Biological Opinion on U.S. Navy SURTASS LFA Sonar Activities 2019

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Biological Opinion on U.S. Navy SURTASS LFA Sonar Activities 2019 Biological Opinion on U.S. Navy SURTASS LFA Sonar Activities Consultation No. OPR-2019-00120 TABLE OF CONTENTS Page 1 Introduction ........................................................................................................................... 1 1.1 Background ...................................................................................................................... 2 1.2 Consultation History ........................................................................................................ 3 2 The Assessment Framework ................................................................................................ 5 2.1 Evidence Available for the Consultation ......................................................................... 8 2.1.1 Approach to Assessing Effects to Marine Mammals ................................................ 9 2.1.2 Approach to Assessing Effects to Sea Turtles ........................................................ 24 3 Description of the Proposed Action ................................................................................... 25 3.1 The Navy’s Proposed Action ......................................................................................... 26 3.2 Description of the Surveillance Towed Array Sensor System (SURTASS) Low Frequency Active (LFA) Sonar System ................................................................................... 28 3.2.1 Passive Sonar System Components ........................................................................ 29 3.2.2 Active Sonar System Components.......................................................................... 30 3.3 Vessel Specifications ...................................................................................................... 30 3.4 Mitigation and Monitoring ............................................................................................. 31 3.4.1 Operational Parameters ........................................................................................... 32 3.4.2 Mitigation/Buffer Zone ........................................................................................... 32 3.4.3 Ramp Up of High Frequency Marine Mammal Monitoring (HF/M3) ................... 33 3.4.4 Low Frequency Active Sonar Suspension/Delay ................................................... 33 3.4.5 Geographical Mitigation Measures ......................................................................... 33 3.4.6 Coastal Standoff Distance ....................................................................................... 35 3.4.7 Dive Sites ................................................................................................................ 35 3.4.8 Offshore Biologically Important Areas (OBIAs) ................................................... 35 3.4.9 Sound Field Modeling............................................................................................. 42 3.4.10 Visual Monitoring ................................................................................................... 42 3.4.11 Passive Acoustic Monitoring .................................................................................. 43 3.4.12 Active Acoustic Monitoring ................................................................................... 43 3.5 NMFS Permits and Conservation Division Proposed Actions....................................... 45 3.5.1 Promulgation of Regulations Pursuant to the Marine Mammal Protection Act 45 3.5.2 Issuance of a Letter of Authorization ...................................................................... 58 3.6 Action Area .................................................................................................................... 58 3.7 Interrelated and Interdependent Actions ........................................................................ 60 4 Potential Stressors ............................................................................................................... 60 4.1 Acoustic Disturbance ..................................................................................................... 60 4.1.1 Vessel Noise............................................................................................................ 60 4.1.2 LFA Sonar ............................................................................................................... 68 i Biological Opinion on U.S. Navy SURTASS LFA Sonar Activities Consultation No. OPR-2019-00120 4.1.3 HF/M3 sonar ........................................................................................................... 68 4.2 Vessel Strike ................................................................................................................... 69 4.3 Vessel Discharge ............................................................................................................ 72 4.4 Entanglement .................................................................................................................. 72 5 Species and Critical Habitat Not Likely to be Adversely Affected ................................ 73 5.1 Endangered Species Act- Listed Cetaceans ................................................................... 76 5.2 Endangered Species Act-Listed Salmonids .................................................................... 78 5.3 Endangered Species Act-Listed Sturgeon ...................................................................... 81 5.4 Endangered Species Act-Listed Elasmobranchs ............................................................ 82 5.5 Hawaiian Monk Seal Critical Habitat ............................................................................ 84 5.6 Critical Habitat for the Main Hawaiian Islands Insular Distinct Population Segment of the False Killer whale ............................................................................................ 87 6 Status of Endangered Species Act-Listed Species Likely to be Adversely Affected by the Proposed Action .................................................................................................................... 91 6.1 Blue Whale ..................................................................................................................... 93 6.2 Fin Whale ....................................................................................................................... 99 6.3 Gray Whale – Western North Pacific Population ........................................................ 103 6.4 North Pacific Right Whale ........................................................................................... 106 6.5 Sei Whale ..................................................................................................................... 111 6.6 Humpback Whale – Western North Pacific Distinct Population Segment .................. 114 6.7 False Killer Whale – Main Hawaiian Islands Insular Distinct Population Segment .................................................................................................................................. 118 6.8 Sperm Whale ................................................................................................................ 121 6.9 Hawaiian Monk Seal .................................................................................................... 126 6.10 Spotted Seal – Southern Distinct Population Segment ................................................ 129 6.11 Steller Sea Lion – Western Distinct Population Segment ............................................ 132 6.12 Green Turtle – Central North Pacific Distinct Population Segment ............................ 137 6.13 Green Turtle – East Indian – West Pacific Distinct Population Segment .................... 141 6.14 Green Turtle – North Indian Distinct Population Segment .......................................... 144 6.15 Green Turtle - Central West Pacific Distinct Population Segment .............................. 147 6.16 Hawksbill Turtle ........................................................................................................... 151 6.17 Leatherback Turtle ....................................................................................................... 154 6.18 Loggerhead Turtle – North Indian Ocean Distinct Population Segment ..................... 159 6.19 Loggerhead Turtle – North Pacific Ocean Distinct Population Segment .................... 162 6.20 Loggerhead Turtle – Southeast Indo-Pacific Ocean Distinct Population Segment ..... 165 6.21 Olive Ridley Turtle....................................................................................................... 168 7 Environmental Baseline ................................................................................................... 172 7.1 Climate Change ............................................................................................................ 172 7.2 Oceanic Temperature Regimes .................................................................................... 175 ii Biological Opinion on U.S. Navy SURTASS LFA Sonar Activities Consultation No. OPR-2019-00120 7.3 Disease ......................................................................................................................... 177 7.4 Invasive Species ........................................................................................................... 178 7.5 Pollution ....................................................................................................................... 179 7.5.1 Marine
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