not provide any protection or conservation of other surrounding habitat.  For a species that requires up to several thousand acres of habitat to persist, these rules allow for the progressive elimination of active spotted owl sites.  Removal of large amounts of habitat around 70-acre cores will eventually render the core nest areas non-functional and displacement of spotted owls is the likely outcome. 

 

10.0 Conclusion

 

After reviewing the current status of the spotted owl, the environmental baseline for the action area, the effects of the proposed activities on spotted owls, and the cumulative effects, it is the Service’s biological opinion that the activities, as proposed, are not likely to jeopardize the continued existence of the spotted owl.

 

We reached these conclusions because no cumulative effects are anticipated that would alter the Effects of the Action findings that implementation of the proposed action is compatible with maintaining the role of the action area in the survival and recovery of the spotted owl with respect to suitable and dispersal habitat.  Implementation of the proposed action is not expected to inhibit spotted owl dispersal at the Willamette Planning Province, Oregon Western Cascades Physiographic Province, Oregon Eastern Cascades Physiographic Province or range-wide (NWFP) scales; and the potential affects from disturbance to reproduction success is related to an owl pair’s nest site, located within an estimated 2,955 acres home range, and the reproductive status of the pair, which has been shown to vary from year to year.  Therefore, given that the spotted owl has a large home range and that spotted owl pairs do not nest every year, the likelihood of affecting reproduction at a given site is small.

 

Incidental Take Statement

 

Section 9 of the Act prohibits taking (harass, harm, pursue, hunt, shoot, wound, kill, trap, capture or collect, or attempt to engage in any such conduct) of listed species of fish or wildlife without a special exemption.  Harm is further defined to include significant habitat modification or degradation that results in death or injury to listed species by significantly impairing behavioral patterns such as breeding, feeding, or sheltering.  Harass is defined as actions that create the likelihood of injury to listed species to such an extent as to significantly disrupt normal behavior patterns which include, but are not limited to, breeding, feeding or sheltering.  Incidental take is any take of listed animal species that results from, but is not the purpose of, carrying out an otherwise lawful activity conducted by the federal agencies or the applicant.  Under the terms of section 7(b)(4) and section 7(o)(2), take that is incidental to and not intended as part of the agencies= action is not prohibited provided that such take is in compliance with the terms and conditions of this incidental take statement.  Section 7 (b)(4) and 7 (o)(2) of the Act do not apply to the incidental take of listed plant species.  However, protection of listed plants is provided to the extent that the Act requires a federal permit for the removal or reduction to possession of endangered plants from areas under federal jurisdiction, or for any act that would remove, cut, dig up, or damage or destroy any such species on any other area in knowing violation of any regulation of any state or in the course on any violation of a state criminal trespass law.

 

11.0 Amount or Extent of Take

 

No take is anticipated as a result of this proposed action because there is only a potential for effects that conform to the regulatory definition of take; that is, the proposed action creates the potential for injury (i.e., harass) to spotted owls, but not a likelihood.

 

12.0 Reasonable and Prudent Measures

 

Since Management Standards common to all activities (section 1.2), were developed as part of the proposed action which included measures to reduce incidental take and included monitoring of projects (1.2 General Standards, number 4), no reasonable measures are proposed.

 

13.0 Terms and Conditions

 

Not applicable

 

14.0 Conservation Recommendations

 

Section 7(a)(1) of the Act directs federal agencies to use their authorities to further the purposes of the Act by implementing conservation programs for the benefit of endangered and threatened species. Conservation recommendations are discretionary agency activities designed to minimize or avoid adverse effects of a proposed action on listed species or designated critical habitat, to assist in the implementation of recovery plans or to obtain information.

 

The Service believes the following conservation recommendation will reduce the impact of the proposed action on nesting spotted owls within the action area:

 

  1. Delay activities that may disturb spotted owls as late as possible into the nesting season.

 

In order for the Service to be kept informed of actions that minimize or avoid adverse effects or benefit listed species or their habitats, the Service requests notification regarding the implementation of any conservation recommendation.

 

15.0 Reinitiation Notice

 

This concludes formal consultation on the actions outlined in your Biological Assessment.  As provided in (50 CFR § 402.16), reinitiation of formal consultation is required where discretionary federal agency involvement or control over the action has been maintained (or is authorized by law) and if: (1) the amount or extent of incidental take is exceeded; (2) new information reveals effects of the agencies’ action that may affect listed species or critical habitat in a manner or to an extent not considered in this BO; (3) the agency action is subsequently modified in a manner that causes an effect to the listed species or critical habitat that was not considered in this BO; or (4) a new species is listed or critical habitat designated that may be affected by the action. In instances where the amount or extent of incidental take is exceeded, any operations causing such take must cease pending re-initiation of formal consultation.   

LITERATURE CITED

 

Ackers, S. and R. J. Anthony.  2004.  Demographic characteristics of northern spotted owls in the central Cascades of Oregon.  Annual Progress Report.  Oregon Coop. Wildlife Research Unit, OSU, Corvallis, OR.

Anthony, R.G., and E.D. Forsman.  1997.  The ecology of northern spotted owls on the Willamette National Forest, Oregon:  habitat use and demography.  Annual Progress Report.  Oregon Coop. Fish and Wildlife Research Unit, Oregon State Univ., Corvallis, OR.

Anthony, R.  2005.  The ecology of northern spotted owls (Strix occidentalis caurina) on the Willamette National Forest; Annual Research Report-Unpublished.  Oregon State University.

Anthony, R.G., E.D. Forsman, A.B. Franklin, D.R. Anderson, K.P. Burnham, G.C. White, C.J. Schwarz, J. Nichols, J.E. Hines, G.S. Olson, S.H. Ackers, S. Andrews, B.L. Biswell, P.C. Carlson, L.V. Diller, K.M. Dugger, K.E. Fehring, T.L. Fleming, R.P. Gerhardt, S.A. Gremel, R.J. Gutiérrez, P.J. Happe, D.R. Herter, J.M. Higley, R.B. Horn, L.L. Irwin, P.J. Loschl, J.A. Reid, and S.G. Sovern.  2004a.  Status and trends in demography of northern spotted owls, 1985-2003.  Final Report to the Interagency Regional Monitoring Program, Portland, Oregon. September 2004.  179pp.  

Anthony, R.G., R.L. Knight, G.T. Allen, B.R. McClelland, and J.I. Hodges.  1982.  Habitat use by nesting and roosting bald eagles in the Pacific Northwest.  Trans. N. Am. Wildl. Nat. Res. Conf.  47:332-342.

Anthony, R.G., S. Ackers, R. Claremont, D. Hausleitner, E. Raymond, J. Schilling, A. Smoluk, and S. Turner-Hane. 2004b. The Ecology of Northern Spotted Owls (Strix occidentalis caurina) on the Willamette National Forest, Oregon: Habitat Use and Demography. Annual Resear Report, FY 2004, Oregon Cooperative Fish and Wildlife Research Unit (OCFWRU), Department of Fisheries and Wildlife, Oregon State University, Corvallis, Oregon.

Anthony, R.G., S. Ackers, R. Claremont, J. Lavoie, D. Giessler, N. Seaman, J. Schilling, and S. Turner-Hane.  2002.  The Ecology of Northern Spotted Owls (Strix occidentalis caurina) on The Willamette National Forest, Oregon:  Habitat Use and Demography.  Annual Research Report FY 2002.  Oregon Cooperative Fish and Wildlife Research Unit, Department of Fisheries and Wildlife, Oregon State University, Corvallis, OR.

Awbrey, F.T., and A.E. Bowles. 1990. The effects of aircraft noise and sonic booms on raptors: a preliminary model and a synthesis on the literature on disturbance. U.S. Air Force, Patterson Air Force Base, Ohio.

Barrowclough, G. F. and R. J. Gutiérrez. 1990.  Genetic variation and differentiation in the spotted owl.  Auk 107:737-744.

Barrowclough, G.F., R.J. Gutiérrez, and J.G. Groth.  1999.  Phylogeography of spotted owl (Strix occidentalis) populations based on mitochondrial DNA sequences; gene flow, genetic structure, and a novel biogeographic pattern.  Evolution 53(3):919-931.

Barrows, C. W., and K. Barrows.  1978.  Roost characteristics and behavioral thermoregulation in the spotted owl.  Western Birds 9:1-8.

Barrows, C.C.  1980.  Feeding ecology of the spotted owl in California.  Journal of Raptor Research 14:73-77.

Bart, J.  1995.  Amount of suitable habitat and viability of northern spotted owls.  Conservation Biology 9 (4):943-946.

Bart, J., and E.D. Forsman.  1992.  Dependence of northern spotted owls Strix occidentalis caurina on old-growth forests in the western USA.  Biological Conservation 62:95-100.

Bevis, K.R., G.M. King, and E.E. Hanson. 1997. Spotted Owls And 1994 Fires On The Yakama Indian Reservation. Pages 117-22 in J.M. Greenlee, ed. Proceedings - Fire Effects on Rare and Endangered Species Habitats Conference, Nov 13-16, 1995. Coeur D'Alene, Idaho. International Association of Wildland Fire.

Bingham, B.B., and B.R. Noon.  1997.  Mitigation of habitat “take”: Application to habitat conservation planning.  Conservation Biology 11 (1):127-138.

Blakesley, J.A., A.B. Franklin, and R.J. Gutiérrez.  1992.  Spotted owl roost and nest site selection in northwestern California.  1992.  Journal of Wildlife Management, 56(2):388-392.

Buchanan, J., E. Hanson, D. Hays, and L. Young.  1994.  An evaluation of the Washington Forest Practices Board Wildlife Committee preferred alternative for a spotted owl protection rule.  Washington Forest Practices Board Spotted Owl Scientific Advisory Group. Olympia, Washington.

Buchanan, J.B., L.L. Irwin, and E.L. McCutchen.  1995.  Within-stand nest site selection by spotted owls in the eastern Washington Cascades.  Journal of Wildlife Management 59:301-310.

Caffrey, C.  2003.  Determining impacts of West Nile Virus on crows and other birds.  American Birds (103rd Count) 57:14-21.

Caffrey, C. and C.C. Peterson.  2003.  West Nile Virus may not be a conservation issue in northeastern United States. American Birds (103rd Count) 57:14-21.

Carey, A.B.  1993.  Prey ecology and northern spotted owl diet. Abstract of presentation, Spotted Owl Symposium, annual meeting of the Raptor Research Foundation, Inc., Bellevue, Washington, November 11-15, 1992.  Journal of Raptor Research 27(1):53-54.

CDF (California Department of Forestry and Fire Protection).  2001.  California Forest Practices Rules: 2001.  Title 14, California Code of Regulations, Chapters 4, 4.5, and 10.  Sacramento, CA.

Chen, J, J.F. Franklin, and T.A. Spies. 1993. Contrasting microclimates among clearcut, edge and interior old-growth Douglas fir forest. Agric. and For. Meteorology 63:219-237.

Courtney, S.P., J.A. Blakesley, R.E. Bigley, M.L. Cody, J.P. Dumbacher, R.C. Fleischer, A.B. Franklin, J.F. Franklin, R.J. Gutiérrez, J.M. Marzluff, and L. Sztukowski.  2004.  Scientific evaluation of the status of the northern spotted owl.  Sustainable Ecosystems Institute.  Portland, Oregon.  September 2004.

Dark, S.J., R.J. Gutiérrez, and G.I. Gould.  1998.  The barred owl (Strix varia) invasion in California.  Auk 115:50-56.

Davis, R. and J. Lint.  In press. Habitat status and Trend. In Northwest forest plan—the first ten years (1994-2003): Status and trend of northern spotted owl populations and habitat.

Delaney, D.K. and T.G. Grubb.  2001.  Effects of off-highway vehicle noise on northern spotted owls: sound data results. A report to the Mendocino National Forest.A report to the Mendocino National Forest, Contract Number 43-91Z9-0-0055.

Delaney, D.K., T.G. Grubb, P. Beier, L.L Pater, and M.H. Reiser.  1999.  Effects of helicopter noise on Mexican spotted owls.  J. Wildlife Management 63(1):60-76.

Deubel, V., L. Fiette, P. Gounon, M.T. Drouet, H. Khun, M. Huerre, C. Banet, M. Malkinson, and P. Despres.  2001.  Variations in biological features of West Nile viruses. Annals of the New York Academy of Sciences 951:195-206.

Dunbar, D.L., B.P. Booth, E.D. Forsman, A.E. Hetherington, and D.J. Wilson.  1991.  Status of the spotted owl, Strix occidentalis, and barred owl, Strix varia, in southwestern British Columbia.  Canadian Field Naturalist 105:464-468.

Duncan, R.B. and R. Sidner.  1990.  Bats in spotted owl pellets in southern Arizona. Great Basin Naturalist 50:197-200.

Fitzgerald, S.D., J.S. Patterson, M. Kiupel, H.A. Simmons, S.D. Grimes, C.F. Sarver, R.M. Fulton, B.A. Fulton, B.A. Steficek, T.M. Cooley, J.P. Massey, and J.G. Sikarskie.  2003.  Clinical and pathological features of West Nile Virus infection in native North American owls (family Strigidae).  Avian Diseases 47:602-610.

Folliard, L.  1993.  Nest site characteristics of northern spotted owls in managed forest of northwest California.  M.S. Thesis.  Univ. Idaho, Moscow, ID. 

Forest Practices Board.  1996.  Permanent rules for the northern spotted owl. Washington Department of Natural Resources, Olympia, Washington.

Forsman, E.D.  1981.  Molt of the spotted owl.  Auk 98:735-742

Forsman, E.D., E.C. Meslow, and H.M. Wight.  1984.  Distribution and biology of the spotted owl in Oregon.  Wildlife Monographs 87:1-64.

Forsman, E.D., I.A. Otto, S.G. Sovern, M. Taylor, D.W. Hays, H. Allen, S.L. Roberts, and D.E. Seaman.  2001.  Spatial and temporal variation in diets of spotted owls in Washington.  Journal of Raptor Research 35(2):141-150.

Forsman, E.D., R. G. Anthony, J. A. Reid, P. J. Loschl, S. G. Sovern, M. Taylor, B. L. Biswell, A. Ellingson, E. C. Meslow, G. S. Miller, K. A. Swindle, J. A. Thrailkill, F. F. Wagner, and D. E. Seaman.  2002.  Natal and breeding dispersal of northern spotted owls.  Wildlife Monographs, No. 149.  35 pages.

Forsman, E.D., R.G. Anthony, E.C. Meslow, and C.J. Zabel.  2004.  Diets and foraging behavior of northern spotted owls in Oregon.  Journal of Raptor Research 38(3):214-230.

Forsman, E.D., S. DeStafano, M.G. Raphael, and R.G. Gutiérrez.  1996.  Demography of the northern spotted owl.  Studies in Avian Biology No. 17.  122 pp.

Franklin, A.B.  1992.  Population regulation in northern spotted owls: theoretical implications for management.  Pp 815-827 in D. R. McCullough and R. H. Barrett (eds.)., Wildlife 2001: populations.  Elsevier Applied Sciences, London, England.

Franklin, A.B., D.R. Anderson, R.J. Gutiérrez, and K.P. Burnham.  2000.  Climate, habitat quality, and fitness in northern spotted owl populations in northwestern California.  Ecological Monographs, 70(4): 539-590.

Franklin, A.B., K.P. Burnham, G.C. White, R.J. Anthony, E.D. Forsman, C. Sanchez, J.D. Nicols and J. Hines.  1999.  Range-wide status and trends in northern spotted owl populations. Colorado Coop. Fish and Wildl. Res. Unit, Fort Collins, Colorado and Oregon Coop. Fish and Wildl. Res. Unit, Corvallis, OR.  Unpublished report.

Gaines, W.L., R.A. Strand, and S.D. Piper.  1997.  Effects of the Hatchery Complex Fires on northern spotted owls in the eastern Washington Cascades. Pages 123-129 in Dr. J.M. Greenlee, ed. Proceedings of the First Conference on Fire Effects on Rare and Endangered Species and Habitats, November 13-16, 1995. International Association of Wildland Fire. Coeur d’Alene, ID.

Ganey, J.L.  1992.  Food habits of Mexican spotted owls in Arizona.  Wilson Bulletin 104(2):321-326.

Ganey, J.L., W.M. Block, J.K. Dwyer, B.E. Strohmeyer, and J.S. Jenness.  1998.  Dispersal movements and survival rates of juvenile Mexican spotted owls in northern Arizona.  Wilson Bulletin 110:206-217.

Garmendia, A.E., H.J. Van Kruiningen, R.A. French, J.F. Anderson, T.G. Andreadis, A. Kumar, and A.B. West.  2000.  Recovery and identification of West Nile virus from a hawk in winter.  Journal of Clinical Microbiology 38:3110-3111.

Goheen, E.M., E.M. Hansen, A. Kanaskie, M.G. Williams, N. Oserbauer, and W. Sutton.  2002.  Sudden oak death caused by Phytophthora ramorum in Oregon.  Plant Disease 86:441.

Gremel, S.  2000.  Spotted owl monitoring in Olympic National Park: 2000 annual report.  U.S. Department of the Interior, National Park Service, Olympic National Park, Port Angeles, Washington.

Gremel, S.  2003.  Spotted owl monitoring in Olympic National Park: 2003 annual report.  U.S. Department of the Interior, National Park Service, Olympic National Park, Port Angeles, Washington.

Grubb, T.G. and R.M. King.  1991.  Assessing human disturbance of breeding bald eagles with classification tree models.  Journal of Wildlife Management 55:501-512.

Gutierrez, R. J., A. B. Franklin, and W. S. LaHaye. 1995.  Spotted Owl (Strix occidentalis).  In The Birds of North America, no. 179. (A. Poole and E Gill, Eds.).  Academy of Natural Sciences, Philadelphia, and American Ornithologists' Union, Washington, D.C.

Gutiérrez, R.J.  1994.  Changes in the distribution and abundance of spotted owls during the past century.  Studies in Avian Biology 15:293-300.

Gutiérrez, R.J.  1996.  Biology and distribution of the northern spotted owl.  Pages 2-5 in E.D. Forsman, S. DeStefano, M.G. Raphael, and R.J. Guiterrez (Eds): Studies in Avian Biology No. 17.

Haig, S.M., R.S. Wagner, E.D. Forsman, and T.D. Mullins.  2001.  Geographic variation and genetic structure in spotted owls.  Conservation Genetics 2(1): 25-40.

Haig, S.M., T.D. Mullins, E.D. Forsman, P. Trail, and L. Wennerberg.  In Press.  Genetic identification of Spotted Owls, Barred Owls, and their hybrids: evolutionary and legal implications.  Conservation Biology.

Hamer, T. E.  1988.  Home range size of the northern barred owl and northern spotted owl in western Washington.  M.S. Thesis.  Western Washington University, Bellingham, WA.

Hamer, T. E., E. D. Forsman, A. D. Fuchs, and M. L. Walters.  1994.  Hybridization between barred and spotted owls.  Auk 111(2):487-492.

Hamer, T.E., D.L. Hays, C.M. Senger, and E.D. Forsman.  2001.  Diets of northern barred owls and northern spotted owls in an area of sympatry.  Journal of Raptor Research 35(3):221-227.

Hamer, T.E., S.G. Seim, and K.R. Dixon.  1989.  Northern spotted owl and northern barred owl habitat use and home range size in Washington: preliminary report. Washington Department of Wildlife, Olympia, Washington.

Hanson, E., D. Hays, L. Hicks, L. Young. and J. Buchanan.  1993.  Spotted Owl Habitat in Washington: A Report to the Washington Forest Practices Board.   Washington Forest Practices Board,  Spotted owl Advisory Group.  Final Report: December 20, 1993.  Olympia, Washington.  116 pages.

Harestad, A., J. Hobbs, and I. Blackburn.  2004.  Précis of the Northern Spotted Owl in British Columbia.  Pages. 12-14 in Zimmerman, K., K. Welstead, E. Williams, J. Turner, (editors).  Northern Spotted Owl Workshop Proceedings.  Forrex Series (online No. 14), Vancouver, British Columbia, Canada.

Henke, A.L., T.Y. Chi, J. Smith, C. Brinegar.  Unpublished Draft.  Microsatellite Analysis of Northern and California Spotted Owls in California. Conservation Genetics Laboratory, Department of Biological Sciences, San Jose State University, San Jose, California.

Hershey, K.T., E.C. Meslow, and F.L. Ramsey.  1998.  Characteristics of forests at spotted owl nest sites in the Pacific Northwest.  Journal of Wildlife Management 62(4):1398-1410.

Herter, D.R., and L.L. Hicks.  2000.  Barred owl and spotted owl populations and habitat in the central Cascade Range of Washington.  Journal of Raptor Research 34(4): 279-286.

Herter, D.R., L.L. Hicks, H.C. Stabins, J.J. Millspaugh, A.J. Stabins, and L.D. Melampy.  2002. Roost site characteristics of northern spotted owls in the nonbreeding season in central Washington. Forest Science 48(2):437-446.

Irwin, L.L., D.F. Rock, and G.P. Miller.  2000.  Stand structures used by northern spotted owls in managed forests. J. Raptor Res. 34(3):175-186.

Isaacs, F. and B. Anthony.  2004.  Oregon State University.  Results of the 2004 bald eagle nest survey.  Unpublished literature.

Iverson, W.F.  1993.  Is the barred owl displacing the spotted owl in western Washington?  M.S. Thesis, Western Washington University, Bellingham, Washington.

Iverson, W.F.  2004.  Reproductive success of Spotted Owls sympatric with Barred Owls in western Washington.  Journal of Raptor Research 38(1):88-91.

Johnson, D.H.  1992.  Spotted owls, great horned owls, and forest fragmentation in the central Oregon Cascades.  M.S. Thesis, Oregon State University, Corvallis, OR.

Johnston, A.  2002.  Northern spotted owl survey and monitor report.  U.S. Department of Interior, National Park Service, Crater Lake National Park, Crater Lake, Oregon.

Kelly, E.G.  2001.  Range expansion of the northern barred owl: an evaluation of the impact on spotted owls.  M.S. Thesis, Oregon State University, Corvallis, Oregon.

Kelly, E.G. and E.D. Forsman.  2004.  Recent records of hybridization between barred owls (Strix varia) and northern spotted owls (S. occidentalis caurina).  Auk 121:806-810.

Kerns, S.J., and D. Allwardt.  1992.  Proximity of hiuman activitity to northern spotted owl nesting pairs on lands of the Pacific Lumber Company.  Unpublished document. 15 pages.

King, G.M., K.R. Bevis, M.A. Rowe, E.E. Hanson.  1997.  Spotted owls use of habitat impacted by 1994 fires on the Yakama Indian Reservation: three years post fire.

Komar, N., N.A. Panella, J.E. Burns, S.W. Dusza, T.M. Mascarenhas, and T.O. Talbot.  2001.  Serologic evidence for West Nile virus infection in birds in the New York City vicinity during an outbreak in 1999.  Emerging Infectious Diseases 7(4):621-5.

Kuntz II, R.C. and R.G. Christophersen.  1996.  A survey of the northern spotted owl in North Cascades National Park Service Complex.  NPS Technical Report NPS/CCSONOCA/NRTR-96/05. U.S. Department of the Interior, National Park Service, North Cascades National Park, Sedro Woolley, Washington.

Lahaye, W.S., and R.J. Gutierrez.  1999.  Nest sites and nesting habitat of the northern spotted owl in northwestern California.  Condor 101:324-330.                    

Lahaye, W.S., R.J. Guiterrez, and J.R. Dunk.  2001.  Natal dispersion of the spotted owl in southern California: dispersal profile of an insular population.  Condor 103:691-700. 

Laidig, K.J., and D.S. Dobkin.  1995.  Spatial overlap and habitat association of Barred Owls and Great Horned Owls in southern New Jersey.  Journal of Raptor Research 29:151–157.

Laymon, S. A.  1991.  Diurnal foraging by spotted owls.  Wilson Bulletin 103: 138-140.

Laymon, S.A.  1988.  The ecology of the spotted owl in the central Sierra Nevada, California. Ph.D. Dissertation, University of California, Berkeley, California.Laymon, S.A. 1991. Diurnal foraging by spotted owls. Wilson Bulletin 103(1):138-140.

Leskiw, T., and R.J. Gutiérrez.  1998.  Possible predation of a Spotted Owl by a Barred Owl.  Western Birds 29:225–226.

Lint, J. (tech. coord.).  2005.  Northwest Forest Plan—the first 10 years (1994–2003): status and trends of northern spotted owl populations andhabitat.  Gen. Tech. Rep. PNW-GTR-648.  Portland, OR:  U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station.  176 pages.

Livezey, K.B.  In review. Iverson (2004) on spotted owls and barred owls: comments on methods and conclusions. Journal of Raptor Research.

Marra, P.P., S. Griffing, C. Caffrey, A.M. Kilpatrick, R. McLean, C. Brand, E. Saito, A.P. Dupuis, L. Kramer, and R. Novak.  2004.  West Nile Virus and wildlife. BioScience 54(5):393-402.

Marzluff, J.M., and M. Restani. 1999. The effects of forest fragmentation on rates of avian nest predation and parasitism. College of Forest Resources, Univ. of Washington, Seattle. Unpublished report.

McLean, R.G., S.R. Ubico, S.E. Docherty, W.R. Hansen, L. Sileo, and T.S. McNamara.  2001.  West Nile Virus and transmission and ecology in birds.  Annals of the New York Academy of Sciences 951:54-57.

Meyer, J.S., L.L. Irwin, and M.S. Boyce.  1998.  Influence of habitat abundance and fragmentation on northern spotted owls in western Oregon.  Wildlife Monographs 139: 1-51.

Miller, G.S.  1989.  Dispersal of juvenile spotted owls in western Oregon.  M.S. Thesis.  Oregon State University, Corvallis, Oregon.

Miller, G.S., R.J. Small, and E.C. Meslow.  1997.  Habitat selection by spotted owls during natal dispersal in western Oregon.  J. Wildl. Manage.  61(1):140-150.

Moen, C.A., A.B. Franklin, and R.J. Gutiérrez.  1991.  Age determination of subadult northern spotted owls in northwest California.  Wildlife Society Bulletin 19:489-493           

North, M.P., G.Steger, R.Denton, G.Eberlein, T. Munton, and K. Johnson.  2000.  Association of weather and nest-site structure with reproductive success in California spotted owls.  Journal of Wildlife Management 64(3):797-807.

O’Halloran, K.  1989.  Spotted owl inventorying and monitoring:  annual report for USDA Forest Service, Pacific Northwest Region, Portland, OR.

Olson, G.S., E. Glenn, R.G. Anthony, E.D. Forsman, J.A. Reid, P.J. Loschl, and W.J. Ripple. 2004.   Modeling demographic performance of northern spotted owls relative to forest habitat in Oregon.  Journal of Wildlife Management.

ODF (Oregon Department of Forestry).  2000.  Forest Practices Administrative Rules and Forest Practices Act.  Salem, OR.

Pearson, R.R., and K.B. Livezey.  2003.  Distribution, numbers, and site characteristics of spotted owls and barred owls in the Cascade Mountains of Washington.  Journal of Raptor Research 37(4):265-276.

Perkins, J.P. 2000. Land cover at northern spotted owl nest and non-nest sites, eastcentral coast ranges, Oregon. M.S. thesis. Department of Forest Resources, Oregon State University, Corvallis, OR.

Platt, J.B.  1977.  The breeding behavior of wild and captive gyrfalcons in relation to their environment and human disturbance.  Dissertation.  Cornell Univ., Ithaca, New York, USA.

Rizzo, D.M., M. Garbeloto, J.M. Davidson, G.W. Slaughter, and S.T. Koike.  2002.  Phytophthora ramorum as the cause of extensive mortality of Quercus spp. and Lithocarpus densiflorus in California.  Plant Disease 86:205-214.

Rosenberg, D.K., K.A. Swindle, and R.G. Anthony.  2003.  Influence of prey abundance on northern spotted owl reproductive success in western Oregon.  Canadian Journal of Zoology 81:1715-1725.

Schmidt, K.  2003.  Northern spotted owl monitoring and inventory, Redwood National and State Parks, 2002 annual report.  Redwood National and State Parks, Orick, California.

Simon-Jackson, T.  1989.  Spotted owl inventory and monitoring program:  annual report for 1989.  USDA Forest Service, Pacific Southwest Region, San Francisco, CA.

Sisco, C.L.  1990.  Seasonal home range and habitat ecology of spotted owls in northwestern California.  M.S. Thesis.  Humboldt State University, Arcata, California.

Solis, D.M., and R.J. Gutiérrez.  1990.  Summer habitat ecology of northern spotted owls in northwestern California.  The Condor 92:739-748.

Sovern, S.G., E.D. Forsman, B.L. Biswell, D.N. Rolph, and M. Taylor.  1994.  Diurnal behavior of the spotted owl in Washington.  Condor 96(1):200-202.

Swarthout, E.C.H. and R.J. Steidl. 2001. Flush responses of Mexican spotted owls to recreationists. J. Wildlife Management 65(2):312-317.

Thomas, J.W., and M.G. Raphael (Eds.).  1993.  Forest Ecosystem Management: An Ecological, Economic, and Social Assessment.  Report of the Forest Ecosystem Management Assessment Team (FEMAT).  July 1993. Portland, OR: USDA Forest Service and the USDI Bureau of Land Management.

Thomas, J.W., E.D. Forsman, J.B. Lint, E.C. Meslow, B.R. Noon, and J. Verner.  1990.  A conservation strategy for the northern spotted owl.  Report of the Interagency Scientific Committee to address the conservation of the northern spotted owl.  Unpublished interagency document.  458 pages.

Thomas, J.W., M.G. Raphael, R.G. Anthony, E.D. Forsman, A.G. Gunderson, R.S. Holthausen, B.G. Marcot, G.H. Reeves, J.R. Sedell, and D.M. Solis.  1993.  Viability assessments and management considerations for species associated with late-successional and old-growth forests of the Pacific Northwest.  USDA Forest Service, Portland, Oregon.

Turner, S.  1999.  Letter on fledge data from the Central Cascades Study area. To Kit Hershey, U.S. Fish and Wildlife Service, Portland, Oregon.

USDA Forest Service and USDI Bureau of Land Management.  1994a.  Record of decision for amendments to Forest Service and Bureau of Land Management planning documents within the range of the northern spotted owl; standards and guidelines for management of habitat for late-successional and old-growth forest related species within the range of the northern spotted owl.  Portland, Oregon.         

USDA Forest Service and USDI Bureau of Land Management.  1994b.   Final supplemental environmental impact statement on management of habitat for late-successional and old-growth forest related species within the range of the northern spotted owl.  Portland, Oregon.  2 vols. and appendices.

USFWS (U.S. Fish and Wildlife Service).  1986.  Recovery plan for the Pacific Bald Eagle. U.S. Fish and Wildl. Serv., Portland, OR.

USFWS (U.S. Fish and Wildlife Service).  1987.  The northern spotted owl status review.  U.S. Fish and Wildlife Service, Portland, OR.

USFWS (U.S. Fish and Wildlife Service).  1989.  The Northern Spotted Owl; a status review supplement.  Fish and Wildlife Service.  Portland, Oregon.  113 pp.

USFWS (U.S. Fish and Wildlife Service).  1990a. 1990 status review:  northern spotted owl; Strix occidentalis caurina.  Report to the U.S. Fish and Wildlife Service, Portland, OR.

USFWS (U.S. Fish and Wildlife Service).  1990b.  Endangered and threatened wildlife and plants; determination of threatened status for the northern spotted owl; final rule.  Federal Register, 50 CFR 17: 26,114-26,194.

USFWS (U.S. Fish and Wildlife Service).  1992a.  Endangered and Threatened Wildlife and Plants; determination of critical habitat for the northern spotted owl.  Federal Register 57: 1796-1838.

USFWS (U.S. Fish and Wildlife Service).  1992b.  Endangered and Threatened Wildlife and Plants; Draft Recovery Plan for the northern spotted owl. 

USFWS (U.S. Fish and Wildlife Service).  1994.  Final biological opinion for the preferred alternative of the Supplemental Environmental Impact Statement on Management of Habitat for Late-Successional and Old-Growth Forest Related Species Within the Range of the Northern Spotted Owl. Portland, Oregon, USA.

USFWS (U.S. Fish and Wildlife Service).  1995.  Endangered and threatened wildlife and plants; bald eagle reclassification; final rule.  Fish and Wildlife Service, Federal Register Notice: 36,000-36,010.

USFWS (U.S. Fish and Wildlife Service).  1999.  Endangered and threatened wildlife and plants; proposed rule to remove the Bald Eagle in the lower 48 states from the list of endangered and threatened wildlife.  Fed. Register 64:36453-36464.

USFWS (U.S. Fish and Wildlife Service).  2001.  A range wide baseline summary and evaluation of data collected through section 7 consultation for the northern spotted owl and its critical habitat: 1994-2001.  Portland, OR.  Unpublished document.  41 pages.

USFWS (U.S. Fish and Wildlife Service).  2003.  Estimates of distances at which incidental take of murrelets and spotted owls due to harassment are anticipated from sound-generating, forest-management activities in Olympia National Forest.  Lacey, WA.

USFWS (U.S. Fish and Wildlife Service).  2004.  Northern Spotted Owl Five Year Review: Summary and Evaluation, Portland, OR.  72pp.

USFWS (U.S. Fish and Wildlife Service).  2005a.  Northwest Forest Plan & Section 7 consultation effects tracker.  Region 1 internal website, Portland, OR

USFWS (U.S. Fish and Wildlife Service).  2005b.  Draft: Disturbance and Disruption Distances for Northern Spotted Owls.  Portland, OR.

USFWS (U.S. Fish and Wildlife Service).  2006.  Northwest Forest Plan & Section 7 consultation effects tracker.  Region 1 internal website, Portland, OR

USFWS, (U.S. Fish and Wildlife Service) and NMFS (National Marine Fisheries Service).  1998.  Procedures for Conducting Consultation and Conference Activities under Section 7 of the Endangered Species Act. 

Verner, J., R.J. Gutiérrez, and G.I. Gould, Jr.  1992.  The California spotted owl: general biology and ecological relations. Pages 55-77 in Verner, J., K.S. McKelvey, B.R. Noon, R.J. Gutiérrez, G.I. Gould, Jr., and T.W. Beck (technical coordinators). The California Spotted Owl: A Technical Assessment of Its Current Status. PSW-GTR-133, USDA Forest Service, Pacific Southwest Research Station, Albany, California.

Ward, J. W. Jr.  1990.  Spotted owl reproduction, diet and prey abundance in northwest California.  M.S. Thesis.  Humboldt State University, Arcata.      

Ward, J. W. Jr., R.J. Gutiérrez, and B.R. Noon.  1998.  Habitat selection by northern spotted owls: the consequences of prey selection and distribution.  Condor 100:79-92.Weathers, W.W., P.J. Hodumand, and J.A. Blakesley.  2001.  Thermal ecology and ecological energetics of California spotted owls.  The Condor 103:678-690.

Ward, J.P., Jr. and W.M. Block.  1995.  Mexican Spotted Owl prey ecology. Pages 1-48 in USDI Fish and Wildl. Serv., Recovery plan for the Mexican Spotted Owl Vol. 2 USDI Fish and Wildl. Serv., Albuquerque, New Mexico.

Weathers, W.W., Hodum, P.J., and J.A. Blakesley.  2001.  Thermal ecology and ecological energetics of California spotted owls.  The Condor 103: 678-690.

Weidemeier, D.J. and S.P. Horton.  2000.  Trends in spotted owl and barred owl detections in the Olympic Experimental State Forest from 1991 to 1999.  (Paper file reads:  Detection rates and occupancy trends of spotted and barred owls in the Olympic Experimental State Forest).  Northwestern Naturalist 81(3):63.

Wesemann and Rowe.  1987.  Factors influencing the distribution and abundance of burrowing owls in Cape Coral, Florida.  In Integrating man and nature in the metropolitan environment.  Proceedings of the national symposium on urban wildlife, eds., L.W. Adams and D.L. Leedy, 129-137.  National Institute for Urban Wildlife, Columbia, Maryland, USA.

Zabel C.J., S.E. Salmons, and M. Brown.  1996.  Demography of northern spotted owls in southwestern Oregon.  Studies in Avian Biology 17:77-82.

Zabel, C. J., J.R. Dunk, H.B. Stauffer, L.M. Roberts, B.S. Mulder, and A. Wright.  2003.  Northern spotted owl habitat models for research and management application in California (USA).  Ecological Applications 13(4): 1027-1040.

Zabel, C. J., K.M. McKelvey, and J.P. Ward, Jr.  1995.  Influence of primary prey on home-range size and habitat-use patterns of northern spotted owls (Strix occidentalis caurina).  Canadian Journal of Zoology 7.

 



[1] Affects to fish are evaluated through the Aquatic Level 1 Team, which have consulted on many of these projects under a separate biological opinion (1-7-03-F-20).  The remainder of the projects either have no effects to listed fish or will be consulted on in a separate biological opinion.

[2] Physiographic provinces were established by the Northwest Forest Plan (USDA and USDI 1994a)

[3]  Data compiled by the U.S. Fish and Wildlife Service, Northern Spotted Owl Coordination Group.

 

[4] Data compiled by the U.S. Fish and Wildlife Service, Northern Spotted Owl Coordination Group.

[5] The critical breeding period for the Oregon Western Cascades Physiographic Province is applied to the entire action area.  Even though a portion of the action area is within the Oregon Eastern Cascades Physiographic Province, a lack of data to calculate a critical nesting period for this area has caused the Service to use the breeding data from the Western Cascades as a surrogate.

[6] Estimate of suitable spotted owl habitat within disruption distances of the proposed action provided by Salem BLM, Eugene BLM, Mt. Hood NF, Willamette NF and the Columbia River Gorge National Scenic Area.