Endangered Species Act (ESA) Section 7(a)(2) Biological Opinion for Construction of the Tongass Narrows Project (Gravina Access) Public Consultation Tracking System (PCTS) Number: AKR-2018-9806 Action Agencies: Alaska Department of Transportation and Public Facilities (ADOT&PF) on behalf of the Federal Highway Administration (FHA) Affected Species and Determinations: Is Action Likely Is Action Likely Is Action to Adversely To Destroy or Likely To ESA-Listed Species Status Affect Species or Adversely Jeopardize Critical Modify Critical the Species? Habitat? Habitat? Humpback whale (Megaptera Threatened Yes No N/A novaeangliae) Mexico DPS Consultation Conducted By: National Marine Fisheries Service Issued By: ____________________________________ James W. Balsiger, Ph.D. Administrator, Alaska Region Date: February 6, 2019 Ketchikan Tongass Narrows Project PCTS AKR-2018-9806 TABLE OF CONTENTS List of Tables .................................................................................................................................. 4 List of Figures ................................................................................................................................. 4 Terms and Abbreviations ................................................................................................................ 6 1. Introduction ............................................................................................................................. 8 1.1 Background ...................................................................................................................... 8 1.2 Consultation History ........................................................................................................ 9 2. Description of the Proposed Action and Action Area .......................................................... 10 2.1 Proposed Action ............................................................................................................. 10 2.1.1 Proposed activities: project components ................................................................. 10 2.1.2 Proposed activities: construction methods .............................................................. 18 2.1.3 Acoustic sources ..................................................................................................... 25 2.1.4 Mitigation measures ................................................................................................ 28 2.2 Action Area .................................................................................................................... 44 3. Approach to the Assessment ................................................................................................. 47 4. Rangewide Status of the Species and Critical Habitat .......................................................... 48 4.1 Climate Change .............................................................................................................. 49 4.2 Status of Listed Species.................................................................................................. 49 4.2.1 Humpback whale (Megaptera novaeangliae) ......................................................... 50 5. Environmental Baseline ........................................................................................................ 56 5.1 Physical Environment .................................................................................................... 56 5.2 Fish and Essential Fish Habitat ...................................................................................... 57 5.3 Marine Vessel Activity................................................................................................... 57 5.4 Fishery Interactions Including Entanglements ............................................................... 59 5.5 Pollution ......................................................................................................................... 59 5.6 Climate and Ocean Regime Change............................................................................... 60 5.7 Coastal Zone Development ............................................................................................ 61 5.8 In-Water Noise ............................................................................................................... 61 5.9 Competition for Prey ...................................................................................................... 61 6. Effects of the Action ............................................................................................................. 61 6.1 Project Stressors ............................................................................................................. 62 6.2 Stressors Unlikely to Occur or Likely to Have Negligible Impacts on ESA-listed Species ...................................................................................................................................... 63 6.2.1 Injury or disturbance due to construction vessel traffic .......................................... 63 2 Ketchikan Tongass Narrows Project PCTS AKR-2018-9806 6.2.2 Disturbance to seafloor ........................................................................................... 64 6.2.3 Introduction of pollutants into waters ..................................................................... 64 6.2.4 Overwater shading and effects to prey.................................................................... 65 6.2.5 Loss of marine mammal habitat .............................................................................. 65 6.2.6 Indirect effects of increasing accessibility of Gravina Island ................................. 65 6.3 Stressors Likely to Adversely Affect ESA-listed Species ............................................. 65 6.3.1 Description of sound propagation ........................................................................... 65 6.3.2 Acoustic thresholds ................................................................................................. 66 6.4 Exposure Analysis .......................................................................................................... 68 6.4.1 Exposure to noise from pile driving activities ........................................................ 68 6.4.2 Exposure to vessel noise ......................................................................................... 74 6.5 Response Analysis.......................................................................................................... 74 6.5.1 Responses to major noise sources (pile driving/removal activities) ....................... 75 6.5.2 Probable responses to major noise sources (pile driving activities) ....................... 83 6.5.3 Responses to vessel traffic and noise ...................................................................... 83 6.5.4 Probable responses to vessel traffic and noise ........................................................ 86 6.6 Interrelated/Interdependent Effects ................................................................................ 86 7. Cumulative Effects................................................................................................................ 86 8. Integration and Synthesis ...................................................................................................... 87 8.1 Mexico DPS Humpback Whale Risk Analysis .............................................................. 87 9. Conclusion ............................................................................................................................ 88 10. Incidental Take Statement.................................................................................................. 88 10.1 Amount of Extent of Take .......................................................................................... 89 10.2 Effect of the Take ....................................................................................................... 90 10.3 Reasonable and Prudent Measures ............................................................................. 91 10.4 Terms and Conditions ................................................................................................. 91 11. Conservation Recommendations ....................................................................................... 92 12. Reinitiation of Consultation ............................................................................................... 92 13. Data Quality Act Documentation and Pre-dissemination Review ..................................... 93 13.1 Utility .......................................................................................................................... 93 13.2 Integrity ...................................................................................................................... 93 13.3 Objectivity .................................................................................................................. 93 14. References .......................................................................................................................... 95 3 Ketchikan Tongass Narrows Project PCTS AKR-2018-9806 LIST OF TABLES Table 1. Summary of Tongass Narrows Project phases and components. ................................... 12 Table 2. Summary of construction methods for each component in Phase 1 of the Tongass Narrows Project (HDR 2018a).....................................................................................................