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Final Biological Assessment

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Final Biological Assessment REVISED BIOLOGICAL ASSESSMENT Effects of the Modified Idaho Roadless Rule on Federally Listed Threatened, Endangered, Candidate, and Proposed Species for Terrestrial Wildlife, Aquatics, and Plants September 12, 2008 FINAL BIOLOGICAL ASSESSMENT Effects of the Modified Idaho Roadless Rule on Federally Listed Threatened, Endangered, Candidate, and Proposed Species for Terrestrial Wildlife, Aquatics, and Plants Table of Contents I. INTRODUCTION.......................................................................................................................................... 1 II. DESCRIPTION OF THE FEDERAL ACTION .................................................................................................... 3 Purpose and Need..................................................................................................................................3 Description of the Project Area...............................................................................................................4 Modified Idaho Roadless Rule................................................................................................................6 Wild Land Recreation (WLR)...............................................................................................................6 Primitive (PRIM) and Special Areas of Historic and Tribal Significance (SAHTS)..............................7 Backcountry/ Restoration (Backcountry) (BCR)................................................................................10 General Forest, Rangeland, or Grassland (GFRG) ..........................................................................13 Guidance that Applies to all Idaho Roadless Areas .............................................................................15 Permanent Roads .............................................................................................................................15 Temporary Roads..............................................................................................................................15 Road maintenance ............................................................................................................................15 Other Forest Plan Special Areas.......................................................................................................15 Other Activities in Idaho Roadless Areas..........................................................................................15 Grizzly Bear Considerations..............................................................................................................15 Administrative Corrections ................................................................................................................16 Modifications .....................................................................................................................................16 Scope and Applicability. ....................................................................................................................17 Relationship to Current Guidance and Analysis of the Modified Rule..................................................17 Relation of the Modified Rule to the 2001 Roadless Rule ................................................................18 Relation of the Modified Rule to the Existing Forest Plans ...............................................................19 Definitions..........................................................................................................................................22 Assumptions .........................................................................................................................................24 Numbers used in this report: .............................................................................................................24 Assumptions - General......................................................................................................................24 Assumptions – Timber Cutting ..........................................................................................................25 Assumptions – Road Construction....................................................................................................25 Assumptions – Discretionary Minerals ..............................................................................................27 III. CONSULTATION HISTORY ...................................................................................................................... 28 Meetings, Conference Calls, and Correspondence..............................................................................29 IV. EFFECTS OF THE MODIFIED IDAHO ROADLESS RULE ON FEDERALLY LISTED AQUATIC SPECIES .............. 33 Background...........................................................................................................................................33 Information Used ...............................................................................................................................33 Analysis Process Used......................................................................................................................34 Aquatic Assumptions and Conservation Rules of Thumb Considered During Analysis ...................34 Questions Utilized to Determine Effects to Aquatic Species and Their Habitat................................35 Tribal Values .....................................................................................................................................35 General Aquatic Species Information...................................................................................................36 Evolutionarily Significant Units and Distinct Population Segments Within the Action Area..............36 Essential Fish Habitat........................................................................................................................38 Bull Trout Key Recovery Habitat .......................................................................................................39 Bull Trout Core Areas........................................................................................................................41 Priority Watersheds ...........................................................................................................................43 Fish Strongholds ...............................................................................................................................44 Threatened and Endangered Fish Species Richness.......................................................................48 General Effects of Management Activities on Aquatic Habitats and Species ......................................51 Roads ................................................................................................................................................51 Timber Cutting...................................................................................................................................54 Mineral Activities ...............................................................................................................................55 Extent and Duration of Effects ..........................................................................................................56 Consideration of Non-Federal Activities Outside the Idaho Roadless Areas.......................................57 Table of Contents _____________________________________________________________________________ i FINAL BIOLOGICAL ASSESSMENT Effects of the Modified Idaho Roadless Rule on Federally Listed Threatened, Endangered, Candidate, and Proposed Species for Terrestrial Wildlife, Aquatics, and Plants State, Local Government, Tribal and Private Actions .......................................................................57 Local Government Actions ................................................................................................................59 Tribal Actions.....................................................................................................................................59 Private Actions ..................................................................................................................................59 Ongoing and Reasonably Foreseeable Federal Actions ..................................................................60 Measures Common to All Species to Avoid or Minimize Effects..........................................................60 Effects of the Proposed Action – Modified Idaho Roadless Rule on Aquatic T&E Species.................62 Specific Effects of Management Activities on Aquatic Species in Idaho Roadless Areas................62 Cumulative Effects—Aquatic Species...............................................................................................63 Non-Federal Habitat ..........................................................................................................................64 Non-native Invasive Species.............................................................................................................64 Impacts of Past Direction ..................................................................................................................64 Impacts of Existing Management Practices ......................................................................................65 Fire ....................................................................................................................................................65
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