Biological Opinion

for Effects to Northern Spotted Owls (Strix occidentalis caurina)

and Northern Spotted Owl Critical Habitat

from the 2007 Plantation Thin

that have the potential to adversely affect, due to habitat modification and disturbance,

on Mt. Hood National Forest,

Clackamas Ranger District

(FWS Reference Number 1-7-06-F-0216)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

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. 4

LIST OF FIGURES. 4

INTRODUCTION.. 5

CONSULTATION HISTORY.. 5

BIOLOGICAL OPINION.. 6

1.0 Description of the Proposed Action.. 6

1.1 Definitions. 14

1.1.1 Spotted Owl 14

1.1.2 Disturbance/Disruption distances. 14

1.1.3 Habitat Modification. 14

1.2 Management Standards. 15

1.3 Action Area. 16

2.0 Status of the NORTHERN SPOTTED OWL. 17

2.1 Legal Status. 17

2.2 Life History. 17

2.2.1 Taxonomy. 17

2.2.2 Physical Description. 17

2.2.3 Current and Historical Range. 17

2.2.4 Behavior 18

2.2.5 Habitat Relationships. 18

2.2.6 Reproductive Biology. 20

2.2.7 Dispersal Biology. 20

2.2.8 Food Habits. 21

2.2.9 Population Dynamics. 22

2.3 Threats. 22

2.3.1 Reasons for Listing. 22

2.3.2 New Threats. 23

2.4 Conservation Needs of the Spotted Owl 28

2.4.1 Habitat-specific Needs. 28

2.4.2 Habitat-independent Needs. 29

2.4.3 Conservation Strategy. 29

2.4.4 Federal Contribution to Recovery. 29

2.4.5 Conservation Efforts on Non-Federal Lands. 30

2.5 Current Condition of the Spotted Owl 31

2.5.1 Range-wide Habitat and Population Trends. 31

3.0 Status of Northern Spotted Owl Critical Habitat. 41

3.1 Legal Status. 41

3.2 Primary Constituent Elements. 41

3.3 Conservation Role of Critical Habitat 41

3.4 Current Condition of Critical Habitat 42

3.4.1 Range-wide. 42

3.4.2 Provinces with the Majority of Impacts Range-wide or to Their Baseline. 43

3.4.3 Summary. 44

4.0 Analysis of Species/Critical Habitat. 46

4.1 Concurrence for Spotted Owl 46

4.2 Spotted Owl Critical Habitat 47

5.0 Environmental Baseline. 47

5.1 Spotted Owl Critical Habitat 47

5.1.1 OR-10. 48

5.1.2 OR-12. 49

5.1.3 Physiographic Province. 49

6.0 Effects of the Action.. 49

6.1 Spotted Owl Critical Habitat 49

7.0 Effects of the Action BY ACTIVITY TYPE. 51

7.1 Heavy Thinning. 51

7.1.1 Spotted Owl Critical Habitat 51

7.2 Light to Moderate Thinning. 52

7.2.1 Spotted Owl Critical Habitat 52

7.3 Instream Habitat Restoration. 52

7.3.1 Spotted Owl Critical Habitat 52

7.4 Summary of Effects. 52

7.4.1 Spotted Owl Critical Habitat 52

8.0 COMBINED Effects to Critical habitat. 53

8.1 Critical Habitat Unit OR-10. 53

8.2 Critical Habitat Unit OR-12. 53

8.3 Fragmentation between Critical Habitat Units. 54

8.4 Oregon Western Cascades Physiographic Province. 54

8.5 Range-wide. 54

9.0 Cumulative Effects. 54

10.0 Conclusion.. 55

11.0 Amount or Extent of Take. 55

12.0 Reasonable and Prudent Measures. 55

13.0 Terms and Conditions. 56

14.0 Conservation Recommendations. 56

15.0 Reinitiation Notice. 56

LITERATURE CITED.. 57

 

 


LIST OF TABLES

Table 1.  Description of activities within the Mt. Hood National Forest, 2007 Plantation Thin. 9

Table 2.  Mt. Hood National Forest, 2007 Plantation Thin projects that have the potential to affect spotted owl habitat. 11

Table 3.  Mt. Hood National Forest, 2007 Plantation Thin effects to northern spotted owl habitat by activity type. 12

Table 4.  Mt. Hood National Forest, 2007 Plantation Thin effects to northern spotted owl habitat by land use allocation. 13

Table 5.  Mt. Hood National Forest, 2007 Plantation Thin effects to northern spotted owl critical habitat (OR-10 and OR-12) by land use allocation. 13

Table 6.  Disturbance/disruption distances for northern spotted owls during the breeding period (March 1 – September 30). 15

Table 7.  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 August 8, 2006. 36

Table 8.  Changes to suitable1 habitat acres from activities subject to section 7 consultations and other causes range-wide from 1994 to April 2004. 37

Table 9.  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). 38

Table 10.  Change in suitable spotted owl habitat (acres) from 1994 to April 12, 2004, resulting from Federal management actions (Mgmt) and natural events by physiographic province. 39

Table 11.  Aggregate results of all adjusted, suitable critical habitat 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 August 31, 2006. 45

Table 12.  Summary of effects calls to northern spotted owls, 2007 Plantation Thin, Mt. Hood NF. 46

Table 13.  Current status of spotted owl Critical Habitat Units by Northwest Forest Plan allocation and by Unit. 47

Table 14.  Designated functions of Critical Habitat Units (CHU) occurring within the action area. 48

Table 15.  Effects of the proposed action on spotted owl critical habitat, 2007 Plantation Thin, Mt. Hood NF. 50

Table 16.  Summary of effects determinations to spotted owl critical habitat from habitat modification performed in compliance with the Management Standards in Section 1.2. 51

Table 17.  2007 Plantation Thin proposed treatments as related to specific critical habitat units for the northern spotted owl. 53

 

LIST OF FIGURES

Figure 1.  Physiographic provinces, northern spotted owl demographic study areas, and demographic trends (Anthony et al. 2004). 40

 


INTRODUCTION

 

This document transmits the U.S. Fish and Wildlife Service’s (Service) Biological Opinion (BO) based on our review of the 2007 Plantation Thin activities described below that are proposed for implementation by the Mt. Hood National Forest, Clackamas River Ranger District and their effects on the northern spotted owl (Strix occidentalis caurina) (spotted owl), and spotted owl critical habitat in accordance with section 7 of the Endangered Species Act (Act) of 1973, as amended (16 U.S.C. 1531 et seq.).  Your July 24, 2006 request for formal and informal consultation was received on July 26, 2006.

 

This BO is based on the following major sources of information: the Forest Services’ (FS), July 7, 2006, 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. 2004); 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.  The NWFP boundaries were delineated based on 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.

 

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 Mt. Hood National Forest Land and 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 BO. 

 

The Willamette Province Terrestrial Level 1 Team (Team) was presented with a draft of this project[1] for review at the April 13, 2006 Team meeting.  Final edits and team concurrence occurred at the July 13, 2006 Level 1 meeting.  After the completion of edits and signature, the BA was received by the Fish and Wildlife Service on July 26, 2006.  A follow up phone conversation with Sharon Hernandez (contact person for this BA, at the Mt. Hood National Forest), clarified that large helicopter work in the late breeding season would not occur within the disruption distance, 120 yards, on any spotted owl activity center. 

 

Formal consultation was officially initiated by this office on July 26, 2006, upon receipt of the final BA. 

 

BIOLOGICAL OPINION

 

This BO does not rely on the regulatory definition of “destruction or adverse modification” of critical habitat at 50 CFR 402.02.  Instead, we have relied upon the statutory provisions of the Act to complete the following analysis with respect to critical habitat.

 

1.0 Description of the Proposed Action

 

The FS propose the 2007 Plantation Thin within the Clackamas Ranger District of the Mt Hood National Forest.  This project can be grouped into seven routine activity types (Table 1).  A description of these activity types is presented in the BA and Table 1.  Additionally, a break down of the projects is provided by activity type (Table 2, Table 3), spotted owl habitat affected (Table 4) and critical habitat affected (Table 5).

 

The timber sales would thin and harvest wood fiber in up to 6,610 acres (2,880 acres of matrix, 1,870 acres of the dry portion of riparian reserves, and 1,860 acres in a late-successional reserve (LSR)).  All the areas treated would be young stands 60 years old or less.  The silvicultural prescription will be developed that includes a variable density thinning designed to maintain diversity currently present in the stands.    

 

Thinning would generally remove the smaller trees in the matrix and would remove trees from all levels of the canopy in the LSRs.  Diversity and variability would be maintained in several ways.  This list is a summary of practices that will be included in the design criteria.

 

o       Leave tree spacing would vary with relative densities ranging from 25 to 35 in the matrix and 20 to 30 in riparian reserves and 20 to 40 in LSRs.

o       Leave trees would include minor species in all land allocations.

o       Skips and gaps would be created.  Larger skips and gaps would be created in the LSRs, while smaller skips and gaps would be created in the matrix portions of the project area (See below). 

o       Leave trees would include trees with the elements of wood decay in all land allocations.

o       Leave trees would include some live trees where their crowns touch certain key snags.  A higher level of protection would occur within the LSRs. 

o       All non-hazardous snags would be retained in all land allocations.

o       All existing down logs would be retained and key concentrations of woody debris in the older decay classes would be protected.  Increased protection would occur within the LSRs. 

o       Snags and down logs would be created.  A higher level of course woody debris would be managed for within the LSRs (See below).

 

          

Management of Riparian Reserve-Matrix Lands -   For this project, riparian reserve widths are 180 feet for non-fish-bearing streams and 360 feet for fish-bearing streams.  The design criteria will include no-harvest buffers of approximately 30 to 100 feet on each side of streams.  Seeps and wet areas would be excluded from harvest.  Within the units outside of this no-harvest buffer proposed for riparian reserve thinning, the prescription would be adjusted to create conditions suitable for accelerated diameter growth and enhance the potential for large wood recruitment.  The intention is to enhance riparian reserves by accelerating the development of mature and late-successional stand conditions.  Wider spacing would also mean that one thinning entry would create the desired conditions (compared to the matrix thinning spacing where multiple thinning entries would likely occur).  Riparian thinning would generally remove the smaller trees, leaving a relative density (RD) of 20 to 30, which is approximately 50 to 105 trees per acre. 

 

Management of LSRs -  On the areas proposed for late-successional reserve thinning, the prescription would be adjusted to create conditions suitable for accelerated diameter growth and enhance the potential for the development of suitable spotted owl habitat.  No stands older than 60 years would be treated in this proposed action.  The intention is to enhance the LSRs by accelerating the development of mature and late-successional stand conditions.  In some units wider spacing would also mean that one thinning entry would create the desired conditions (compared to the matrix thinning spacing where multiple thinning entries would likely occur).  In an attempt to achieve a variable density prescription not only within the units, but between units occurring within the LSR, some units would result in a denser spacing and more trees left per acre.  These units may or may not receive further entries in the future.  The LSR thinning would in places remove trees from all cohorts of the stand, in an attempt to create a multi-storied stand in the future.  A relative density of 20 to 40 would be left.  The creation of gaps and skips will be incorporated into the prescriptions in much greater frequency and size than on the matrix lands.  Skips would encompass at least 10% of the acreage being treated within the LSRs and would range in size from ¼ to 10 acres.  Gaps would be created within 3-10% of this area with no gap being larger than ¼ acres.  Post-harvest restoration projects would promote the development of snags and down woody debris to a much greater extent than they will in the matrix. 

 

Roads - New temporary roads (up to 10 miles) are needed to access the landings.  These roads would be obliterated and revegetated after completion of the project.  In addition, certain roads would need to be reconstructed, and other roads currently closed with a berm or other closure device would need to be temporarily opened during the timber harvest.  These currently closed roads would be reclosed upon the project’s completion.  The acreage of land affected by these road construction activities have been incorporated into the timber sale proposed thinning treatments (See Table 3). 

 

Fuels Treatment:  Fuels treatment would be minimal in most areas: where a mechanical harvester is used, branches would be crushed under the equipment.  Elsewhere there would be no fuels treatment except the piling and fall burning of slash and debris at landings or possibly within the units. 

 

Snag and Down Woody Debris Creation:  Post-harvest restoration projects will include snag and down woody debris creation.  Coarse woody debris would likely be created by felling trees to meet immediate down wood goals or by tree girdling to meet the goals set for the near future.  Snags would be created through various techniques such as chainsaw topping, blasting, heart-rot inoculation or other means.  Trees left in the residual stand would be in excess of stand goals to meet this need. 

 

In-stream Coarse Woody Debris Creation:  A potential post-harvest restoration project would be to create additional coarse woody debris in fish-bearing streams currently lacking this structure.  Treatment would include felling trees directly adjacent to streams targeted for coarse woody debris creation.  No trees would be selected that are potential spotted owl nest trees.  Treatment would abide by criteria determined by NMFS consultation and the Aquatic Conservation Strategy.


Table 1.  Description of activities within the Mt. Hood National Forest, 2007 Plantation Thin.

 

Description

Land Use Allocation

Heavy Thinning

Heavy thinning maintains a minimum of 30 percent and up to 40 percent average canopy closure throughout a stand (i.e., each 40-acre treatment area maintains an average canopy closure of at least 30 percent even though small areas might have a canopy closure below 30 percent).  Any treatment that would lower canopy closure to less than 30 percent is considered a regeneration harvest and is not included in this assessment.  In many cases, this treatment will have long-term benefits to spotted owls by encouraging late-successional characteristics to develop more rapidly. 

 

Heavy thinning in habitat that is not yet suitable spotted owl habitat (i.e. dispersal-only) can be for forest health or to improve the structural characteristics of a stand.  No treatment of suitable habitat is included in this assessment.

 

Heavy thinning occurring within dispersal-only habitat would “remove” the dispersal habitat and reduce it to non-habitat temporarily (i.e. capable habitat).   

 

Unit of measure is acres thinned. 

 

late-Successional Reserves, Riparian reserves and matrix

Light to Moderate Thinning

Light to moderate thinning in dispersal-only or non-habitat can be for forest health or to improve the structural characteristics of a stand.  Such thinnings maintain a minimum of 40 percent average canopy cover throughout the stand.  In many cases, this treatment will have long-term benefits to spotted owls by encouraging late-successional characteristics to occur more rapidly.  No treatment of suitable habitat is included in this assessment.

 

Light to moderate thinning occurring within dispersal-only habitat would “degrade” the habitat, but it would remain as dispersal habitat. 

 

Unit of measure is acres thinned.

late-Successional Reserves, Riparian reserves and matrix

Actions associated with the above activities, and  included within those units

Post-harvest Fuels Treatment

This includes post-harvest fuels reduction activities, including prescribed burning, jackpot burning, and mechanical treatment.  Although the majority of fuels treatment would occur on landings, some treatment could occur in the unit, potentially affecting the down wood component and residual stand.  Treatment within the Late-Successional Reserves would be minimal and would minimize any loss to the snag or coarse woody debris component.  No loss of spotted owl habitat would occur with these treatments, only a slight degrade in the remaining dispersal habitat. 

 

 Unit of measure is number of acres treated.

late-Successional Reserves, Riparian reserves and matrix

Road Construction

(This action will only be associated with Heavy Thinning)

This includes building new temporary roads needed to access proposed harvest landings.  No suitable habitat would be impacted by the construction of roads.  Only dispersal habitat could be potentially removed and re-classified as capable habitat.  All new temporary road construction would be required to be obliterated and vegetated after project completion. 

 

Unit of measure is miles of road built. 

late-Successional Reserves, dry portions of the Riparian reserves and matrix

Terrestrial Habitat Enhancement

This type of activity includes habitat enhancement in dispersal habitat for watershed health and wildlife by increasing the snag and coarse woody debris composition of the stand.  No suitable nesting trees would be treated or damaged and treatment would not occur in areas where site-specific information indicates use by nesting listed species.  Projects may include, but not limited to, the use of hand tools or chainsaws for tree-topping, bottom girdling, or placement of heartrot innoculum to create snags or wildlife trees, tree felling for coarse woody debris.  

 

Unit of measure is acres treated.

late-Successional Reserves, Riparian reserves and matirx

Post-Harvest Firewood Sales

The units could be opened to firewood gathering after harvest treatments are completed.  This could potentially affect the down woody debris component remaining in the units post-harvest.  No suitable habitat would be impacted.  There could be a slight degrade in the remaining dispersal habitat as a result of this activity

matrix

Activity associated with the above actions, but within Riparian buffers

Instream Habitat Restoration

This involves placement of coarse woody debris in some fish-bearing streams currently lack this habitat component.  Treatment would include felling trees within harvest units that are directly adjacent to streams targeted for coarse woody debris creation.  No trees would be selected that are potential spotted owl nest trees. 

 

 

Riparian Reserves and Late-Successional Reserves


Table 2.  Mt. Hood National Forest, 2007 Plantation Thin projects that have the potential to affect spotted owl habitat.

5TH Field Watershed

Proposed Treatment1, 2

Acres

Land Use Allocation

Critical Habitat Unit

Habitat Type

Degrade/ Remove

Middle Clackamas River

Light/Moderate Commerical Thin

300

200

Matrix

Matrix

OR-10

None

All Dispersal

All Degrade

Middle Clackamas River

Heavy Commerical Thin and Temporary New Road Construct3

795

450

590

675

725

745

Matrix

Matrix-RR

LSR 207

Matrix

Matrix-RR

LSR 207

OR-10

OR-10

OR-10

None

None

None

All Dispersal

All Remove

Collawash River

Light/Moderate Commercial Thin

100

150

Matrix

Matrix

OR-12

None

All Dispersal

All Degrade

 

Collawash River

Heavy Commercial Thin and Temporary New Road Construct3

270

200

390

495

510

15

Matrix

Matrix-RR

Matrix

Matrix-RR

LSR 210

LSR 210

OR-12

OR-12

None

None

None

OR-12

All Dispersal

All Remove

 

1 The post-harvest firewood sales, terrestrial habitat improvement projects and fuels treatments all occur within the unit boundaries and are not displayed in the above table.  The acres of habitat affected would be the same acres as those impacted by the commercial thin.  The additional degradation of habitat would be minimal and would not exceed what is already displayed in this table.

2 The instream treatments would occur within the stream no-harvest cut buffers of the proposed harvest units.  Due to the small amounts of second-growth trees cut and left on site within these areas, no additional impacts to spotted owls are expected.

3 The dispersal acres removed for road-construction are included within the dispersal acres removed through the commercial thin.  The number of dispersal acres removed through the road construction is very small and has similar short-term effects as the heavy thinning.

 

 


 

Table 3.  Mt. Hood National Forest, 2007 Plantation Thin effects to northern spotted owl habitat by activity type.

2007 Plantation Thin

Dispersal Habitat

Remove1

Degrade2

Acres

Acres

Heavy Thinning

5,860

 

Light/moderate Thinning

 

750

Post-Harvest Fuels Treatment

 

03

Road Construction

 

04

Terrestrial Habitat Enhancement

 

03

Post-Harvest Firewood Sales

 

03

Instream Habitat Restoration

 

05

Totals

5,860

750

1  Remove means to eliminate the functionality of this type of habitat.

2  Degrade means to affect the quality of, but not remove the functionality of this type of habitat.

3 The post-harvest firewood sales, terrestrial habitat improvement projects and fuels treatments all occur within the unit boundaries and are not displayed in the above table.  The acres of habitat affected would be the same acres as those impacted by the commercial thin.  The additional degradation of habitat would be minimal and would not exceed what is already displayed in this table.

4 The dispersal acres removed for road-construction are included within the dispersal acres removed through the commercial thin.  The number of dispersal acres removed through the road construction is very small and has similar short-term effects as the heavy thinning.

 5 The instream treatments would occur within the stream no-harvest cut buffers of the proposed harvest units.  Due to the small amounts of second-growth trees cut and left on site within these areas, no additional impacts to spotted owls are expected.

 


Table 4.  Mt. Hood National Forest, 2007 Plantation Thin effects to northern spotted owl habitat by land use allocation.

2007 Plantation Thin

Matrix

Late-Successional Reserves1

Total

Non-RR

Riparian Reserve (RR)

Acres

Acres

Acres

Acres

Dispersal Habitat

Remove2

2,130

1,870

1,860

5,860

Degrade3

750

 

 

750

Total Habitat

2,880

1,870

1,860

6,610

1    Includes associated Riparian Reserves.

2    Remove means to eliminate the functionality of this type of habitat.

3    Degrade means to affect the quality of, but not remove the functionality of this type of habitat.

 

Table 5.  Mt. Hood National Forest, 2007 Plantation Thin effects to northern spotted owl critical habitat (OR-10 and OR-12) by land use allocation.

2007 Plantation Thin

Matrix

Late-Successional Reserves1

Total

Critical habitat

Non-RR

Riparian Reserve (RR)

Acres

Acres

Acres

Acres

Dispersal Habitat

Remove2

1,065

650

605

2,320

Degrade3

400

 

 

400

Total Habitat

1,465

650

605

2,720

1    Includes associated Riparian Reserves.

2    Remove means to eliminate the functionality of this type of habitat.

3    Degrade means to affect the quality of, but not remove the functionality of this type of habitat.


1.1 Definitions

 

The seven 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 (NRF).  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.  This may alternatively be referred to as nesting, roosting, and foraging (NRF) habitat throughout this BO.

 

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

 

1.1.1.3 Dispersal habitat:  For purposes of this assessment, dispersal habitat supports owl movement across the landscape but lacks the optimal structural characteristics to support nesting.  At a minimum, dispersal habitat is comprised of conifer and mixed mature conifer-hardwood 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, and survive until they can establish a nest territory.  Juvenile owls also use dispersal habitat to move from natal areas.

 

1.1.2 Disturbance/Disruption distances

1.1.2.1 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 (Table 6).

 

1.1.2.2 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 extent to significantly impact its normal behavior (harass).  The disruption distance is a subset of the disturbance distance.

 

1.1.3 Habitat Modification

1.1.3.1 Degrade:  Means to affect the quality of spotted owl suitable or dispersal habitat without altering the functionality of such habitat.

 

Specifically, habitat degradation refers to habitat modification activities that reduce the quality of suitable or dispersal habitat while retaining the original function of that habitat, post-harvest, at the stand level.  This generally includes a reduction in canopy cover to approximately >60 percent in suitable habitat and >40 percent in dispersal habitat, when other habitat elements (including snags, downwood, tree-height class-diversity, and older hardwoods) are retained, post-harvest, at levels that provide for the original function of the stand.  The administrative unit biologist is responsible for ensuring prescriptive activities account for these structural elements and making correct effects determinations for each site specific action.

 

1.1.3.2 Remove:  Means to alter spotted owl suitable or dispersal habitat, so that the habitat no longer supports nesting, roosting, foraging, or dispersal. 


 

Table 6.  Disturbance/disruption distances for northern spotted owls during the breeding period (March 1 – September 30).


Activity

Disturbance distance

Disruption Distances when owls are actively nesting

Spotted owl breeding period
(March 1 – September 30)

Spotted owl critical breeding period
(March 1 – July 15)

Remainder of the spotted owl breeding period
(July 16 – September 30)

Use of chainsaws

440 yards (0.25 mile)

65 yards

No Disruption Anticipated

Use of heavy equipment

440 yards (0.25 mile)

35 yards

No Disruption Anticipated

Burning

440 yards (0.25 mile)

440 yards (0.25 mile)

No Disruption Anticipated

Large helicopter = Type I1, 2

880 yards (0.5 mile)

440 yards (0.25 mile)

440 yards (0.25 mile)

Type II2 - IV

440 yards (0.25 mile)

120 yards

No Disruption Anticipated

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  Kmax helicopters are considered Type I helicopters for the ICS definition but will be considered Type II for the purposes of disturbance.  Sound readings from Kmax helicopter logging on the Olympic NF registered 86 dB at 150 yards (Piper 2006).

 

1.2 Management Standards

 

The proposed action includes all processes needed to plan, evaluate, survey, prepare and complete activities including, but not limited to, falling, bucking, hauling, post-harvest burning, and firewood sales.  In addition to the descriptions and conditions in Table 1 the following standards are common to all proposed activities (i.e., any proposed activity that does not meet all of the standards in this section is not addressed by this assessment):

 

  1. A wildlife biologist shall participate in the planning and design of all activities affecting listed species.

 

  1. All proposed activities should consider the analyses for the management of federally listed species contained in pertinent watershed analyses and LSRs assessments, as amended.

 

  1. Once a year, by November 30, the Mt. Hood National Forest will complete a Project Implementation and Monitoring Form for any of these proposed actions that are likely to adversely affect a listed species or cause loss of suitable, dispersal, or critical habitat.  This form will be forwarded to the Fish and Wildlife Service.

 

  1. Except for hauling and the removal of hazard trees to protect public safety, no activity shall take place within the disruption distance of a known activity center during the March 1 to July 15th critical nesting period, unless the habitat is known to be unoccupied or there is no nesting activity, as determined by survey to protocol.  The distance and timing may be modified by the unit wildlife biologist according to site-specific information. 

 

  1. For these proposed timber harvest operations, monitoring reports must reflect the acres of treatment actually sold and awarded, or preferably completed on the ground.  Monitoring completes consultation by documenting the actual effects to the subject species.

 

  1. Monitoring will ensure that actual levels of adverse effects of impacts to critical habitat, resulting from implementation of the proposed action, do not exceed the levels anticipated by this assessment.  Before exceeding an anticipated level of incidental take or adverse effects the Mt. Hood National Forest shall inform the Interagency Level 1 Team and re-initiate formal consultation with the Fish and Wildlife Service.

 

  1. No blasting shall occur within the disruption distance of occupied or unsurveyed suitable spotted owl habitat in any land use allocation between March 1 and July 15.  The unit wildlife biologist may waive this seasonal restriction if the nest site or habitat is verified by protocol to be unoccupied.  This waiver would only be applicable for the current year. 

 

  1. No large helicopter (defined in Table 6) use within the disruption distance (vertical or horizontal) of occupied or unsurveyed suitable habitat of the spotted owl between March 1 and July 15 is 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 would only be applicable for the current year. 

 

  1. No activity that, in the opinion of the unit wildlife biologist, would remove spotted owl dispersal habitat in areas where the amount of post-activity habitat would be insufficient for owl dispersal is addressed by this assessment.

 

  1. In-stream habitat restoration projects and snag creation projects that, in the opinion of the unit biologist, remove or modify trees with potential nesting structure are not addressed by this assessment.

 

  1. No activity that would remove or downgrade northern spotted owl critical habitat in an Area of Concern is addressed by this assessment.  

 

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.”  For the purposes of this consultation, the action area is 34,682 acres and includes lands within 0.5 mile of the proposed project area.  The project area, 6,610 acres, is defined as the treatment units.  The entire action area occurs within the Clackamas River Ranger District of the Mt. Hood National Forest.

 

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 and 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. 2004).  

 

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. 2004) 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. 2004).  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. 2004).  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. 2004) 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 NWFP’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 7).  As of April 12, 2004, the Service had consulted on the proposed removal of 575,447 acres of spotted owl habitat range-wide (Table 8), of which 190,429 acres occurred on Federal lands managed under the NWFP (Table 9, Table 10).  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[2] (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 (Table 9, Table 10).  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 9).  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 9).  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 9).  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 9). 

 

Since 1994, habitat lost due to natural events was estimated at about 168,301 acres range-wide (Table 10).  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[3] 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 since 1994 about 515,000 acres of younger forests may have grown into forested stands greater than 80 years old, which may provide some of the habitat needs for the spotted owl (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 8), of which 190,429 acres occurred on Federal lands managed under the NWFP (Table 9, Table 10).  From April 12, 2004, to the present (August 8, 2006), the Service has consulted on the removal or downgrading of 15,374 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 (Table 9, Table 10) subtracted from 205,803 acres consulted on for removal through August 8, 2006 (Table 7)).  This amount of habitat loss (0.22 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 10)).  Currently, an estimated 4,862,879 acres of spotted owl habitat in Reserves receive protection under the NWFP (Table 7).

 

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. 2004).  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. 2004) (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. 2004).  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. 2004).  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. 2004).  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 7.  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 August 8, 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

7164

 1109

 30

 749

16158

156006

181216

Removed/Downgraded
(all other activities)6

 1551

0

1842

 54

478

19662

24587

Consultation Subtotal

8715

1109

1872

 803

16636

175668

205803

Removed/Downgraded
(natural disturbance)7

11556

309

2468

407

27

10553

29978

Net Changes from Land
Exchanges and Ownership Transfers

0

0

0

0

0

35

35

Other Activities Subtotal

11556

309

2468

407

27

10518

29943

Total Net Change

20271

1418

4340

1210

16663

186186

235746

BASELINE BALANCE8

3206743

27482

1634312

299009

347605

1651859

7161352

Degraded9

31861

187

3301

410

11115

439458

497452

 

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 8.  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 9.  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 1994b).

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 10.  Change in suitable spotted owl habitat (acres) 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

 

560217

91

299

390

0.07

0.11

 

WA East Cascades

 

706849

5968

5754

11722

1.66

3.27

 

WA West Cascades

 

1112480

11201

0

11201

1.01

3.12

 

Western Lowlands

 

0

0

0

0

0.00

0.00

 

OR Coast

 

516577

4544

66

4610

0.89

1.29

 

OR Klamath Mountains

 

786298

82828

117622

200450

25.49

55.88

 

OR Cascades East

 

443659

14029

4008

18037

4.07

5.03

 

OR Cascades West

 

2045763

55440

24583

80023

3.91

22.31

 

Willamette Valley

 

5658

0

0

0

0.00

0.00

 

CA Coast

 

51494

250

100

-350

0.68

0.10

 

CA Cascades

 

88237

4808

0

4808

5.45

1.34

 

CA Klamath

 

1079866

11270

15869

27139

2.51

7.57

 

TOTAL

 

7397098

190429

168301

358730

4.85

100.00

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

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. 2004).


3.0 Status of Northern Spotted Owl Critical Habitat

 

3.1 Legal Status

 

On January 15, 1992, the Service designated critical habitat for the spotted owl within 190 CHUs which encompass nearly 6.9 million acres of Federal lands across Washington (2.2 million acres), Oregon (3.3 million acres), and California (1.4 million acres) (USFWS 1992b).  The spotted owl critical habitat final rule states: "Section 7 analysis of activities affecting owl critical habitat should consider provinces, subprovinces, and individual CHUs, as well as the entire range of the subspecies (page 1823).”  The rule goes on to assert the basis for an adverse modification opinion should be evaluated at the provincial scale (page 1823).

 

The final rule designating critical habitat made it clear (FR pages 1820-1825) that timber harvest was expected in critical habitat.  It says that the Service anticipates using the Interagency Scientific Committee (ISC) Plan, which is now the NWFP, “as a basis for determining the level of allowable harvest or other activities that affect owl habitat within critical habitat.”  It also expected that the Recovery Plan or other conservation plan for owls (e.g. NWFP) would make recommendations for managing owl habitat, including owl habitat within critical habitat.

 

3.2 Primary Constituent Elements

 

Primary constituent elements (PCEs) are the physical and biological features of critical habitat essential to a species' conservation.  PCEs identified in the spotted owl critical habitat final rule include those physical and biological features that support nesting, roosting, foraging, and dispersal (USFWS 1992b).  Features that support nesting and roosting habitat typically include a moderate to high canopy (60 to 90 percent); a multi-layered, multi-species canopy with large [> 30 inches diameter at breast height] overstory trees; a high incidence of large trees with various deformities (e.g., large cavities, broken tops, mistletoe infections, and other evidence of decadence); large snags; large accumulations of fallen trees and other woody debris on the ground; and sufficient open space below the canopy for owls to fly (Thomas et al. 1990).  Foraging habitat generally consists of attributes similar to those in nesting and roosting habitat, but may not always support successfully nesting pairs (USFWS 1992b).  Dispersal habitat, at minimum, consists of stands with adequate tree size and canopy closure to provide protection from avian predators and at least minimal foraging opportunities: there may be variations over the owl’s range (e.g., drier sites in the east Cascades or northern California) (USFWS 1992b).

 

3.3 Conservation Role of Critical Habitat

 

Spotted owl critical habitat was designated based on the identification of large blocks of suitable habitat that are well distributed across the range of the spotted owl.  Critical habitat units were intended to identify a network of habitats that provided the functions considered important to maintaining stable, self-sustaining, and interconnected populations over the range of the spotted owl, with each CHU having a local, provincial, and a range-wide role in spotted owl conservation.  Most CHUs were expected to provide suitable habitat for population support, some were designated primarily for connectivity, and others were designated to provide for both population support and connectivity.

 

The NWFP was developed using conservation principles similar to those used to designate critical habitat and is considered the range-wide Federal contribution to the conservation of spotted owls and its habitat.  Specifically, late successional reserves (LSRs) were created under the NWFP to provide large blocks of suitable habitat capable of supporting multiple pairs of spotted owls.  Standards and Guidelines of the NWFP establish that LSRs will be managed to protect and enhance late-successional and old-growth forests ecosystems.  Riparian Reserves and other NWFP land use allocations provide for connectivity between reserves.  Approximately 70 percent of suitable habitat in CHUs overlaps with NWFP LSRs on a range-wide basis and will therefore be managed to protect and enhance habitat characteristics.

 

3.4 Current Condition of Critical Habitat

 

3.4.1 Range-wide

In 1994, the FSEIS for the NWFP established that 3,141,987 acres of NRF habitat existed within spotted owl CHUs on federally administered public lands.  To assess changes to the baseline condition since implementation of the NWFP, the Service relies on information in section 7 consultations and available information on natural events.  Hereafter, effects to critical habitat refer to NRF habitat within spotted owl critical habitat.

 

Across the range of the spotted owl between 1994 and August 31, 2006, the Service has consulted on the removal or downgrading of 41,947 acres (1.34 %) of critical habitat due to management-related activities, and an additional 39,078 acres have been removed or downgraded due to natural events (i.e. insect damage, fire) (Table 11).  The majority of these consulted-on effects, 28,156 acres (67%), have been concentrated in the Oregon Cascades West and Oregon Klamath Mountains Provinces.  In addition, natural events (including fire and insect outbreaks) have resulted in the removal or downgrading of approximately 39,078 acres (1.24 %) of critical habitat extant in 1994.  In general, fires have had more of an impact to spotted owl critical habitat in the interior provinces of Washington and California and the southern and interior provinces of Oregon than the coastal provinces. 

 

Consultation data indicate effects to critical habitat within each physiographic province have not been evenly distributed range-wide.  The majority of the effects (approximately 57.79 % totaling 46,825 acres) to suitable spotted owl critical habitat range-wide have occurred in the Oregon Klamath Mountains and Western Oregon Cascades physiographic provinces (Table 11).  Besides providing large blocks of suitable habitat to support population clusters and intra-provincial connectivity, these provinces also provide important inter-provincial links.  The Oregon Klamath Mountains province provides a link between the Oregon Coast Range and Western Oregon Cascades provinces and south into the northern California provinces.  The northern portion of the Western Oregon Cascades province provides the link to the Washington Cascades across the Columbia Gorge area of concern while the southern portion of this province shares the three linkage areas within the I-5 area of concern which connect this province with the Oregon Coast Range and Oregon Klamath Mountains provinces (USFWS 2001a).

 

Consultation data also indicates that percent of effects to critical habitat within each physiographic province have not been evenly distributed.  Although there is not as much of a spread as the range-wide effects, two physiographic provinces have greater than 3 percent of critical habitat removed or downgraded since 1994.  Klamath Mountains has had 8.51 percent of the provincial base line affected, and Cascade East has had 6.05 percent of the provincial base line affected.  Of the remaining seven provinces, one (Oregon Willamette Valley) had no designated critical habitat, one (Washington Western Lowlands) had no suitable habitat within critical habitat, and six provinces (Olympic Peninsula, Oregon Coast Range, Oregon Klamath Mountains, California Coast Range, California Cascades) had less than 3 percent of the critical habitat removed or downgraded since 1994.

 

3.4.2 Provinces with the Majority of Impacts Range-wide or to Their Baseline

3.4.2.1 Oregon Klamath Mountains.  The Oregon Klamath Mountains Province contains 16 CHUs and provides the link between the Oregon Cascades West and Oregon Coast Ranges Province south into California. 

 

Between 1994 and July 19, 2005, the Spotted Owl Coordination Team estimated this province has had more critical habitat removed or downgraded than any other province: 30,380 acres or approximately 10 percent.  In general, effects to critical habitat have been evenly distributed between those consulted upon (12,927 acres) and those attributable to fire (17,453 acres) effects.  Although consulted-on effects were distributed across 11 CHUs, approximately 36 percent of consulted-on effects have occurred in two adjacent units (OR-74 and OR-75).  Together, these units provide an east-west linkage in the southern portion of the Klamath Mountains Province and provide essential NRF, and dispersal habitat in a highly fragmented area (Tweten 1992).  The majority of fire effects in this province can be attributed to the Biscuit Fire.  This fire removed or downgraded approximately 23, 46, and 37 percent of the suitable habitat within OR-68, OR-69, and OR-70, respectively.  These units were identified for their important contributions to inter- and intra-provincial connectivity and to provide essential NRF and dispersal habitat in areas where habitat is lacking (Tweten 1992).

 

Since the Spotted Owl Coordination Team’s update the Biscuit fire effects plus other effects added to the Services tracking system resulting in new total of 26,672 acres removed or downgraded from this province or 8.51 percent of the Provincial baseline has been affected (32.92 % of the rage-wide affects).

 

3.4.2.2 Oregon Cascades West.  This province is located in the geographic center of the spotted owl’s range and contains more critical habitat (over 894,000 acres) than any other province.  It provides links with the Washington Cascades, Oregon Coast Range, and Klamath Mountains Provinces. 

 

Between 1994 and July 19, 2005, the Spotted Owl Coordination Team estimated approximately 21,297 acres or 2.38 percent of its provincial baseline have been removed or downgraded.  Consulted-on effects have been widely dispersed within 26 of the 29 CHUs in this province.  In general, this has resulted in relatively small impacts to individual units.  However, two adjacent units, OR-23 and OR-24, have experienced relatively concentrated effects having 215 acres (14.3 %) and 946 acres (48.8 %) removed or downgraded, respectively.  Together these units were identified as being important inter-provincial links between the Coast Ranges and the Oregon Cascades West Provinces (Tweten 1992).  Fire has had limited effects to spotted owl critical habitat in this province: 1,216 acres or less than 0.5 percent of the provincial baseline have been removed or downgraded by fire.

 

Since the Spotted Owl Coordination Team’s update, the fire effects plus other effects added to the Services tracking system resulting in new total of 20,153 acres removed or downgraded from this province or 2.25 percent of the Provincial baseline has been affected (24.87 % of the range-wide affects).

 

3.4.2.3 Oregon Cascades East.  The Oregon Cascades East Province provides the easterly extension of the spotted owl’s range in Oregon and contains all or portions of 10 CHUs. 

 

Between 1994 and July 19, 2005, the Spotted Owl Coordination Team estimated approximately 8,584 acres or 6.18 percent of its provincial baseline have been removed or downgraded.  The majority of these acres, approximately 6,878, are a result of several fires during 2002 and 2003.  The impacts of these fires were concentrated in the central portion of this province where approximately 20 percent of the extant suitable habitat in OR-3 and OR-4 and over 36 percent of the suitable habitat in OR-7 were removed or downgraded.  OR-3 and OR-4 were designated to maintain suitable habitat and support dispersal along the eastern slope of the Oregon Cascades (Tweten 1992).  OR-7 provides a north-south link within the province and an inter-provincial link with the Oregon Cascades West Province.  Consulted-on effects have been evenly distributed, occurring in 8 of 10 CHUs, and have resulted in less than a 5 percent reduction (through removal or downgrading) of suitable habitat within any individual CHU.

 

Since the Spotted Owl Coordination Team’s update, the fire effects plus other effects added to the Services tracking system resulting in new total of 8,388 acres removed or downgraded from this province or 6.05 percent of the Provincial baseline has been affected (10.35 % of the range-wide affects).

 

3.4.3 Summary

This evaluation of critical habitat indicates that effects since 1994 may have somewhat impaired, to varying degrees, the ability of individual CHUs to fulfill their intended functions.  However, these effects have not prevented the CHU network from providing for spotted owl conservation (i.e. recovery) across the species range.  The Service reached this conclusion based on the following reasons: (1) only 2.58 percent of designated critical habitat has been affected range-wide; (2) although the majority of effects occurred in the Oregon Klamath Mountain and Western Oregon Cascades Provinces, the CHU network within these provinces continues to contribute to spotted owl recovery; (3) notwithstanding that natural disturbances have resulted in the removal and degradation of large blocks of suitable habitat and reduced the resilience of the CHU network to future effects, they have not prevented the CHU network from functioning to promote recovery of the owl within any province.

 

The NWFP’s network of LSRs overlap designated critical habitat by about 70 percent along with owl habitat in other LUAs and in the matrix contributing to connectivity (and some population support).  Although the NWFP was designed using the ISC principles and incorporated recommendations from the owl recovery team (USFWS 1992b), it did not substitute for the network of designated critical habitat.  The assessment of critical habitat condition and function for this BO was analyzed independent of the contribution that the LSR network provides to spotted owl conservation (see Status of the Species in the Action Area below).


 

 

Table 11.  Aggregate results of all adjusted, suitable critical habitat 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 August 31, 2006.

Physiographic

Province3

 

Evaluation Baseline1

Habitat Removed/Downgraded2

% Provincial

Baseline Affected

% Range-wide

Affected

Reserves4

Non-Reserves5

Habitat Loss to Natural Events

Total

 

 

WA

 

 

 

Olympic Peninsula

197009

12

59

0

71

0.04

0.09

Eastern Cascades

326592

87

4549

3856

8492

2.60

10.48

Western Cascades

514578

4

5040

0

5044

0.98

6.23

Western Lowlands

0

0

0

0

0

0.00

0.00

OR

 

 

 

 

Coast Range

348717

50

1200

0

1250

0.36

1.54

Klamath Mountains

313269

6

9213

17453

26672

8.51

32.92

Cascades East

138684

138

1372

6878

8388

6.05

10.35

Cascades West

894134

63

18874

12163

20153

2.25

24.87

Willamette Valley

0

0

0

0

0

0.00

0.00

CA

 

 

Coast

2616

0

0

0

0

0.00

0.00

Cascades

50687

0

472

0

472

0.93

0.58

Klamath

355701

0

808

9675

10483

2.95

12.94

Total

3141987

360

41587

39078

81025

2.58

100.00

11994 FSEIS baseline (USDA and USDI 1994b).

2 Includes both effects reported in USDI FWS 2001 and subsequent effects reported in the Northern Spotted Owl Consultation Effects Tracking System (web application and database.)

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

4Land-use allocations intended to provide large blocks of habitat to support clusters of breeding pairs.

5Land-use allocations intended to provide habitat to support movement of spotted owls among reserves.

 


4.0 Analysis of Species/Critical Habitat

 

4.1 Concurrence for Spotted Owl

 

The proposed project occurs in dispersal habitat and since the stands are not yet suitable habitat the project should not significantly affect spotted owls.  Resident spotted owls in the area are expected to have minor to no impacts, as their foraging base should not be affected.  Minor impacts to resident spotted owls would be due to thinning next to suitable habitat creating an edge.  Although any edge effects from harvest will be small due to the proposed project is a thinning and remaining trees will help reduce wind throw or microclimate changes.  Additionally, the landscape will still support dispersing spotted owls post-treatment of stands, as per management standard nine.  Therefore, the Service concurs with the FS that the proposed action’s modification of spotted owl habitat may affect, but is not likely to adversely affect spotted owls (Table 12).

 

The proposed project will also occur during the spotted owl breeding period, although all significant impacts are being avoided.  Standard four, prohibits an activity that would disrupt spotted owls during their critical breeding period.  In the late breeding period, most spotted owls have fledged from the nest and are capable of short flights and therefore can distance themselves from disturbances without expected harm, except for large helicopter disturbance.  The disruption from a large helicopter is larger then other disturbances (estimated to create significant noise to disrupt spotted owls out to 120 yards), and therefore the greater distance needed for a fledgling to move to avoid this disruption places them at a greater risk.  Only three activity centers are within 120 yards of a harvest unit.  Of the three sites only one, 208, is planned to be helicopter logged, but not until after the spotted owl breeding season (as per Sharron Hernandez, contact biologist for this project, Mt. Hood NF).  Therefore, no breeding spotted owls with fledglings should be disturbed.  Adult spotted owls not tending young are expected to be able to move away form a disturbance without significantly impacting breeding, feeding or sheltering.  Therefore, the Service concurs with the FS that the proposed action’s disturbance may affect, but is not likely to adversely affect spotted owls (Table 12).

 

Since the Service concurs with the FS determination of “is not likely to adversely affect,” for spotted owls, this species will not be considered further in the consultation.  Only effects to spotted owl Critical habitat are further analyzed.

 

Table 12.  Summary of effects calls to northern spotted owls, 2007 Plantation Thin, Mt. Hood NF.

Activity Type

Habitat Modification

DISTURBANCE

CRITICAL HABITAT MODIFICATION

Not likely to adversely affect (NLAA)

NLAA

No Effect

NLAA

LAA

Acres

Acres

Acres

ACRES

ACRES

Heavy Thinning and Road Construction

5,860

5,860

0

0

2,320

Light to Moderate Thinning

750

750

0

400

0

Total

6,610

6,610

0

400

2,320

 

4.2 Spotted Owl Critical Habitat

 

Impacts to the primary constituent elements are expected due to the removal of dispersal habitat.  Therefore critical habitat is likely to be adversely affected by the proposed action (Table 12) and will be considered further in the remaining sections of the biological opinion.

 

5.0 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].

 

5.1 Spotted Owl Critical Habitat

 

The proposed project will affect 2,720 acres of critical habitat within the action area.  The affected CHUs are OR-10 and OR-12.  The status of spotted owl habitat within each affected CHU is provided in Table 13.  The designated functions of CHUs in the survival and recovery of spotted owl which occur in the action area are displayed in Table 14.

Table 13.  Current status of spotted owl Critical Habitat Units by Northwest Forest Plan allocation and by Unit.

 

Matrix Acres

Adaptive Management Area Acres

Late Successional Reserve Acres

Administratively Withdrawn Acres

Congres­sionally Withdrawn Acres

Total Acres

OR-10 – Mt Hood NF

Suitable

14,478

0

22,817

1,590

265

39,150 (44%)

Dispersal

5,939

0

10,451

395

138

16,923 (19%)

Capable – Currently non-habitat

11,585

0

9,678

779

9

22,051 (25%)

Non-Capable*

1,568

0

7,953

966

0

10,487 (12%)

Totals

33,570 (38%)

0

50,899 (57%)

3,730 (4%)

412 (0%)

88,611

* Non-capable includes areas such as lakes, rivers, rock outcroppings, roads, poor soil conditions as well as those above 4500 feet in elevation.

Some cells updated in 2004 to reflect changes due to past harvest, land exchanges, and updated GIS databases.

OR-10 – Salem BLM

Suitable

139

0

0

0

0

139 (66%)

Dispersal

6

0

0

0

0

6 (3%)

Capable – Currently non-habitat

56

0

0

0

0

56 (27%)

Non-Capable*

9

0

0

0

0

9 (4%)

Totals

210 (100%)

0

0

0

0

210

OR-12 – Mt Hood NF

Suitable

7,939

0

11,580

214

2

19,735 (52%)

Dispersal

780

0

858

988

0

2,626 (7%)

Capable – Currently non-habitat

8,096

0

4,311

347

0

12,754 (34%)

Non-Capable*

1,900

0

495

137

0

2,532 (7%)

Totals

18,715 (50%)

0

17,244 (46%)

1,686 (4%)

2 (0%)

37,647

OR-12 – Salem BLM (includes Table Rock Wilderness)

Suitable

552

0

9,168

0

4,974

14,694 (59%)

Dispersal

408

0

1,444

0

349

2,201 (9%)

Capable – Currently non-habitat

842

0

5,586

0

68

6,496 (26%)

Non-Capable*

82

0

1,060

0

308

1,450 (6%)

Totals

1,884 (8%)

0

17,258 (69%)

0

5,699 (23%)

24,841

* Non-capable includes areas such as lakes, rivers, rock outcroppings, roads, poor soil conditions as well as those above 4500 feet in elevation.

Some cells updated in 2004 to reflect changes due to past harvest, land exchanges, and updated GIS databases.

 

Table 14.  Designated functions of Critical Habitat Units (CHU) occurring within the action area.

Designated Function of spotted owl Critical Habitat Units (CHU) within the action area.

 

 

OR-10

Designated to maintain and provide essential NRF habitat and support a cluster of owl pairs.  Unit OR-10 provides an important link in the north-south continuum of owl habitat between units OR-12 and OR-2 to the south and OR-9 and OR-1 to the north as well as within the Western Cascades province as a whole.  57% LSR overlap with larger, northern portion of RO207.

OR-12

Designated to maintain and provide essential nesting, roosting, and foraging habitat and support a cluster of owl pairs.  Unit OR-12 helps maintain range-wide distribution of suitable nesting habitat in the northern portion of the Western Cascades province and helps maintain a strong north-south distribution of suitable nesting habitat by linking units OR-10, OR-11, OR-13, and OR-14.  54% LSR overlap with RO209 and RO210.

 

5.1.1 OR-10

This CHU encompasses approximately 88,821 acres.  It is mostly located within the Clackamas River and Zigzag Ranger Districts of the Mt. Hood National Forest, with a very small portion occurring within the Salem Bureau of Land Management.  Approximately 37,510 acres of this CHU falls outside of LSR’s and wilderness areas (Table 13).  OR-10 was established to provide suitable habitat for spotted owls.  It also provides an important link between OR-12 and 11 to the south and OR-9 and 1 to the north.  OR-10 overlaps with LSR 205, 207a and b, as well as small portion of the Salmon-Huckleberry Wilderness.    The portion of LSR 207b associated with OR-10 is a narrow corridor along the Clackamas River providing a dispersal corridor for spotted owls.  A portion of the Timothy Lake Mt. Hood Area of Concern for spotted owl dispersal overlaps OR-10, but does not overlap the action area.

 

5.1.2 OR-12

OR-12 is located within the southern boundary of the Mt. Hood National Forest.  The CHU encompasses lands within the Mt. Hood National Forest and the Salem Bureau of Land Management, including Table Rock Wilderness.  OR-12 encompasses approximately 62,488 acres (Table 13).  Approximately 22,285 acres of this CHU falls outside of LSR’s and wilderness boundaries (Table 13).  Only approximately 1,884 acres of the Salem BLM ownership occurs outside of the LSR’s and Table Rock Wilderness. 

 

5.1.3 Physiographic Province

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

 

5.1.3.1 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 894,134 acres of suitable habitat on Federal lands within this province, with 45,339 acres being removed or downgraded through August 8, 2006, resulting in a decrease of 2.32 percent of the provincial baseline (Table 7). 

 

6.0 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 dealing with effects to critical habitat.  Second, there is a specific discussion on the effect of each proposed activities as they relates to critical habitat issues for the spotted owl.  The activities are heavy thinning with associated actions, light to moderate thinning with associated actions and a separate discussion on instream habitat restoration since this activity is in the riparian buffer and not within the treatment areas.

 

6.1 Spotted Owl Critical Habitat

 

Designation of critical habitat serves to identify lands which are necessary for the conservation (i.e. recovery) of listed species.  Approximately 6.9 million acres across Washington, Oregon, and California were designated in a manner that would protect clusters of reproductively-capable spotted owls and facilitate demographic interchange.  The Service’s primary objective in designating critical habitat was to identify existing spotted owl habitat and highlight specific areas where management should be given highest priority.  The primary constituent elements of spotted owl critical habitat are those physical and biological habitat features which support nesting, roosting, foraging, and dispersal.  Any activity occurring within designated critical habitat which impacts any of these primary constituent elements may affect spotted owl critical habitat.

 

Given the above concerns, Table 15 lists the different actions that are likely to affect spotted owl critical habitat, and the rationale for the effect.  Table 16 list the activity types, associated action and summary of effects to spotted owl critical habitat.

 

Table 15.  Effects of the proposed action on spotted owl critical habitat, 2007 Plantation Thin, Mt. Hood NF.

Action

Effect

Rationale for Effect Determination

Remove dispersal habitat

 

MA,LAA1

 

Removal of dispersal critical habitat may affect, and is likely to adversely affect spotted critical habitat due to the removal of all the primary constituent elements present in the stand.  This action will remove all spotted owl habitat within the stand.  Even though some structural components (snags, clumps of large trees, down wood) will be retained to meet existing NWFP requirements, the overall affect to spotted owl habitat is that it will be set back for 30-40 years before it provides stand conditions suitable for owl dispersal and over 80 years before it functions as NRF spotted owl habitat.  Although some heavy thinning prescriptions will likely accelerate the stands on a faster trajectory to suitable habitat then before harvest, there is still the short term loss of dispersal habitat.  Therefore, the removal of dispersal spotted owl critical habitat will affect the conservation value of critical habitat to support spotted owls.

Degrade dispersal habitat

MA,NLAA

 

Degrading of dispersal critical habitat is not likely to have a measurable effect on the ability of the stand to contribute to the conservation of spotted owls, since primary constituent elements supporting dispersal habitat will be maintained.  The stands will maintain a 40 percent or greater canopy cover in addition to some structural components (snags, clumps of large trees, down wood) to meet existing NWFP requirements.

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

2 MA,NLAA = may affect, but is not likely to adversely affect


Table 16.  Summary of effects determinations to spotted owl critical habitat from habitat modification performed in compliance with the Management Standards in Section 1.2.  

Activity Type

Habitat/action

Effect to Critical Habitat

Heavy Thinning

(including within the unit boundary: Road construction, Post-Harvest Fuels Treatment, Terrestrial Habitat Enhancement, and Post-harvest Firewood sales)1, 2

Dispersal3/removed

MA-LAA 4

Light to Moderate Thinning

(including within the unit boundary: Post-Harvest Fuels Treatment, Terrestrial Habitat Enhancement, and Post-harvest Firewood sales) 2

Dispersal/degrade

MA-NLAA4

Instream Habitat Restoration5

Dispersal/degrade

MA-NLAA

1 The dispersal acres removed for road-construction are included within the dispersal acres removed through the commercial thin.  The number of dispersal acres removed through the road construction is very small and has similar short-term effects as the heavy thinning.

2 The post-harvest firewood sales, terrestrial habitat improvement projects and fuels treatments all occur within the unit boundaries and are not displayed in the above table.  The acres of habitat affected would be the same acres as those impacted by the commercial thin.  The additional degradation of habitat would be minimal and would not exceed what is already displayed in this table.

3 This action will only occur in situations where the availability of dispersal habitat is not limiting in the area of consideration.  This may include long-term beneficial effects from treatments designed to encourage faster or desirable late-successional conditions.

4    MA-NLAA = May affect but not likely to adversely affect
MA-LAA = May affect and likely to adversely affect

5 The instream treatments would occur within the stream no-harvest cut buffers of the proposed harvest units.  Due to the small amounts of second-growth trees cut and left on site within these areas, no additional impacts to spotted owls are expected.

 

7.0 Effects of the Action BY ACTIVITY TYPE

 

Effect determinations are summarized in Table 12.

 

7.1 Heavy Thinning

 

This activity is expected to downgrade habitat due to the removal of trees for road construction, harvest prescription, terrestrial habitat enhancement (down wood and snag creation), and post-harvest firewood sales, produce smoke from post harvest fuels treatment and generate above ambient noise levels due to use of chainsaw and heavy equipment.

 

7.1.1 Spotted Owl Critical Habitat

Heavy thinning of 2,320 acres of dispersal critical habitat may affect, and is likely to adversely affect spotted owl critical habitat because such harvest would remove all primary constituent elements supporting dispersal in the harvest units.  Even though some structural components (snags, clumps of large trees, down wood) will be retained to meet existing NWFP requirements, the overall effect to dispersal critical spotted owl habitat is that it eliminates its current conservation value to the species and sets back the development of suitable habitat.  However, long-term effects could be beneficial because the proposed harvest treatments are predicted to eventually improve the quality of dispersal habitat in many of the units and potentially speed up the succession of some of these stands into suitable habitat.  The treatments would include a thinning prescription that would increase growth of the residual stand.  Larger trees would eventually be provided in these young managed plantations in a much faster timeframe than they would if no management occurred.  In addition, a variable density thin would occur both between trees in the units and between stands, thus adding to the potential that the units will eventual provide diverse habitat attributes.  Skips and gaps would be incorporated into the prescriptions, also adding to the potential for increased habitat diversity in the future.  These silvicultural techniques are more likely to push the stands to an accelerated trajectory that would more quickly provide suitable habitat than if no management occurred.

 

7.2 Light to Moderate Thinning

 

This activity is expected to degrade habitat due to the removal of trees for the harvest prescription, terrestrial habitat enhancement (down wood and snag creation), and post-harvest firewood sales, produce smoke from post harvest fuels treatment and generate above ambient noise levels due to use of chainsaw and heavy equipment.

 

7.2.1 Spotted Owl Critical Habitat

Light to moderate thinning of 400 acres of dispersal critical habitat may affect spotted owls because this type of activity could reduce the canopy closure of stands used for dispersal to as low as 40 percent.  Because the primary constituent element supporting dispersal will be maintained (stands will be degraded), thinning of these stands may affect, but is not likely to adversely affect spotted owl critical habitat.

 

7.3 Instream Habitat Restoration

 

This activity is expected to remove large individual trees within the units no-harvest cut riparian buffers and generate above ambient noise levels due to use of chainsaws. 

 

7.3.1 Spotted Owl Critical Habitat

The loss of trees in dispersal critical habitat may affect, but is not likely to adversely affect spotted owl critical habitat because such trees will be scattered throughout the no-harvest cut riparian buffers within the harvest units.  Therefore, the removal of these trees will only degrade dispersal critical habitat, and riparian buffers will still be able to support spotted owl dispersing.  The riparian buffers will still contain the primary constituent elements to support dispersal.

 

7.4 Summary of Effects

 

7.4.1 Spotted Owl Critical Habitat

The Service agrees with the BA that the treatment of 2,320 acres which will remove dispersal critical habitat may affect, and is likely to adversely affect spotted owl critical habitat.  The Service concurs with the BA that treatment of 400 acres which will degrade dispersal critical habitat may affect, but is not likely to adversely affect spotted owl critical habitat. 

 

8.0 COMBINED Effects to Critical habitat

 

Table 17 describes the effects to individual Critical Habitat Units affected by proposed activities.

 

Table 17.  2007 Plantation Thin proposed treatments as related to specific critical habitat units for the northern spotted owl.

Critical Habitat Unit

Dispersal Habitat (Includes Suitable and Dispersal-only habitat)

Total acres affected

Total Acres

Total Acres Removed

Total Acres Remaining Post-harvest

percent of habitat Removed

Acres Degraded

OR-10

56,218

1,835

54,383

3.3%

300

2,135

OR-12

39,256

485

38,771

1.2%

100

585

Total

95,474

2,320

93,154

2.4%

400

2,720

 

8.1 Critical Habitat Unit OR-10

 

The 2007 Plantation Thin proposes to modify northern spotted owl habitat by removing up to 1,835 acres and degrading up to 300 acres of dispersal-only habitat within CHU OR-10.  Even though the structural components (snags, remnant trees, down wood) will be retained to meet existing Mt. Hood Forest Plan and Northwest Forest Plan requirements, the overall affect will be a temporary loss of up to 1,835 acres of dispersal habitat within CHU OR-10.  Habitat conditions in these stands are expected to once again provide conditions suitable for dispersal habitat in approximately 5-10 years.  In 15-25 years these stands would again provide the same quality of dispersal habitat as pre-treatment conditions.  The 300 acres that would be degraded in this CHU would continue to provide dispersal habitat following treatment, although be reduced in quality.  These stands would again provide the same quality of dispersal habitat as pre-treatment conditions in about 10-20 years.  

 

There are currently 39,289 acres of NRF habitat and 16,929 acres of dispersal-only habitat distributed across this CHU (Table 13).  The proposed action will have no effect on suitable habitat and will reduce the amount of the total that could function as dispersal (dispersal + suitable) habitat to 54,383 acres, a reduction of 3.3 percent.  Additionally, another proposed project that is in formal consultation (1-7-06-F-0179) with the Service will be removing 2,550 acres from this CHU (250 acres downgraded from heavy thinning and 2,300 acres removed from dispersal; 100 acres from regeneration harvest and 2,200 acres from heavy thinning).  With these additional effects added together, the change in baseline acres for this CHU is 7.8 percent.  Dispersal critical habitat will be temporarily set back by the 2007 Plantation Thin, but spotted owl dispersal abilities within this Province will not be limited and treated stands have the possibility to accelerate their development into suitable habitat, as compared to no treatment.  The degradation of 300 acres of dispersal habitat would not result in the loss of functionality and therefore will still be able to support the conservation role of providing dispersal habitat. 

 

8.2 Critical Habitat Unit OR-12

 

The 2007 Plantation Thin proposes to modify northern spotted owl habitat by removing up to 485 acres and degrading up to 100 acres of dispersal-only habitat within CHU OR-12.  Even though the structural components (snags, remnant trees, down wood, etc.) will be retained to meet existing Mt. Hood Forest Plan and Northwest Forest Plan requirements, the overall affect will be a temporary loss of up to 485 acres of dispersal habitat within CHU OR-12.  Habitat conditions in these stands are expected to once again provide conditions suitable for dispersal habitat in approximately 5-10 years.  In 15-25 years they would again provide the same quality of dispersal habitat as pre-treatment conditions.  The 100 acres that would be degraded in this CHU would continue to provide dispersal habitat following treatment, although be reduced in quality.  These stands treated would again provide the same quality of dispersal habitat as pre-treatment conditions in about 10-20 years.  

 

There are currently 34,429 acres of NRF habitat and 4,827 acres of dispersal-only habitat distributed across this CHU (Table 13).  The proposed action will have no effect on suitable habitat and will reduce the amount of the total that could function as dispersal (dispersal + suitable) habitat to 38,771 acres, a reduction of 1.2 percent.  Dispersal critical habitat will be temporarily set back by the 2007 Plantation Thin, but spotted owl dispersal abilities within this Province will not be limited and treated stands have the possibility to accelerate there development into suitable habitat, as compared to no treatment.  The degradation of an additional 100 acres of dispersal habitat would not result in the loss of functionality and therefore will still be able to support the conservation role of providing dispersal habitat.

 

8.3 Fragmentation between Critical Habitat Units

  

Many of the proposed harvest units occur within lands between OR -10 and 12.  Currently there is not a concern for dispersal between these two units.  The network of dispersal and suitable habitat is considered adequate between the two units.  Although there would still be adequate dispersal habitat between OR-10 and 12 post-harvest, the effectiveness of the area as a whole to provide dispersal opportunities for owls between these two units would be reduced in quality for the short-term.

 

8.4 Oregon Western Cascades Physiographic Province

 

Adverse effects will result from a total of 2,320 acres of dispersal habitat removed due to heavy thinning.  These effects represent no change to the suitable critical habitat baseline for the Oregon Western Cascade Physiographic Province.  Dispersal critical habitat will be temporarily set back, but will not limit dispersal abilities within this Province and treated stands have the possibility to accelerate there development into suitable habitat, as compared to no treatment. 

 

8.5 Range-wide

 

Adverse effects will result from a total of 2,320 acres of dispersal habitat removed from critical habitat due to heavy thinning.  These affects represent no change to the suitable critical habitat range-wide baseline.  Due to the small impact to dispersal critical habitat, the proposed project will not impact the conservation value of critical habitat.  Therefore, the proposed action would not preclude or significantly delay the attainment of critical habitat conditions. 

 

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.

 

There are no non-federal lands within the action area.  Therefore, there are no cumulative effects.

 

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 owl critical habitat, and the cumulative effects, it is the Service’s biological opinion that the activities, as proposed, are not likely to adversely modify spotted owl critical habitat.

 

We reached this conclusion 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 conservation role of the action area with respect to spotted owl critical habitat.  Implementation of the proposed action will not remove any suitable habitat; removal of dispersal habitat will not limit the dispersal ability of critical habitat; and thinning prescriptions have the potential to accelerate the development of suitable habitat as compared to untreated stands.  Therefore, the conservation function of critical habitat is maintained at the Oregon Western Cascades Physiographic Province, and range-wide (NWFP) scales.

 

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

 

Since the project design including Management Standards, were developed to included measures to avoid incidental take, no incidental take of spotted owls is expected.

 

12.0 Reasonable and Prudent Measures

 

Not applicable

 

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 disrupt 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. 

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