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Quintillion 2016 Subsea Cable System

Phase 1 Installation Program Marine Mammal Monitoring and Mitigation

90-Day Report

February 2017

Prepared for:

Quintillion Subsea Operations, LLC 201 East 56th Avenue, #300 Anchorage, Alaska 99518

Prepared by:

Owl Ridge Natural Resource Consultants, Inc. 6407 Brayton Drive, Suite 204 Anchorage, Alaska 99507 T: 907.344.3448 F: 907.344.3445 www.owlridgenrc.com

90-DAY REPORT

MARINE MAMMAL MONITORING AND MITGATION DURING PHASE 1 INSTALLATION PROGRAM FOR SUBSEA CABLE BY QUINTILLION SUBSEA OPERATIONS, LLC IN THE

BERING, BEAUFORT, AND CHUKCHI SEAS 2016

Prepared by:

Megan Blees, Gregory Green, and Paul Cartier

Owl Ridge Natural Resource Consultants, Inc. 6407 Brayton Drive, Suite 204

Anchorage, AK 99507

For:

Quintillion Subsea Operations, LLC 201 E. 56th Avenue, Suite 300

Anchorage, Alaska 99518

National Marine Fisheries Service, Office of Protected Resources 1315 East-West Highway

Silver Springs, MD 20910

U.S. Fish and Wildlife Service, Marine Mammal Management 1101 E. Tudor Road, M.S. 341

Anchorage, AK 99503

February 2017

Quintillion Subsea Operations, LLC Phase I Installation Program Marine Mammal Monitoring and Mitigation 90-Day Report

ACKNOWLEDGEMENTS

The marine mammal monitoring program was managed by Megan Blees with project and field assistance from Greg Green, Greg Fulling, Myra Fernandez, Cassandra Strodtman, Nathan Anderson, Paul Cartier, Cara Wright, and Glenn Ruckhaus. PSOs included Ken Patrick, Jonah Leavitt, Layne Olson, Amanda Stafford, Forrest Ahkiviana, Brad Dawe, Kristine Lindberg, Sean Schenkenberger, Greg Sagmeister, and Taylor Sullivan. Megan Blees and Greg Green authored this 90-day report. Paul Cartier conducted the GIS analyses and developed the figures.

The sound source verification (SSV) was conducted by Keith Pommerenck with Illingworth & Rodkin (I&R). James Reyff with I&R assisted with the acoustical analysis and reporting.

To meet passive acoustical monitoring (PAM) obligations required by the Incidental Harassment Authorizations (IHAs), Quintillion Subsea Operations (Quintillion) provided funding to the Arctic Long-Term Integrated Mooring Array (ALTIMA) project, a passive acoustical program conducted by the University of Washington Joint Institute for the Study of the Atmosphere and Ocean (JISAO) and the NMFS Marine Mammal Laboratory (NMML). In exchange, the ALTIMA project provided acoustical data and analysis of underwater sounds produced by the cable-lay activities as they passed by the moored acoustical recorders, as well as data on marine mammal vocalizations. In addition, Quintillion funded the Native Village of Kotzebue to deploy two acoustic moorings within Kotzebue Sound and analyze the collected data. Manuel Castellote with JISAO led both projects with assistance from Catherine Berchok and Jessica Crance with NMML, Stephanie Grassia with JISAO, and Alex Whiting with the Village of Kotzebue.

Owl Ridge Natural Resource Consultants, Inc. (Owl Ridge) appreciates the support from Quintillion, especially Elizabeth Pierce, Kristina Wolston, Frank Cuccio, the Viking ice advisors, Edith Vorderstrasse, and the community liaisons in each landing community. Additionally, gratitude is extended to the cable vessel crews and project representatives onboard the Ile de Brehat, Ile de Sein, CB Networker, and Swissco 48.

All project work, including this report, was supported by Quintillion.

Suggested citation:

Blees, M.K., G.A. Green, and P. Cartier. 2017. Quintillion 2016 Subsea Cable System Phase 1 Installation Program: Marine Mammal Monitoring and Mitigation 90-Day Report. Prepared by Owl Ridge Natural Resource Consultants, Inc. for Quintillion Subsea Operations, LLC, National Marine Fisheries Service, and U.S. Fish and Wildlife Service. 58 pp. + Appendices.


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TABLE OF CONTENTS

Acronyms and abbreviations ..................................................................................................................... v

1. Introduction and Background ............................................................................................................. 1 1.1. Authorizations .............................................................................................................................. 1 1.2. Monitoring and Mitigation Objectives ......................................................................................... 2 1.3. 90-Day Report Organization ........................................................................................................ 3

2. Subsea Cable Installation Operations ................................................................................................ 4 2.1. Project Details .............................................................................................................................. 4

Cable Network ................................................................................................................... 4 Vessels ............................................................................................................................... 4 Pre-Lay Grapnel Run ......................................................................................................... 6 Cable-Lay Operations ........................................................................................................ 6 Ice Management ................................................................................................................ 7 Post-Lay Inspection and Burial ......................................................................................... 8

2.2. Acoustical Sources ....................................................................................................................... 8

3. Sound Source Verification and Passive Acoustic Monitoring .......................................................... 9 3.1. Sound Source Verification ........................................................................................................... 9 3.2. Passive Acoustical Monitoring .................................................................................................. 10

ALTIMA .......................................................................................................................... 11 Marine Mammal Detections ............................................................................................ 12 Kotzebue .......................................................................................................................... 13

4. Marine Mammal Monitoring Implementation ................................................................................ 15 4.1. Harassment Zones ...................................................................................................................... 15 4.2. Methods...................................................................................................................................... 16

Monitoring Methods ........................................................................................................ 16 Analysis Methods ............................................................................................................ 17

5. Marine Mammal Monitoring Results ............................................................................................... 20 5.1. Protected Species Observer Effort ............................................................................................. 20

PSO Effort by Watch Status ............................................................................................ 20 On-Watch PSO Effort by Area ........................................................................................ 21 On-Watch PSO Effort in the Project Area by Vessel Noise Activity .............................. 21 On-Watch PSO Effort in the Project Area by Sea State .................................................. 22 Usable PSO Effort ........................................................................................................... 23

5.2. Marine Mammals Recorded ....................................................................................................... 26 Cetaceans ......................................................................................................................... 27 Pinnipeds (Excluding Pacific Walrus) ............................................................................. 38 Pacific Walrus ................................................................................................................. 45 Polar Bears ....................................................................................................................... 52


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Carcasses ......................................................................................................................... 53 5.3. Animals Potentially Affected ..................................................................................................... 54

Cetaceans ......................................................................................................................... 54 Pinnipeds ......................................................................................................................... 54 Walrus.............................................................................................................................. 55 Polar Bear ........................................................................................................................ 55

5.4. Summary and Conclusions......................................................................................................... 55

6. Literature Cited .................................................................................................................................. 57

List of Tables Table 2-1. Network Route Lengths for Each Segment ................................................................................. 4 Table 4-1. Harassment Zones Monitored by the PSOs during the 2016 Operations .................................. 15 Table 4-2. Dates (2016) PSOs Boarded and Disembarked each Vessel ..................................................... 16 Table 4-3. Ensonification Zones for Vessel Activities ............................................................................... 19 Table 5-1. On-Watch PSO Effort by Vessel Activity within the Project Area ........................................... 22 Table 5-2. Total On-Watch PSO Effort and Usable PSO Effort ................................................................. 23 Table 5-3. Cetacean Groups (Individuals) Observed from all Cable Vessels within the Project Area ....... 28 Table 5-4. Cetacean Groups (Individuals) Observed from all Cable Vessels within the Project Area by Sea State ............................................................................................................................................................ 30 Table 5-5. Cetacean Groups (Individuals) Observed from All Cable Vessels within the Project Area by Vessel Noise Activity ................................................................................................................................. 31 Table 5-6. Cetacean Groups (Individuals) Observed from All Cable Vessels within the Project Area by Closest Distance to Vessel .......................................................................................................................... 32 Table 5-7. Cetacean Groups (Individuals) Observed from All Cable Vessels within the Project Area by Behavior ...................................................................................................................................................... 33 Table 5-8. Cetacean Groups (Individuals) Observed from All Cable Vessels within the Project Area by Reactionary Behavior .................................................................................................................................. 34 Table 5-9. Pinniped Groups (Individuals) Observed from All Cable Vessels within the Project Area ...... 38 Table 5-10. Pinniped Groups (Individuals) Observed from All Cable Vessels within the Project Area by Sea State ...................................................................................................................................................... 39 Table 5-11. Pinniped Groups (Individuals) Observed from All Cable Vessels within the Project Area by Vessel Noise Activity ................................................................................................................................. 39 Table 5-12. Pinniped groups (Individuals) Observed from All Cable Vessels within the Project Area by Closest Distance to Vessel .......................................................................................................................... 40 Table 5-13. Pinniped Groups (Individuals) Observed from All Cable Vessels within the Project Area by Behavior ...................................................................................................................................................... 40 Table 5-14. Pinniped Groups (Individuals) Observed from All Cable Vessels within the Project Area by Reactionary Behavior .................................................................................................................................. 41 Table 5-15. Walrus groups (Individuals) Observed from All Cable Vessels within the Project Area ....... 45 Table 5-16. Walrus Groups (Individuals) Observed from All Cable Vessels within the Project Area by Sea State ............................................................................................................................................................ 46 Table 5-17. Walrus Groups (Individuals) Observed from All Cable Vessels within the Project Area by Vessel Noise Activity ................................................................................................................................. 46 Table 5-18. Walrus Groups (Individuals) Observed from All Cable Vessels within the Project Area by Closest Distance to Vessel .......................................................................................................................... 47 Table 5-19. Walrus Groups (Individuals) Observed from All Cable Vessels within the Project Area by Behavior ...................................................................................................................................................... 47


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Table 5-20. Walrus Groups (Individuals) Observed from All Cable Vessels within the Project Area by Reactionary Behavior .................................................................................................................................. 47 Table 5-21. Polar Bear Groups (Individuals) Observed from All Cable Vessels within the Project Area. 52 Table 5-22. Polar Bear Groups (Individuals) Observed from All Cable Vessels within the Project Area by Vessel Noise Activity ................................................................................................................................. 53 Table 5-23. Carcasses (Individuals) Recorded per Vessel .......................................................................... 54 Table 5-24. Cetaceans (Individuals) Potentially Exposed to Sound Levels Exceeding 120 dB ................. 54 Table 5-25. Pinnipeds (Individuals) Potentially Exposed to Sound Levels Exceeding 120 dB ................. 55

List of Figures Figure 1-1. Quintillion Subsea Fiber Optic Cable Network ......................................................................... 2 Figure 2-1. Transit Route from Dutch Harbor, Critical Habitat, and the General Project Area ................... 5 Figure 2-2. Cable Ships Ile de Brehat (Left) and Ile de Sein (Right) ........................................................... 6 Figure 2-3. Cable Barges CB Networker (LEFT) and Swissco 48 (Right) ................................................... 6 Figure 2-4. SMD Heavy Duty HD3 Plow Onboard the Ile de Brehat .......................................................... 7 Figure 2-5. ROVJET 400 Series ................................................................................................................... 8 Figure 3-1. Locations of PAM Moorings Analyzed for Marine Mammal Vocalizations and Cable-Lay Underwater Sound Levels ........................................................................................................................... 11 Figure 5-1. On-Watch PSO Effort within the Transit and Project Areas by Month ................................... 20 Figure 5-2. PSO Effort in both the Transit and Project Area by Watch Status ........................................... 21 Figure 5-3. Usable PSO Effort in the Project Area by Sea State ................................................................ 23 Figure 5-4. Usable PSO Effort in the Project Area by Precipitation Type ................................................. 24 Figure 5-5. Usable PSO Effort in the Project Area by Visibility ................................................................ 24 Figure 5-6. Usable PSO Effort in the Project Area by Percent Ice Coverage ............................................. 25 Figure 5-7. Usable PSO Effort within the Project Area by Speed Class .................................................... 26 Figure 5-8. Total Sightings for all Cable Vessels within the Project Area ................................................. 27 Figure 5-9. Photo of Humpback Whales taken August 17, 2016 from the Ile de Brehat ........................... 29 Figure 5-10. Cetacean Sighting Rates by Vessel Noise Activity ................................................................ 34 Figure 5-11. Cetacean Sighting Rates by Sea State .................................................................................... 35 Figure 5-12. Cetacean Sighting Rates by Precipitation .............................................................................. 36 Figure 5-13. Cetacean Sighting Rates by Visibility .................................................................................... 36 Figure 5-14. Cetacean Sighting Rates by Ice Coverage .............................................................................. 37 Figure 5-15. Cetacean Sighting Rates by Speed Class ............................................................................... 37 Figure 5-16. Pinniped Sighting Rates by Vessel Noise Activity ................................................................ 42 Figure 5-17. Pinniped Sighting Rates by Sea State .................................................................................... 42 Figure 5-18. Pinniped Sighting Rates by Precipitation ............................................................................... 43 Figure 5-19. Pinniped Sighting Rates by Visibility .................................................................................... 44 Figure 5-20. Pinniped Sighting Rates by Ice Coverage .............................................................................. 44 Figure 5-21. Pinniped Sighting Rates by Speed Class ................................................................................ 45 Figure 5-22. Pacific Walrus Sighting Rates by Vessel Noise Activity ....................................................... 49 Figure 5-23. Pacific Walrus Sighting Rates by Sea State ........................................................................... 49 Figure 5-24. Pacific Walrus Sighting Rates by Precipitation ..................................................................... 50 Figure 5-25. Pacific Walrus Sighting Rates by Visibility ........................................................................... 51 Figure 5-26. Pacific Walrus Sighting Rates by Ice Coverage ..................................................................... 51 Figure 5-27. Pacific Walrus Sighting Rates by Speed Class ...................................................................... 52

Quintillion Subsea Operations, LLC Phase I Installation Program Marine Mammal Monitoring and Mitigation

90-Day Report

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Appendices

APPENDIX A – Incidental Harassment Authorizations

APPENDIX B – Vessel Specifications

APPENDIX C – Sound Source Verification Report

APPENDIX D – Passive Acoustic Monitoring Report

APPENDIX E – Beaufort Sea State Scale

APPENDIX F – Marine Mammal Behavior and Reaction Descriptions

APPENDIX G – Marine Mammal Sighting Data

APPENDIX H – Vessel Track and Marine Mammal Sighting Maps

APPENDIX I – Carcass Reports

Appendices are available upon requestcall 907-786-3800


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ACRONYMS AND ABBREVIATIONS

4MP .................. Marine Mammal Monitoring and Mitigation Plan AHT ................. anchor-handling tug ALTIMA .......... Arctic Long-Term Integrated Mooring Array ASL .................. above sea level ASN ................. Alcatel-Lucent Submarine Networks BMH ................ beach man hole BU .................... branching unit CPA .................. closest point of approach dB ..................... decibel(s) DP .................... dynamic positioning ft ....................... foot/feet h ....................... hour(s) HDD ................. Horizontal Directionally Drilled IHA .................. Incidental Harassment Authorization I&R .................. Illingworth & Rodkin JISAO ............... Joint Institute for the Study of the Atmosphere and Ocean (University of Washington) Kt ..................... knot(s) km .................... kilometer(s) kW .................... kilowatt LOG ................. Letter of Guidance m ...................... meter(s) mi ..................... (s) min……………minute(s) MMPA ............. Marine Mammal Protection Act NMFS ............... National Marine Fisheries Service NMML ............. NMFS Marine Mammal Laboratory PAM ................. passive acoustic monitoring PLGR ............... Pre-Lay Grapnel Run PSO .................. Protected Species Observer PTS…………...permanent threshold shift re 1µ Pa ............ relative to 1 micro Pascal rms ................... root mean square ROV ................. remotely operated vehicle SPL…………...sound pressure level SSV .................. sound source verification USFWS ............ U.S. Fish and Wildlife Service


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1. INTRODUCTION AND BACKGROUND

Quintillion Subsea Operations, LLC (Quintillion), proposed to install a subsea fiber-optic cable network (the project) along the northern and western coasts of Alaska to provide high speed internet connectivity to five rural Alaska communities and an industrial site (Oliktok Point). Once completed, the subsea fiber-optic cable network will link with an existing North Slope terrestrial‐based fiber-optic line. The Quintillion project will consist of over 1,900 kilometers (km) (1,180 miles [mi]) of fiber-optic cable including a main trunk line and six branch lines to onshore facilities in Nome, Kotzebue, Point Hope, Wainwright, Barrow, and Oliktok Point (Figure 1-1). About 96% of the subsea cable was installed by Alcatel-Lucent Submarine Networks (ASN) in 2016 (the remaining 76 km [47 mi] of route is planned to be installed during the 2017 open water season).

The cable-lay ships, cable-lay barges, and support tugs employed for the Project use drive propellers and thrusters for propulsion, dynamic positioning (DP), and anchor-handling during cable-lay operations. The noise generated by these sources has a potential for acoustically harassing marine mammals, a form of “take” as defined under the Marine Mammal Protection Act (MMPA), and thus are subject to governance under the MMPA. Incidental and unintentional harassment takes are permitted with the issuance of Incidental Harassment Authorizations (IHAs) from the National Marine Fisheries Service (NMFS) and U.S. Fish and Wildlife Service. Quintillion received IHAs from both agencies, both of which stipulate that Quintillion monitor for marine mammals during the cable-lay activities and report the results of the monitoring program within 90 days of activity completion. Owl Ridge Natural Resource Consultants, Inc. (Owl Ridge) prepared this document which comprises the required 90-day report and includes results of the associated sound source verification (SSV) study and passive acoustical monitoring (PAM) program.

1.1. Authorizations On May 31, 2016, Quintillion received an IHA from NMFS authorizing acoustical harassment of 12 marine mammal species under the jurisdiction of NMFS. An amended IHA was received by Quintillion September 27, 2016 which added Steller sea lions to the list of authorized species, and increased the number of humpback whales that could be harassed. The IHA was amended to account for the unexpected presence of these two “subarctic” species. A third amendment was received October 21, 2016, extending the IHA validation period from October 31, 2016 to November 15, 2016. This allowed Quintillion to conduct operations in November while the project area remained ice-free.

Because of processing issues, the USFWS was not able to provide Quintillion an IHA until August 11, 2016. However, on May 27, 2016 the USFWS did provide a letter of guidance (LOG) that provided means for Quintillion to avoid and minimize take of Pacific walrus. Further, all cable-lay operations prior to August 11 were confined to Norton Sound, and no walruses were recorded. Polar bears were not included in the USFWS IHA because, given the location and timing of activities, and the inherent project avoidance of sea ice, polar bears were not expected to be encountered in a situation that would lead to harassment take (and none were taken).

All original and amended IHAs are provided in Appendix A.



Figure 1-1. Quintillion Subsea Fiber Optic Cable Network

1.2. Monitoring and Mitigation Objectives The purpose of this 90-day report is 1) describe Quintillion 2016 cable-lay activities in the Bering, Chukchi, and Beaufort seas; 2) describe the methodology and results of the marine mammal monitoring program; 3) estimate the number of marine mammals potentially exposed to underwater noise levels exceeding thresholds for harassment take; and 4) present the results from the SSV study and PAM program.

As stipulated in the IHAs, a vessel-based marine mammal monitoring program was implemented. The specific objectives of the monitoring program were to:

• ensure disturbance to marine mammals is minimized and all permit stipulations are followed

• document effects of the cable-lay activities on marine mammals

• collect data on the occurrence and distribution of marine mammals in the project area.

These objectives were met by implementing an agency-approved Marine Mammal Monitoring and Mitigation Plan (4MP) using a team of experienced Protected Species Observers (PSOs), including both biologists and native (Inupiat/Yupik) observers. The PSOs conducted visual marine mammal observations from two cable-lay ships (Ile de Brehat and Ile de Sein) and two cable-lay barges (CB Networker and Swissco 48) and implemented mitigation (e.g., speed reduction, course alteration) when necessary.



The vessel-based observations provided:

• the basis for real-time mitigation, if necessary, as required by the IHA

• information needed to estimate the number of “Level B takes” of marine mammals by harassment, which must be reported to NMFS and USFWS

• data on the occurrence, distribution, and activities of marine mammals in the areas where the cable-lay operations are conducted

• information to compare the distances, distributions, behavior, and movements of marine mammals relative to the source vessels at times with and without cable-lay activity.

In addition to conducting visual observations, the local native PSOs also provided a communication channel to coastal subsistence communities, including Inupiat/Yupik hunters, as needed. Quintillion supports providing employment opportunities for local residents and development/experience for local PSOs.

1.3. 90-Day Report Organization This report was developed to meet the requirements specified in the NMFS and USFWS IHAs and includes the following sections:

1. Background and Introduction (this section)

2. Subsea Cable Installation Operations

3. Sound Source Verification and Passive Acoustic Monitoring

4. Marine Mammal Monitoring Implementation

5. Marine Mammal Monitoring Results.

6. Literature Cited

In addition to the report sections, this document has nine appendices to provide background material and additional information to supplement the report. The appendices are:

A. Incidental Harassment Authorizations

B. Vessel Specifications

C. Sound Source Verification Report

D. Passive Acoustic Monitoring Report

E. Beaufort Sea State Definitions

F. Marine Mammal Behavior and Reaction Descriptions

G. Marine Mammal Sighting Data

H. Vessel Tracks and Marine Mammal Sighting Maps

I. Carcass Report



2. SUBSEA CABLE INSTALLATION OPERATIONS

2.1. Project Details The cable-lay ships (cable ships) (Ile de Brehat and Ile de Sein) transited to the project area from Dutch Harbor, whereas the cable-lay barges (cable barges) (CB Networker and Swissco 48) were transported via heavy-lift barge and mobilized at Nome prior to project operations. Figure 2-1 depicts the transit route (approximately 1,288 km [800 mi]) of the cable-lay ships as well as the area defined as the “Project Area,” which includes all project activities north of 64° North (N).

Cable Network

Lengths of each cable segment (trunk line and branches) are listed Table 2-1. Branching lines range between 27 km (17 mi) and 233 km (145 mi). Branching lines connect to the main trunk line at the branching unit (BU), which is a piece of hardware that allows the interconnection of the branching cable from the main trunk line to the shore-end facility. The cable signal is amplified through a repeater attached to the cable approximately every 76 km (47 mi). Collectively, the cable, BUs, and repeaters make up the “submerged plant”. Depending on the bottom substrate, water depth, and distance from shore, the cable was either laid on the ocean floor or buried using a sea plow, injector, or remotely operated vehicle (ROV) equipped for burial by water jetting.

Table 2-1. Network Route Lengths for Each Segment

Route Length

Segment (km)

Total Main

Branch Lines Oliktok Barrow Wainwright Point Hope Kotzebue Nome

1297 96 27 31 27 233 195 1904

Vessels

The offshore waters (>12 meters [m] deep; >39 feet [ft]) cable-lay operations were conducted from the sister cable-lay ships Ile de Brehat and Ile de Sein (Figure 2-2). The vessels were 140 m (460 ft) in length, 23 m (77 ft) in breadth, and could each support a crew of 70. The ships were propelled by two 4,000-kilowatt (kW) fixed-pitch propellers. Dynamic positioning is maintained by two 1,500-kW bow thrusters, 1,500-kW aft thrusters, and one 1,500 kW-fore thruster. The full specifications of the ships are provided in Appendix B.

The shallow waters (<12 m deep; < 39 ft deep) cable-lay operations were conducted by two cable barges, CB Networker and Swissco 48 (Figure 2-3). Full specifications of each vessel are provided in Appendix B. During cable-lay operations, the cable barges set anchors and winched along the anchor lines for propulsion along the cable route. Although both cable barges were capable of operating under their own power, each had a support anchor-handling tug (AHT) that assisted the barges for towing and handling or repositioning anchors. The AHT Vos Thalia assisted the CB Networker and the smaller AHT Dana Cruz assisted the Swissco 48. For the purposes of this report, we consider the operations conducted by either tug or barge as a single unit, unless otherwise specified.



Figure 2-1. Transit Route from Dutch Harbor, Critical Habitat, and the General Project Area



Figure 2-2. Cable Ships Ile de Brehat (Left) and Ile de Sein (Right)

The CB Networker conducted operations on the nearshore segments at Nome, Wainwright, and Oliktok, and the Swissco 48 operated at Point Hope, Barrow, and Kotzebue.

Figure 2-3. Cable Barges CB Networker (LEFT) and Swissco 48 (Right)

Pre-Lay Grapnel Run

Before cable was laid, a pre-lay grapnel run (PLGR) was conducted along the cable route by a local vessel, MV Discovery, to identify and clear any preexisting seabed debris (e.g., wires, fishing gear). This vessel did not have berths to accommodate PSOs, and is not further discussed in this report.

Cable-Lay Operations

The objective of the offshore “surface” cable-lay operation (on the seafloor, not buried) was to install the cable as close as possible to the planned route with the correct amount of cable slack to enable the cable to conform to the contours of the seabed without loops or suspensions. A slack plan was developed that used direct bathymetric data and a catenary modeling system to control the ship and the cable pay out speeds to ensure the cable was accurately placed in its planned physical position.



To avoid conflict with fishing activity (e.g., fishing vessels snagging the cable), all cable in waters south of the Bering Strait were buried beneath the seafloor. In addition, cable was buried in all waters <50 m (<164 ft) deep to protect it from ice scour (cable was laid directly on the seafloor only in the Chukchi and Beaufort seas where water depths were >50 m [164 ft]). In water depths between 12 m (40 ft) and 50 m (164 ft), the cable was buried beneath the seafloor using a SMD Heavy Duty HD3 plow (Figure 2-4) deployed from the cable ships (Ile de Brehat and Ile de Sein).

Figure 2-4. SMD Heavy Duty HD3 Plow Onboard the Ile de Brehat

In water depths less than 12 m (40 ft), cable burial was accomplished by using a variety of methods determined by seabed conditions: water-jet burial using a towed sled (Swissco 48), water-injector burial (CB Networker), or diver jet/air-lift burial (Swissco 48 and CB Networker). At each beach landing, a pulling wire from the beach was preinstalled through a horizontal directionally drilled (HDD) boring and fastened to the end of the cable on the barge. A beach winch was used to haul the pulling wire and fiber optic cable back through the HDD boring to the beach manhole (BMH) where it was anchored to the BMH and the fiber optic cable spliced to the terrestrial cable. Each cable barge used a type of water-jetting tool, or sled, to create a trench in the seafloor for cable installation. This operation was performed from a point near the end of the HDD boring to the end of the shore-end cable where it was picked up and spliced, then continued offshore by a cable ship. Cable burial in the gap between the end of the HDD boring and the start of the burial sled was accomplished by divers using a combination of air-lift and water-jetting tools.

Ice Management

The project was planned to avoid the presence of ice and to allow continuous safe operations. Any presence of ice during installation had the potential to damage or sever the cable. Despite the planning, ice was occasionally present during cable-lay operations in 2016 and required some management or evasive actions. Support vessels did conduct minimal ice management to steer ice around the cable-lay operations. If the support vessels and PSO verified no marine mammals were hauled out on the ice, the tugs would contact the floe and slowly maneuver it away from cable-lay operations. If the situation could not be easily and



safely managed, the cable ships conducted evasive action, which in some cases included intentional severing of the cable.

Post-Lay Inspection and Burial

The Ile de Brehat conducted the post-lay inspection and burial (PLIB) at the BUs along the route for approximately three weeks (late October to early November). BUs and cable splices cannot be buried by the plow, so the intent of the PLIB is to use the ROV (ROVJET 400 series) (Figure 2-5) to bury the BUs and associated exposed cable. The ROV is 5.8 m (19 ft) long and 3.4 m (11.2 ft) wide and weighs 9.1 tonnes (10 tons), and has both a main and forward jet tool capable of trenching to 2 m (6.6 ft) depth. To prevent ice scour, the Ile de Brehat also placed up to four 6 m x 3 m (19.6 ft x 9.8 ft) concrete mattresses over three branching units (Nome, Point Hope, and Wainwright). Not all PLIB operations were completed in 2016. The remaining PLIB effort is planned to be conducted in 2017.

Figure 2-5. ROVJET 400 Series

2.2. Acoustical Sources The cable ships, cable barges, and support tugs use thrusters for DP and anchor handling during cable-lay operations. Additionally, the vessels generate cavitation with drive propellers when pulling sea plows used to install cable, the barges generate noise when winching and using water-jetting tools to trench for the cable-lay operation, and tugs associated with the barges generate noise when operating thrusters to pull and reset barge anchors. The noises generated by these sources may potentially harass marine mammals, considered a “take” under the MMPA, and thus were permitted via IHAs from NMFS and USFWS. Measurements of these sound sources are discussed in Section 3.



3. SOUND SOURCE VERIFICATION AND PASSIVE ACOUSTIC MONITORING

During the IHA application process, Quintillion agreed to conduct a SSV of both ship and barge cable-lay operations to more accurately evaluate the area ensonified by these operations and develop project-specific marine mammal monitoring zones. Quintillion also agreed to fund two PAM projects designed to acoustically measure the underwater soundscape and marine mammal vocal activity before, during, and after cable-lay operations passed by the moored underwater recorders. Details of the SSV and PAM programs are described below. The full reports are provided in Appendix C (SSV; Pommerenck and Reyff 2016) and Appendix D (PAM; Castellote et al. 2017).

3.1. Sound Source Verification Quintillion contracted I&R to conduct SSV of the cable barge CB Networker and the cable ship Ile de Brehat as both began seasonal operations near Nome. The CB Networker’s mission was to lay 2.5 km (1.6 mi) of cable in the nearshore waters off Nome, where water depth is too shallow for large cable ship operation. The Ile de Brehat crew would then later splice the cable to the end of the nearshore section and continue laying cable along the Nome branch, farther offshore to the mainline route. Barge- and ship cable laying were not planned to occur simultaneously, so the intent was for I&R to make two trips to Nome while each vessel was close enough to Nome to safely access activities from a small locally contracted fishing boat (9-m [30-ft] Golovin Bay). However, weather conditions (high winds) prevented both cable-lay and SSV activities from occurring during the first trip by I&R. Sounds from both the barge and ship were finally measured during the second trip (in total, I&R acousticians were on weather standby for 10 days in Nome waiting for conditions to improve). I&R also intended to measure thruster noise from the AHT Vos Thalia while it was retrieving anchors for the CB Networker. However, the CB Networker was able to retrieve its own anchors using a crane during the small window I&R was able to measure barge activities. The Vos Thalia remained idle the entire measurement period.

Specific methodology used to collect SSV data is described by I&R in the SVV report (Appendix C). In general, the SSV procedure used suspended hydrophones to collect spot measurements from the Golovin Bay as the boat drifted away from the barge or ship. Data were also collected from two autonomous hydrophones anchored at fixed distances from the barge. Seas were too rough for successfully deploying or retrieving the autonomous recorders when measuring underwater sound emanating from the Ile de Brehat.

At the time of measurement, the CB Networker was conducting multiple activities, often simultaneously, including winching, operating the injector trenching tool, and pulling its own anchor with a crane. Activity was interspersed with periods of idleness. For safety reasons due to weather, individual activities could not be simply turned on and off to isolate sound signatures, thus data are presented based on the loudest sound signatures. The loudest sounds occurred when the barge was winching and operating the injector simultaneously.

Based on a regression curve of the measurements taken at distances ranging between 110 m and 2,100 m (361 ft and 6,890 ft), I&R estimated the 1-m source sound pressure level (SPL) as 181.77 decibels (dB)

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relative to (re) 1 microPascal (μPa) root mean square (rms) and the transmission loss at 19.83 Log R. The near spherical spreading loss may have been due to the shallow water in which the barge worked. The estimated distance to the 120-dB threshold for continuous noise impacts to marine mammals is 1.225 km (0.76 mi). The distance to the 160-dB isopleth (harassment threshold for walrus) was about 13 m (43 ft), while the distances to permanent threshold shift (PTS) hearing loss would occur, defined as Level A injury take, was <1 m for all species hearing groups.

The Ile de Brehat was measured while laying cable using a sea plow to dig a furrow into which the trailing cable is laid. To maintain its position accurately along the route, the Ile de Brehat used thrusters in addition to the main drive propeller. Prior to the SSV measurements, it was presumed that the thrusters would be the primary noise source based on previous measurements of thruster operations and previous sea plow operations conducted by Alcatel-Lucent. However, the seafloor near Nome (and elsewhere in the project area) proved to be considerably resistant requiring additional power (from a normal 40% to 80%) to effectively pull the trenching plow. The result was that cavitation noise emanating from the drive propeller contributed as much, if not more, to the noise signature as the thrusters.

Based on ten spot measurements that ranged between 200 m (656 ft) and 4.9 km (3.0 mi) from the ship, I&R estimated the source level at 185.2 dB re 1 μPa (rms) with a transmission loss function of 17.36 Log R. The estimated distance to the 120-dB threshold was 5.35 km (3.32 mi). The estimated distance to the 160-dB threshold was 20 m (66 ft), and distance to where PTS would occur was <4 m (13 ft) for all species hearing groups.

Safety concerns precluded isolating specific sound sources such as various thruster or drive propeller operations, as wind conditions dictated that power sources remain operating simultaneously. Attempts were made to measure transducer and echo sounder sound levels, but none of these sources were detected, presumably because their sound energy was focused downward under the vessel, and not horizontally towards the hydrophones.

3.2. Passive Acoustical Monitoring Conducting an effective PAM program for a linear operation, where the sound sources are constantly moving away from moored receivers, is difficult and very expensive. Receiver moorings would have to be constantly repositioned ahead of the cable-lay operations, necessitating the use of extraneous (noise-producing) vessels of a size sufficient to allow them to remain at sea, and near the cable fleet, during Arctic storm conditions. However, before the 2016 cable-lay operations, the NMML and the University of Washington JISAO, had already placed multiple PAM moorings near the proposed cable routes as part of their ALTIMA project. Quintillion contracted the NMML and JISAO to retrieve acoustical data from these moorings and analyze them for marine mammal vocalizations and underwater sound associated with the cable-lay operations. In addition, Quintillion contracted with the Native Village of Kotzebue to place two low-profile moorings in Kotzebue Sound to collect cable-lay operations sound data in the shallow water near the Kotzebue beach landing. Placing these moorings effectively extended for another year a Kotzebue Sound acoustical monitoring program jointly conducted by the village, JISAO, and the Alaska Department of Fish and Game. Both PAM programs are addressed in the report (Castellote et al. 2017) provided in Appendix D, and summarized in the subsections below.

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ALTIMA

Six long-term moorings were selected for analysis based on their proximity to the cable routes (distances ranged from 4.7 to 15.5 km [2.9 to 9.6 ft] from the routes) and potential vessel transit pathways. Because of the timing of data retrieval (September 2016), only three of the mooring receivers contained cable-lay operations acoustical data. These include moorings NM1 (Norton Sound) approximately 150 km (93 mi) offshore of Nome, KZ1 (Kotzebue Sound) approximately 260 km (162 mi) offshore of Kotzebue, and WT1 (Wainwright) approximately 48 km (30 mi) offshore of Wainwright (Figure 3-1). At the time of data retrieval, the cable-lay operations had not yet passed by the remaining three moorings. Data from these three moorings (offshore Cape Lisburne [CL1], Icy Cape [IC1], and Point Barrow [BF2]) will be recovered in 2017, analyzed, and results reported in a supplemental report to be submitted to NMFS and USFWS during winter 2017/2018.

Figure 3-1. Locations of PAM Moorings Analyzed for Marine Mammal Vocalizations and Cable-Lay Underwater Sound Levels



Marine Mammal Detections

The presence of marine mammals was analyzed using the software SoundChecker, which facilitates quick searches of large databases for signature vocalizations. All of the long-term acoustic data (100% of the image files) were analyzed manually for presence of the following: fin whales in the low frequency band; bowhead, right, humpback, gray, and minke whales, walrus, unidentified pinnipeds as well as vessel noise and seismic airguns in the mid-frequency band; and beluga, killer whale, minke whale (boing call), bearded and ribbon seals, and environmental noise (ice) in the high frequency band. Vocalizations by ringed and spotted seals are too limited for use in detection studies. The objective was to document the general marine soundscape and specifically marine mammal vocalizations before (2 weeks), during (1 week), and after (2 weeks) passage of the cable-lay operations.

For the most part, the composition of species detected at each mooring matched what was expected, given the locations and time of year. However, there was a detection (one day) of fin whales offshore of Wainwright (WT1), although they have been detected there before.

Fin whales were the most common species detected from the Bering Sea mooring (NM1) offshore of Nome (Quintillion PSOs also observed them there), with these whales present during 17 of the 35 days analyzed. Gray and killer whales were detected during 13 days each, while humpback whales were detected on seven days and walrus on four days. All of these species may have been transiting through the area.

Humpback whales were the mostly commonly detected species at the Kotzebue Sound offshore mooring (KZ1), with presence confirmed over 28 of the 42 days of collected data. Gray whales were detected on 11 days, killer whales three days, fin whales two days, and bearded seals one day.

Matching the marine mammal observations recorded during the PSO monitoring program, walrus where the most prevalent marine mammal detected offshore of Wainwright (WT1), with presence detected during 75% (24 days) of the 32 days of data collection. Presence of walrus correlated with ice presence. Bowhead whales were detected during 12 of the 32 days, and a few detections were made of bearded seals, gray whales, beluga whales, fin whales, and unidentified pinnipeds. PSOs also recorded bowhead whales offshore Wainwright, but they also found gray whales to be considerably more common than the acoustical monitoring suggested.

3.2.2.1. Cable-Lay Noise Characterization

The objective of the noise characterization was to document underwater noise contribution associated with cable-lay operations passing the vicinity of the moorings. Vessel operations significantly increased ambient noise levels. At KZ1 ambient levels were 9 to 15 dB higher (depending on frequency range) when active vessels were present (closest approach about 6 km [3.7 mi]), while levels increased a lesser 4 to 10 dB at WT1, which was located farther (about 16 km [9.9 mi]) from the route.

In all cases, cable ships were louder as they approached moorings than when they moved away from them. First detection of the vessels ranged from 32.3 km [20.1 mi] (Ile de Sein approaching WT1) to 50.1 km [31.1 mi] (Ile de Brehat approaching NM1), while noise from vessels leaving faded to background at ranges from 18 km (11.2 mi) (WT1) to 28.8 km (17.9 mi) (NM1). There is no clear explanation for this, other than bow thruster operation may project a louder noise signature forward of the vessel.



Noise emanating from the cable ships appeared to be similar to those measured by I&R (2016) during the SSV study. The loudest measured SPL (121.9 dB re 1 μPa [rms]) emanating from the Ile de Brehat at KZ1 occurred when the vessel was 6.2 km (3.9 mi) away, and the loudest measured noise from the Ile de Sein was 109.9 dB re 1 μPa (rms) when the ship was 16.3 km (10.1 mi) (from the mooring (the ship never approached the mooring close enough to exceed 120 dB). These values suggest a radial distance of between about 5 and 8 km (3.1 and 5.0 mi) to the 120-dB isopleth (Level B harassment threshold). However, the Ile de Brehat was measured producing an SPL of 125.5 dB re 1 μPa (rms) when still 8.4 km (5.2 mi) from mooring NM1, indicating a louder source on that day (August 6). But further examination of the data (Appendix D, Figure 9C) shows that the 125.5 dB value represents an anomalous, less than one second, spike with noise levels during the minutes before and after consistently at 118 dB re 1 μPa (rms). The 118-dB value roughly extrapolates to a 7 km (4.3 mi) distance to the 120-dB threshold.

The cause of the spike appears to be unrelated to vessel noise, but rather a plow slip recorded at that time, which probably created a loud bang when the plow reengaged (dug into) the seafloor as the vessel was pulling at high power. The anomaly does not represent the normal acoustics associated with the cable-lay vessels.

3.2.2.2. Project Effects

The final objective was to assess any changes in the general marine soundscape and marine mammal vocalizations associated with the presence of cable-lay operations. However, the report (Appendix D) states:

“(t)here are very little data available to support any assessment of the impact of noise on the acoustic behavior of the marine mammals present.”

The strongest correlation showed a decrease in walrus calling during periods of saturated vessel noise at mooring WT1, but this was explained as more likely a result of lower ice concentrations than noise impacts. The cable-lay operation could not work in the vicinity of WT1 until after the ice receded. It is likely the pagophilic walruses receded with the ice. Fin whales were also detected from mooring NM1 before and after cable-lay operations, but not during. However, it is not clear whether this was due to Quintillion’s operations displacing the whales, the vessel noise masking the ability to detect the whales, or natural movements. Noise from vessels not associated with Quintillion’s project was also detected during periods of fin whale vocalization, suggesting that vessel noise did not cause the whales to cease vocalizing.

Kotzebue

Two moorings (KS1 and KS2) were placed in Kotzebue Sound near the village of Kotzebue approximately 1 and 2 km (0.6 and 1.2 mi), respectively, from the route with the intention of collecting both barge and ship sound levels near planned nearshore operations. These shallow-water moorings were deployed for 13 days and retrieved on October 4 before advancing freeze-up prevented small vessel retrieval. Unfortunately, nearshore cable-lay activities by the Ile de Sein and Swissco 48 did not begin until after October 4; therefore, no acoustical data was collected for these operations. Further, breaking waves and heavy rain triggered a large number of false detections preventing effective application of the automated SoundChecker software. A manual scan of the files is planned, but completion of manual analysis of the 1,585 5-minute (min) files



was not possible in time to be included in this 90-day report. The marine mammal detection and soundscape results will be included in next year’s supplemental report.



4. MARINE MAMMAL MONITORING IMPLEMENTATION

This sections summarizes the efforts to implement the Marine Mammal Monitoring and Mitigation Plan (4MP) and stipulations summarized in the NMFS and USFWS IHAs (Appendix A).

4.1. Harassment Zones Prior to the SSV, the primary underwater noise concern was Level B harassment noise emanating from thrusters used by cable ships (Ile de Brehat and Ile de Sein) during continuous DP and the cavitation noise from small anchor-handling tugs during anchor maneuvering activities associated with the cable-lay barges (CB Networker and Swissco 48). The SSV determined that noise emitted from the cavitation of the drive propellers of the cable ships when pulling the plow through the hard seafloor dominated the sound signature. The results of the SSV are discussed in detail in Section 3, but the main objective was to determine the radial distances to Level B harassment thresholds, which were used to establish the harassment zones that were monitored by the PSOs. Where measurements were not possible, proxy values from the literature were used. The established monitoring zones are listed in Table 4-1.

Table 4-1. Harassment Zones Monitored by the PSOs during the 2016 Operations

Vessel Type Activity Distance to 120 dB isopleth

Cable Ship Plow Cable Lay 5.35 km

Cable Ship Surface Lay with Dynamic Positioning 2.30 km

Cable Barge Cable Lay 1.23 km

Anchor-Handling Tugs Anchor Pulling 5.13 km

The cable ship and cable barge radial distances are from the results of the SSV conducted by I&R (Section 3 and Appendix C). For safety reasons, noise sources could not be turned on and off to isolate and measure each individual source at the time the measurements of the ship and barge were being taken. Thus, the distance represents maximum noise levels from the combined sources. The anchor-handling tug was not active at the time of the SSV; therefore, the sound was not measured. The 5.13 km (3.20 mi) distance to threshold shown in Table 4-1 is from measurements by Hannay et al. (2004) of the Katun, a 2,721-ton anchor-handling tug during an anchor pull. The 5.13 km was determined by applying I&R’s spreading model of 17.4 Log R from their measurements at Nome to Hannay et al.’s source value of 184.4 dB re 1 μPa (rms) (which was less than the source value of 185 dB re 1 μPa [rms] I&R measured for the Ile de Brehat). The radial distance is probably conservative given the larger Katun has a bollard pull of 157 tons compared to 70 tons for the Vos Thalia. This represented the monitoring zone during periods of active anchor handling, although the PSOs actually monitored to the maximum practical distance, which varies depending on visibility conditions.



The continuous noise from the cable-lay operations did not significantly exceed (<4 m in all cases) permanent threshold shift (PTS) criteria, thus established safety shutdown zones were not needed to prevent Level A harassment.

4.2. Methods

Monitoring Methods Qualified PSOs were stationed onboard each of the cable ships and cable barges to actively monitor for marine mammals and implement mitigation when necessary. Mitigation measures are described in the IHAs (Appendix A). PSOs were not required onboard vessels lacking berthing space (consistent with U.S. Coast Guard regulations); therefore, they were not stationed on any of the support vessels during this program. However, the smaller vessels were nearly always in proximity of a vessel supporting PSOs.

PSOs actively monitored during cable-lay operations activities that occurred during daylight hours and during most other daylight activities (e.g., transit). PSOs did not monitor during periods of inclement weather or darkness when visibility was ineffective or if it was unsafe. Three PSOs were deployed on each of the cable ships and two were stationed onboard each barge (where berthing space limited the number of PSOs). One PSO was withdrawn from the Ile de Brehat on October 10 when reduced daylight hours eliminated the need for three observers. All other PSOs remained on board for the entire program (dates summarized in Table 4-2). There was an experienced Lead PSO and one local Alaskan Native observer on each vessel. Lead PSOs were responsible for in-field oversight of the PSO team, data management and quality control, serving as the primary point of contact on each vessel, and daily submittal of data and reports.

Table 4-2. Dates (2016) PSOs Boarded and Disembarked each Vessel

Vessel Boarding Disembarkment Total Days Onboard Total Distance Traveled (km)

Ile de Brehat Jul 17 Nov 11 118 8,100

Ile de Sein Aug 05 Oct 27 84 15,905

CB Networker Jul 03 Oct 20 110 5,134

Swissco 48 Aug 09 Oct 21 74 5,081

At least one PSO was on watch at all times during daylight operations, including transit and vessel-standby (e.g., bad weather) periods. When vessels were on extended standby with no active project operations, PSOs conducted opportunistic off-watch observations, or spot-watches, where they would do a single scan each hour and document observations. This opportunistic data were collected to provide continuity throughout the dataset. Watches were conducted from the bridge of all vessels, as well as the flying bridges on the barges when weather allowed, to improve observation vantage. Eye height above sea level (ASL) was measured by the PSOs once onboard and periodically checked throughout the program to ensure continued accuracy. The approximate eye heights ASL from the bridge of the cable ships were 25 m (82 ft) for the Ile de Brehat and 22 m (72 ft) for the Ile de Sein. The cable barges provided lower vantage points from the bridge (CB Networker: 7 m [23 ft]; Swissco 48: 11 m [36 ft]), so PSOs observed from the flying bridge(s)



when safe to do so. The CB Networker had two flying bridge decks with heights to eye level of 10 m (33 ft) and 13 m (43 ft) ASL, respectively. The single flying bridge on the Swissco 48 had an approximate eye height of 14 m (46 ft) ASL.

During daylight, at least one PSO systematically scanned the area around the vessel alternating between the naked eye and use of Fujinon (7x50) reticle binoculars. Because the vessels were moving slowly (approximately 0.5 knots [kt]) during cable-lay operations activities, PSOs regularly scanned behind the vessel for marine mammals. Distance to marine mammals were estimated using reticle binoculars, clinometers, or the best estimate determined by naked eye. Range finders were also provided to aid in distance estimation. Night vision devices were available on the cable ships.

Environmental data were collected approximately every 30 min that PSOs were on watch or whenever conditions or vessel activities substantially changed. This data included, but was not limited to: date, time, vessel position and speed, sea state, visibility, precipitation, and ice cover. Marine mammal data were recorded for all sightings at the time of observation, and included, but was not limited to: date, time, vessel location at time of sighting, species, group size, number of juveniles in group, distance from vessel, reactionary behavior, and mitigation type and implementation time (if necessary). All environmental and marine mammal data were collected on computers for entries on an electronic database, which was exported and emailed daily to Anchorage headquarters for additional quality control and reporting.

Analysis Methods

Analysis of data collected by PSOs involved: 1) categorization by PSO effort, species groups, noise activities, and environmental conditions; 2) initial and reactionary behavior of marine mammals; and 3) estimating the number of marine mammals by species that were potentially affected by the project noise.

4.2.2.1. Data Categorization

• PSO effort is defined as the number of hours at least one observer was on watch collecting environmental and marine mammal sighting data during daylight. PSO effort was summarized by watch status, area, vessel noise activity, and sea state. “Usable PSO effort” (explained below) summaries were calculated for additional environmental conditions and speed class.

• Marine mammal sighting data were summarized by species groups, noise activity, and environmental conditions. Species groups include cetaceans, pinnipeds (excluding Pacific walrus), Pacific walrus, and polar bear. Pacific walrus and polar bears were analyzed separately from cetaceans and pinnipeds due to their separate management by USFWS.

• PSO sighting rates (number of sightings per 10 hours [h] of usable PSO effort) were based on initial sighting distance and calculated using sighting and environmental data which met the criteria for “Usable PSO Effort”: at least one PSO on watch, within the project area, periods of good sighting conditions (daylight and sea state ≤5 [See Appendix E for Beaufort sea state scale definitions]). Due to limited sighting data, sighting rates were calculated for species that were observed greater than 10 times across all vessels. Cable-lay vessels all moved so slowly during cable lay that use of more expansive criteria was irrelevant.



• All marine mammal sighting summaries excluded resightings to avoid unnecessary count inflation. A “Best Count” for each observation was assigned for summaries.

• General behavior and reactionary behaviors were summarized by species, noise activity, and distance (Closest Point of Approach or CPA) to noise activity. Behavior and reaction definitions are in Appendix F.

• Geographic boundaries were implemented around the project area to isolate project-related activities from transit to/from Dutch Harbor (Figure 2-1). All activities north of 64°N were considered within the project area.

• Periods when visibility varied around the vessel (e.g., 10 km [6.2 mi] forward and 4 km [2.5 mi] aft) due to fog or twilight was recorded as >3.5 km (2.2 mi) (when visibility was variable but greater than 3.5 km in all directions) or <3.5 km (2.2 mi) (when visibility was variable but less than 3.5 km in all directions). Unlimited visibility was captured as ≥10 km (6.2 mi).

• Noise activity is separated into five categories (listed below) based on the radial distance (km) to the 120-dB sound level threshold (See Section 3 for details on sound levels). Normal vessel noise during transit is not regulated per the NMFS and USFWS; therefore, is not considered in the sound threshold analyses.

o Idle-Anchor (0 km distance to 120-dB threshold): The vessel is either at anchor either idling or with engines off.

o Cable-Laying, Barge (1.23 km [0.76 mi]): CB Networker and Swissco 48 cable-lay operations including trenching with injector (CB Networker), jet burial and sled use (Swissco 48), diver jet burial and/or air-lift tool use (CB Networker and Swissco 48), and anchor handling directly from barge (not associated tugs).

o Cable Surface Lay/Dynamic Positioning (2.35 km [1.46 mi]):

Ile de Brehat and Ile de Sein laying cable directly on seafloor without use of the plow.

All vessel use of thrusters for DP. Thruster use varied, but was considered at maximum capacity for analyses to remain conservative.

o Tug Anchor Handling (5.13 km [3.19 mi]): CB Networker and Swissco 48 barges utilized associated tugs, Vos Thalia and Dana Cruz, respectively, to place and remove anchors.

o Cable Laying, Plow In (5.35 km [3.32 mi]): Ile de Brehat and Ile de Sein cable laying using the plow to bury the cable in the seafloor.

• The Level B harassment threshold for Pacific walrus is 160 dB re 1 μPa (rms). (Only one walrus was observed within this zone during project activities.)

• No noise criteria were designated for polar bear.

• Distance to noise activity was based on the animal’s CPA.



• The numbers of marine mammals that were recorded within an active ensonification zone at least one time per 24-hour period (exposed to harassing level sounds) were considered “potentially exposed”.

4.2.2.2. Estimating Numbers Potentially Affected

It was assumed that any animal that was observed within a noise threshold radii for Level A (injurious) or Level B (harassment) take as “potentially exposed”. The Level A radius was <4 m (2.5 mi) for all species hearing groups and is not examined further. Table 4-3 outlines the 120- and 160-dB harassment thresholds (ensonification radii) used to determine potential exposures, measured during the SSV (Section 3). The 120-dB zone for continuous sound was monitored for all marine mammal species and the 160-dB zone was monitored only for walrus.

Table 4-3. Ensonification Zones for Vessel Activities

Vessel Activity Ensonification Zone Radii (m)

(Level B Take) 120 dB 160 dB

Cable Laying, Plow In 5350 29 Tug Anchor Handling 5130 26 Cable Surface Lay/DP 2300 15 Cable Laying, Barge 1225 9



5. MARINE MAMMAL MONITORING RESULTS

5.1. Protected Species Observer Effort PSOs boarded the two cable ships (Ile de Brehat and Ile de Sein) and two cable barges (CB Networker and Swissco 48) at staggered times in July and August 2016. Days onboard each vessel varied from 74 to 118 days, and the distance each vessel traveled while the PSOs were onboard also varied from over 5,000 km (3,107 mi) to nearly 16,000 km (9,942 mi) (Table 4-2). PSOs boarded and disembarked the ships in Dutch Harbor and additionally monitored for marine mammals during transit to and from the project area (Figure 2-1). The barges were boarded and disembarked in Nome.

During the 386 days of combined PSO effort, a total of 5,433 h of effort was dedicated to actively monitoring for marine mammals in daylight, including the cable ship transit from Dutch Harbor to the Project Area (Figure 5-1).

Figure 5-1. On-Watch PSO Effort within the Transit and Project Areas by Month

PSO Effort by Watch Status

The results described in the sections and subsections below do not include results obtained in the transit area unless specifically noted. Hereafter, speed is presented in knots and all other numeric values presented in metric units.

PSO effort was classified as either “on-watch” or “off-watch”, whereby on-watch was when one or more PSOs were actively observing for marine mammals and collecting environmental/sighting data during daylight periods. Off-watch status indicates periods when no PSOs were actively observing for marine mammals, but performed spot-watches when either notified of a marine mammal during darkness when PSOs were not required to be on-watch or during extended periods of standby (when no project activities were occurring or during bad weather where observation conditions were not safe). Duration of darkness

294.6593.0

383.1 325.389.5

370.0

606.6

420.3212.3

523.3

456.2

252.9

393.5

292.1

220.2

0

500

1000

1500

2000

2500

Jul Aug Sep Oct Nov

PSO

Effo

rt (h

)

Month

Ile de BrehatCB NetworkerIle de SeinSwissco 48



increased as the season progressed, thus increasing the off-watch periods. Figure 5-2 shows the total level of hours by watch status within the transit and project area (See Section 5.1.2).

Figure 5-2. PSO Effort in both the Transit and Project Area by Watch Status

On-Watch PSO Effort by Area

PSOs onboard the cable ships conducted on-watch marine mammal observations during transit between Dutch Harbor and the project area. The Ile de Brehat conducted 92.3 h of on-watch observations along the transit route and the Ile de Sein PSOs observed for 57.9 h. Figure 2-1 shows the project area and the approximate route traveled during transit. Within the project area itself, the PSOs on all vessels conducted a total of 5,282.7 h of on-watch effort.

The following summaries are of daylight on-watch PSO effort within the project area (north of 64°N) only.

On-Watch PSO Effort in the Project Area by Vessel Noise Activity

The cable ships operated differently than the cable barges relative to the cable-lay methods. Section 4.2.2.1 defines the vessel activities in relation to the different cable vessels, while Table 5-1 highlights the on-watch PSO effort for each vessel by relevant vessel activity. The distance (km) to the 120-dB Level B threshold is identified for each activity.

1685.51609.3

1232.4

905.9889.6 907.3

459.9 416.0

0

200

400

600

800

1000

1200

1400

1600

1800

Ile de Brehat CB Networker Ile de Sein Swissco 48

PSO

Effo

rt (h

)

Vessel

On-Watch

Off-Watch



Table 5-1. On-Watch PSO Effort by Vessel Activity within the Project Area

Vessel Vessel Activity

(Distance to 120-dB Threshold) Ile de Brehat Ile de Sein CB Networker Swissco 48 Total

On-Watch PSO Effort (h) Cable Laying, Plow In

(5.35 km) 778.2 355.6 - - 1133.8

Cable Laying, Plow Out1 (2.30 km) 162.9 108.3 - - 271.2

Anchor Handling, Barge2 (1.23 km) - - 21.8 35.0 56.9

Anchor Handling, Tugs (5.13 km) - - 8.3 33.8 42.1

Cable Laying, Injector On2 (1.23 km) - - 145.6 - 145.6

Cable Laying with Sled/Airlift2 (1.23 km) - - - 100.7 100.7

Cable Laying with Sled/Airlift, DP2 (1.23 km) - - - 130.6 130.6

Idle-DP1 (2.30 km) 476.1 480.5 581.0 9.5 1547.1

Idle-Anchor (0 km) 13.8 - 508.7 391.4 913.8

Transit (N/A) 162.2 230.1 343.8 204.8 940.9

Total 1593.2 1174.5 1609.2 905.8 5282.7 1 Referred to as Cable Surface Lay/DP throughout the report because the 120-dB ensonification zone is the same (2.30 km). 2 Referred to as Cable Laying, Barge throughout the report because the 120-dB ensonification zone is the same (1.23 km). DP = Dynamic Positioning

On-Watch PSO Effort in the Project Area by Sea State

The most common sea states observed during on-watch PSO effort in the project area were sea states 2 through 4 (59.4% or 3,139.7 h). Of total on-watch PSO effort (5,282.7 h), 83.1% or 4,391.5 h occurred during sea states 5 or less, comprising effort that met the “usable PSO effort” criteria (See Section 4.2.2.1) (Figure 5-3).



Figure 5-3. Usable PSO Effort in the Project Area by Sea State

Usable PSO Effort

Approximately 83% (4,391.5 h) of total on-watch PSO effort (5,282.7 h) met the criteria to be considered usable PSO effort and was used for calculating sighting rates described in Section 4.2.2.1. Table 5-2 lists the total on-watch PSO effort compared to usable PSO effort.

Table 5-2. Total On-Watch PSO Effort and Usable PSO Effort

Vessel Total On-Watch PSO Effort (h) Usable PSO Effort (h)

Ile de Brehat 1593.2 1148.1

CB Networker 1609.3 1399.7

Ile de Sein 1174.4 1056.5

Swissco 48 905.9 787.1

Total 5282.7 4391.5

The following sections (5.1.5.1 to 5.1.5.4) provide summaries including only usable data, again defined as sea state 5 or less, to be consistent with sighting rate analyses in Section 5.2.

5.1.5.1. Usable PSO Effort in the Project Area by Precipitation

No precipitation was recorded during 66.0% of on-watch usable PSO effort in the project area (Figure 5-4). Fog (intermittent) was the most common form of precipitation (25.8% of all usable effort). Other precipitation types (mist, rain, snow) occurred at low frequencies.

0.2

57.7

266.

4 296.

7

275.

3

251.

8

168.

7 202.

3

41.4

31.5

1.117

.7

157.

3

273.

0

452.

0

320.

5

179.

2

164.

4

23.0

18.6

3.6

31.4

174.

5

273.

9

270.

7

168.

9

137.

1

81.6

33.7

2.77.8

74.1

139.

8 166.

1

236.

3

163.

1

90.9

26.9

1.0

0

50

100

150

200

250

300

350

400

450

500

0 1 2 3 4 5 6 7 8 9 10

PSO

Effo

rt (h

)

Beaufort Sea State

Ile de Brehat

CB Networker

Ile de Sein

Swissco 48



Figure 5-4. Usable PSO Effort in the Project Area by Precipitation Type

5.1.5.2. Usable PSO Effort in the Project Area by Visibility

Visibility was unlimited (≥10 km) for approximately 53% of on-watch usable PSO effort in the project area (Figure 5-5). Variable visibility (<3.5 or >3.5 km, described in Section 4.2.2.1), primarily due to fog or twilight, was recorded during approximately 10% of on-watch usable effort PSO effort, indicating that viewing conditions were not consistent in all directions around the vessels during those periods.

Figure 5-5. Usable PSO Effort in the Project Area by Visibility

740.

2

330.

1

20.4

13.7 43

.7

940.

5

282.

5

59.0 98

.6

19.1

635.

8

364.

2

0.8 21

.1

34.6

583.

9

157.

4

7.8 29

.3

8.8

0

100

200

300

400

500

600

700

800

900

1000

None Fog Mist Rain Snow

Usa

ble

PSO

Effo

rt (h

)

Precipitation

Ile de Brehat

CB Networker

Ile de Sein

Swissco 48

184.

6

36.5

25.8

30.3

257.

1

18.7

20.7

10.4

15.9

26.7

27.5

494.

0

75.5

41.0

40.4

43.1

5.9 46

.7

33.7

31.1

36.8 74

.3 115.

1

856.

1

201.

5

51.4

43.8

4.5 37

.3

37.6 65

.6

39.4

146.

1

6.6

422.

6

18.1

11.8

7.8

67.5

35.7

7.2 16

.7

6.6 10.6

15.4

15.9

573.

7

0

100

200

300

400

500

600

700

800

900

1 2 3 <3.5 >3.5 4 5 6 7 8 9 ≥10

Usa

ble

PSO

Effo

rt (h

)

Visibility (km)

Ile de Brehat

CB Networker

Ile de Sein

Swissco 48



5.1.5.3. Usable PSO Effort in the Project Area by Ice Coverage

Ice coverage was measured as a percentage relative to available viewing area. If the view was partially obscured by fog to a 5-km viewing radius, the ice was measured within that area and not estimated beyond. If ice was noticed when the fog lifted, new data were collected to capture the change in viewing conditions. No ice was documented for 89% of on-watch usable PSO effort within the project area, 6% of effort was with less than 10% ice cover within the viewing area, and the remaining 5% of effort distributed between 10% and 80% ice coverage. (Figure 5-6).

Figure 5-6. Usable PSO Effort in the Project Area by Percent Ice Coverage

5.1.5.4. Usable PSO Effort in the Project Area by Speed Class

Cable laying requires that vessels travel at slow speeds, resulting in over 90% of on-watch usable PSO effort when vessel speeds were <5 kt (Figure 5-7). All vessels traveled at speeds between 5 and 10 kt at some point during the project (6.1%). The cable ships, Ile de Sein and Ile de Brehat, were able to transit at faster speeds than the barges (which were actually under tow when transiting), which resulted in some speeds >10 kt within the project area (3.3%). In addition, and not included in usable PSO effort, the cable ships traveled at increased speeds during transit to and from Dutch Harbor (but south of 64°N), resulting in speeds greater than 10 kt for approximately 53% of total on-watch PSO effort during these transits outside the project area.

1134

.8

12.4

0.1

0.8

1336

.0

50.5

7.9

2.6

0.5

0.3

0.1

1.7

728.

0

152.

9

81.0

20.0

26.4

24.9

16.3

2.5

2.5

2.0

694.

1

52.8

6.2

2.4

1.4

5.3 13.1

6.6

1.9

3.4

0

200

400

600

800

1000

1200

1400

1600

None <10 10 20 30 40 50 60 70 80

Usa

ble

PSO

Effo

rt (h

)

Ice Coverage (%)

Ile de Brehat

CB Networker

Ile de Sein

Swissco 48



Figure 5-7. Usable PSO Effort within the Project Area by Speed Class

5.2. Marine Mammals Recorded In total, 858 observations of 3,151 individual marine mammals were recorded from all cable-lay vessels during all activities, including transit from Dutch Harbor (cable ships only) and during off-watch PSO effort (details in Appendix G). These summaries exclude carcasses which are addressed in Section 5.2.5. One sea otter was observed from the Ile de Sein during transit as the vessel was departing Dutch Harbor on August 6, but is not further discussed in these summaries.

Approximately 5.7% of total marine mammal sightings (49 groups) occurred from the Ile de Brehat and Ile de Sein during transit to/from the project area while the remaining 94.4% of sightings (810 groups) occurred within the project area (north of 64°N; Figure 5-8 and Appendix H) from all vessels. Of the 810 sightings within the project area, 16.0% were observed from the Ile de Brehat, 14.3% from the Ile de Sein, 34.4% from the CB Networker, and 35.2% from the Swissco 48. The Swissco 48, although operating at sea for the fewest number of days, observed the greatest number of sightings due to the duration of time (approximately 30 days) spent close to known spotted seal haulouts near Kotzebue (Whiting et al. 2011) (Section 5.2.2).

Of the 810 groups within the project area, 694 were observed during usable sighting conditions. Sighting rate calculations were limited to species that were confidently identified and observed more than 10 times (562 sightings) because sighting rates of smaller samples are less meaningful. The species analyzed include bowhead whale, gray whale, harbor porpoise, bearded seal, ringed seal, spotted seal, and Pacific walrus.

1052

.1

43.7

52.3

1347

.0

52.7

916.

4

49.3 90.7

666.

2

120.

9

0

200

400

600

800

1000

1200

1400

1600

<5 5-10 >10

Usa

ble

PSO

Effo

rt (h

)

Speed Class (kt)

Ile de Brehat

CB Networker

Ile de Sein

Swissco 48



Figure 5-8. Total Sightings for all Cable Vessels within the Project Area

Cetaceans

A total of 238 groups of 566 individual cetaceans (whales and porpoises) were observed from all cable vessels within the project area (Table 5-3 and Appendix H). Gray whales were the most commonly observed cetacean with 82 groups of 225 individuals recorded. Group size ranged from 1 to 15, with the exception of one large group of 50 individuals observed from the Ile de Brehat over an extended period of 10.2 hours on September 8. During that observation, the distance to the animals ranged from approximately 1.2 to 7.0 km, and the vessel was stationary using DP while conducting ROV operations. This large group was likely a herd made up of several smaller groups of animals; however, it was recorded as a single group to avoid inflating group and animal counts by recounting the same individuals. This record, however, biases the mean group size. Without this sighting, the mean group size was 2.16 (s.d. = 2.43).

Bowhead whales were observed from all cable vessels except the Swissco 48, which primarily operated in the nearshore waters of the Chukchi Sea. Bowhead whale group size ranged from 1 to 10 with a mean of 1.7. Approximately two-thirds (44) of the bowhead whale sightings occurred from the CB Networker while it lay idle off Oliktok Point during the fall migration.

810

279130 116

285

3041

858

372

820991

0

500

1000

1500

2000

2500

3000

3500

All Vessels CB Networker Ile de Brehat Ile de Sein Swissco 48

Num

ber o

f Mar

ine

Mam

mal

s

Vessel

Groups

Individuals



Table 5-3. Cetacean Groups (Individuals) Observed from all Cable Vessels within the Project Area

On August 17, PSOs onboard the Ile de Brehat observed an extended group of 36 humpback whales (including 4 juveniles), over the course of four hours, within the project area in the Bering Strait northeast of Wales (Figure 5-9). The whales were actively breaching, lob-tailing, and flipper slapping. The animals ranged in distance from the vessel between 50 and 1,500 m, but did not demonstrate any notable reactions to the vessels presence. One whale was documented swimming under the vessel and observed on the other side to continue swimming away.

Twenty juvenile cetaceans were recorded within the project area including 11 gray whales, four humpbacks from the large group of 36, two bowhead whales, one fin whale, one killer whale, and one unidentified mysticete. Juvenile cetaceans were always observed with one or more larger whales often displaying mother-calf positioning where the calf follows close alongside or slightly behind the mother.

Approximately 23.9% of cetacean groups observed (20.5% of individuals) were unidentified due to sighting distance (mean distance at closest approach: 2,693.1 m), sighting brevity, or limited visibility due to environmental conditions such as precipitation or high sea state. None of the unidentified cetaceans displayed reactions.

Species Ile de Brehat Ile de Sein CB

Networker Swissco 48 Total Bowhead Whale 9 (13) 12 (26) 44 (73) - 65 (112) Fin Whale 2 (3) - - 1 (2) 3 (5) Gray Whale 31 (130) 30 (64) 7 (11) 14 (20) 82 (225) Harbor Porpoise 2 (6) 2 (9) 12 (24) 4 (6) 20 (45) Humpback Whale 2 (39) - - - 2 (39) Killer Whale 3 (7) - - 2 (12) 5 (19) Minke Whale 2 (2) - 1 (1) 1 (2) 4 (5) Unidentified Mysticete 11 (34) - 1 (1) 15 (38) 27 (73) Unidentified Porpoise - 1 (1) - 3 (3) 4 (4) Unidentified Whale 12 (21) 4 (6) 5 (6) 5 (6) 26 (39)

Total 73 (219) 49 (106) 70 (116) 45 (89) 238 (566)



Figure 5-9. Photo of Humpback Whales taken August 17, 2016 from the Ile de Brehat

5.2.1.1. Sea State

Cetaceans were recorded during Beaufort sea states ranging from 0 to 7, with the greatest number of sightings (153 groups or 64.3%) observed during sea states 2 through 4 (Table 5-4), which closely coincides with the greatest level of on-watch PSO effort (59.4%). No cetaceans were observed at sea states higher than 7, due to limited PSO effort (1.9%) and poor visibility during these conditions. Although small in size, harbor porpoises were observed in all sea states except zero, including the highest of sea state 7; however, all harbor porpoises observed in sea states greater than 3 were observed at close distances of less than 500 m from the vessel. Generally, only the larger whale species were observed at the higher sea states (>6). Only 1% of on-watch PSO effort occurred during sea state 0, which explains why so few species or individuals were observed during this condition. Calm conditions were very rare during 2016. Approximately 53% of unidentified cetaceans occurred during sea states 3 or greater, indicating that poor visibility due to higher sea state was a factor in limiting species identification.



Table 5-4. Cetacean Groups (Individuals) Observed from all Cable Vessels within the Project Area by Sea State

Species Beaufort Sea State

Total 0 1 2 3 4 5 6 7

Bowhead Whale - 7 (11) 16 (33) 14 (32) 14 (20) 6 (6) 5 (6) 3 (4) 65 (112) Fin Whale - - - 1(1) 1 (2) 1(2) - - 3 (5)

Gray Whale 4 (7) 6 (7) 15 (84) 17 (45) 21 (46) 12

(22) 6 (12) 1 (2) 82 (225)

Harbor Porpoise - 6 (16) 2 (4) 5 (10) 2 (3) 1 (1) 2 (6) 2 (5) 20 (45) Humpback Whale - - - - - - - 2 (39) 2 (39) Killer Whale - - 1 (4) 1 (2) 2 (12) 1 (1) - - 5 (19) Minke Whale - 1 (1) 2 (2) 1 (2) - - - - 4 (5) Unidentified Mysticete - 4 (11) 5 (19) 5 (17) 6 (14) 5 (10) 1 (1) 1 (1) 27 (73)

Unidentified Porpoise - 1 (1) - 2 (2) - 1 (1) - - 4 (4) Unidentified Whale - - 5 (15) 5 (5) 10 (13) 3 (3) 2 (2) 1 (1) 26 (39)

Total 4 (7)

25 (47)

46 (161)

51 (116)

56 (110)

30 (46)

16 (27)

10 (52)

238 (566)

5.2.1.2. Vessel Noise Activities

As compared to all other activities, more cetaceans (32.4% of all groups) were observed during cable surface (on seafloor) lay or DP activities across all vessels (Table 5-5). This is unsurprising given that more on-watch PSO effort (34.6%) occurred during these activities compared to others. Gray whales (37 groups, 149 individuals) and bowhead whales (27 groups, 49 individuals) were the most recorded cetacean species during ship-based cable laying activities (plow in or surface lay) since much of this activity occurred offshore within gray whale feeding habitat (Nelson et al. 1994, Clarke et al. 2015 or bowhead whale migration corridors (Quakenbush et al. 2013). Few cetaceans were observed from barges when laying cable in shallow nearshore waters.



Table 5-5. Cetacean Groups (Individuals) Observed from All Cable Vessels within the Project Area by Vessel Noise Activity

Species Cable Laying, Plow In

Cable Surface Lay/DP

Cable Laying, Barge

Tug Anchor Handling

Idle, Anchor

Transit Total

Bowhead Whale 1 (2) 27 (47) 4 (14) - 6 (7) 27

(42) 65

(112) Fin Whale 1 (2) 1 (1) - - - 1 (2) 3 (5)

Gray Whale 17 (40) 30 (109) 3 (4) - 13 (19) 19 (53)

82 (225)

Harbor Porpoise - 5 (12) 1 (1) - 2 (4) 12

(28) 20

(45) Humpback Whale - 2 (39) - - - - 2 (39)

Killer Whale 1 (1) - - - 2 (12) 2 (6) 5 (19) Minke Whale - 1 (1) - - - 3 (4) 4 (5) Unidentified Mysticete 3 (16) 5 (9) 3 (10) 1 (2) 10 (25) 5

(11) 27

(73) Unidentified Porpoise - - - - 2 (2) 2 (2) 4 (4)

Unidentified Whale 7 (16) 6 (8) - - 3 (3) 10

(12) 26

(39)

Total 30 (77) 77 (226) 11 (29) 1 (2) 38 (72) 81 (160)

238 (566)

5.2.1.3. Closest Points of Approach

Cetaceans were observed between 10 m and 8,000 m from the vessels (Table 5-6), with a mean CPA of 1,720.1 m (s.d. = 1,728.8 m). Approximately 74% of cetacean sightings occurred within 2 km of the vessels, likely because detectability decreased after that distance, especially during the higher sea states encountered. Only the larger cetaceans – bowhead, gray, and unidentified large whales – were observed at distances greater than 2 km. The large group of 36 humpback whales observed on August 17 were at relatively close distances from the Ile de Brehat ranging from 50 m to 1.5 km, largely because the high sea state (7) at the time limited the sighting range. Gray whales had the greatest CPA range (10 m to 7,039 m) with a relative close mean of 1,115.9 m (s.d. = 1,219.4 m), again probably due to the generally high sea states encountered while operating offshore.



Table 5-6. Cetacean Groups (Individuals) Observed from All Cable Vessels within the Project Area by Closest Distance to Vessel

Species Distance (m)

Total <100 100-

500 501-1000

1001-2000

2001-3000

3001-4000

4001-5000

5001-5500 >5500

Bowhead Whale - 2 (4) 11 (17) 27 (53) 13

(18) 8 (15) 3 (3) - 1 (2) 65 (112)

Fin Whale - 1 (2) - 1 (2) 1 (1) - 3 (5) Gray Whale 2 (2) 21 (27) 27 (53) 25 (124) 2 (6) 2 (8) 1 (1) - 2 (4) 82 (225)

Harbor Porpoise 4 (9) 9 (17) 4 (8) 3 (11) - - - - - 20 (45)

Humpback Whale 1 (36) - 1 (3) - - - - - - 2 (39)

Killer Whale - 4 (14) - - 1 (5) - - - - 5 (19) Minke Whale - 1 (1) 2 (2) 1 (2) - - - - 4 (5)

Unidentified Mysticete 1 (1) 3 (3) 5 (6) 5 (6) 5 (18) 2 (11) 2 (5) 1 (7) 3 (16) 27 (73)

Unidentified Porpoise 2 (2) 2 (2) - - - - - - - 4 (4)

Unidentified Whale 1 (1) 1 (1) 4 (5) 5 (5) 3 (4) 3 (12) 2 (2) 4 (5) 3 (4) 26 (39)

Total 11 (51) 44 (71) 54 (94) 67 (203) 25 (52) 15 (46) 8 (11) 5 (12) 9 (26) 238 (566)

5.2.1.4. Cetacean Behavior

Almost half of the cetacean behaviors (see definitions in Appendix F) observed were a form of traveling (surface active-travel: 20.6%; travel/swim: 27.7%) indicating directional movement, rather than milling behavior (6.7%) (Table 5-7). Gray whales were observed feeding more than other species because, as mentioned earlier, much of the cable-lay activity was within gray whale feeding habitat. Most bowhead whales were recorded as traveling indicative of migration. Blow was recorded as the primary behavior for 16.4% of cetaceans, probably a result of observing large whales (bowhead, fin, and gray whales) at distances too far, or sea states too high, to identify other behaviors.

The behavior “surface active-travel” recorded for the observation of 36 humpback whales from the Ile de Brehat on August 17 included breaching, lob-tailing, and flipper slap behaviors. The high sea state (Beaufort 7) when the sighting occurred indicates that these behaviors were likely not reactionary to the vessel’s presence, but rather normal group behavior in a naturally noisy environment. Additionally, the animals were first observed breaching over 5 km away from the vessel, indicating that this behavior was occurring prior to the vessel’s presence. Further, the whales lingered in the area around the vessel for several hours which suggests they were not affected by the slow-moving (~1 kt) vessel.



Table 5-7. Cetacean Groups (Individuals) Observed from All Cable Vessels within the Project Area by Behavior

Behavior

Species*

Total BHW FW GW HP HBW KW MW UM UP UW

Blow 4 (6) 1 (2) 9 (21) - - - - 14 (32)

11 (12) 39 (73)

Bow Ride - - - 1 (3) - - - - - - 1 (3) Breach - - 4 (5) - 1 (3) - 1 (2) - - - 6 (10) Dive 1 (1) - - - - - 2 (5) - - 3 (6) Feed - 7 (12) - - - - - 1 (2) 8 (14)

Fluke 4 (4) - 10 (27) - - - - 2 (6) - 1 (1) 17 (38)

Look - 1 (1) - - - - - - - 1 (1) Lob-tail 1 (1) - - - - - - - - - 1 (1) Mill 3 (16) - 9 (28) 4 (14) - - - - - - 16 (58) Porpoise - - 1 (1) - - - - 1 (1) - 2 (2)

Surface Active 5 (6) - 10 (29) - - - - 3 (12) 1 (1) 4 (4) 23 (52)

Sink - - - - - 1 (5) - - - - 1 (5) Surface Active-Travel

22 (32) - 15 (81) 6 (12) 1 (36) 2 (11) - 2 (2) - 1 (1) 49 (175)

Travel/Swim 25 (46) 2 (3) 14 (16) 8 (15) - 1 (2) 3 (3) 4 (16) 2 (2) 7 (18) 66 (121)

Unknown - - 3 (5) - - 1 (1) - - - 1 (1) 5 (7)

Total 65

(112) 3 (5) 82

(225) 20

(45) 2 (39) 5 (19) 4 (5) 27

(73) 4 (4) 26

(39) 238

(566) *Species Codes: BHW – bowhead whale, FW – fin whale, GW – gray whale, HP – harbor porpoise, HBW – humpback whale, KW – killer whale, MW – minke whale, UM – unidentified mysticete, UP – unidentified porpoise, UW – unidentified whale.

5.2.1.5. Cetacean Reactionary Behavior and Mitigation Actions

Reactionary behaviors (definitions in Appendix F) were only observed during 3% of all cetacean observations from all vessels within the project area (Table 5-8). PSOs onboard the Ile de Sein observed three bowhead whale groups exhibiting reactionary behaviors (two groups changed direction and one increase speed) while the vessel was in transit in the project area. The whales were observed between 1,500 m and 2,500 m from the vessel and vessel speed was reduced to 5 kt on one occasion to mitigate for reduced visibility (increasing fog). Ile de Sein PSOs also observed a gray whale spy hopping during cable laying activity. The vessel was already traveling slowly (0.1 kt); therefore, no mitigation was called. One gray whale was observed looking at the Swissco 48 while it was milling around the anchored vessel, possibly out of curiosity. The Swissco 48 also observed two gray whales change direction while the vessel was stationary, although whether this change was an actual reaction to the vessel, or a natural movement, is unclear.



Table 5-8. Cetacean Groups (Individuals) Observed from All Cable Vessels within the Project Area by Reactionary Behavior

Species None Look Change Direction Increase Speed Spy Hop Total Bowhead Whale 62 (107) - 2 (4) 1 (1) - 65 (112) Fin Whale 3 (5) - - - - 3 (5) Gray Whale 78 (221) 1 (1) 2 (2) - 1 (1) 82 (225) Harbor Porpoise 20 (45) - - - - 20 (45) Humpback Whale 2 (39) - - - - 2 (39) Killer Whale 5 (19) - - - - 5 (19) Minke Whale 4 (5) - - - - 4 (5) Unidentified Mysticete 27 (73) - - - - 27 (73) Unidentified Porpoise 4 (4) - - - - 4 (4) Unidentified Whale 26 (39) - - - - 26 (39)

Total 231 (557) 1 (1) 4 (6) 1 (1) 1 (1) 238 (566)

5.2.1.6. Cetacean Sighting Rates

Cetaceans with more than 10 observations – bowhead whales, gray whales, and harbor porpoise – were included in the following sighting rate calculations.

5.2.1.6.1. Vessel Activity Noise

Bowhead and gray whale sighting rates were highest of all cetaceans and highest during periods when the cable ships were laying cable on the surface of the seafloor, operating with DP thrusters engaged (Cable Surface Lay/DP), or for all vessels during transit (Figure 5-10). The total cetacean sighting rate during cable laying with the plow in (0.04) was one-third of that during Cable Surface Lay/DP (0.12). However, sea plow operations occurred in shallower waters (<50 m deep) than surface-lay operations, which may account for the difference because bowhead and gray whales in particular prefer the deeper offshore waters.

Figure 5-10. Cetacean Sighting Rates by Vessel Noise Activity

0.00

2

0.05

5

0.00

9

0.00

9

0.05

5

0.03

6

0.05

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0.04

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0.00

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0.02

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0.06

0.07

Cable Laying,Plow In

Cable SurfaceLay/DP

Cable Laying,Barge

Idle-Anchor TransitSigh

tings

/ 10

h U

sabl

e PS

O E

ffort

Vessel Noise Activity

Bowhead Whale

Gray Whale

Harbor Porpoise



5.2.1.6.2. Beaufort Sea State

Consistent with PSO effort, cetacean sighting rates were highest during sea states 2 through 4, and the larger cetaceans (bowhead and gray whales) had the highest sighting rate across almost all sea states (Figure 5-11). Harbor porpoise had the lowest sighting rate in all sea states, which is to be expected given its small size, shy behavior, and possibly low population in the project area.

Figure 5-11. Cetacean Sighting Rates by Sea State

5.2.1.6.3. Precipitation

Not surprisingly, cetacean sighting rates were highest during periods of no precipitation and lower during periods of precipitation (Figure 5-12). The sighting rates are consistent with the level of usable PSO effort during the various precipitation states that observations were conducted. Gray whales, also the most frequently observed cetacean, had a relatively high sighting rate during (intermittent) fog conditions which was more a reflection of the sighting conditions when operating within gray whale feeding areas.

0.00

0

0.01

6

0.03

6

0.03

2

0.03

2

0.01

4

0.00

9 0.01

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0.03

4 0.03

9

0.04

8

0.02

7

0.00

0

0.01

4

0.00

5

0.01

1

0.00

5

0.00

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0.04

0.05

0.06

0 1 2 3 4 5

Sigh

tings

/ 10

h U

sabl

e PS

O E

ffort

Beaufort Sea State

Bowhead Whale

Gray Whale

Harbor Porpoise



Figure 5-12. Cetacean Sighting Rates by Precipitation

5.2.1.6.4. Visibility

Sighting rates for bowhead and gray whales during unlimited conditions (visibility of ≥10 km) were the same (0.08) and over double the other cetacean species (Figure 5-13), reflective of their larger size and distinctive blows compared to harbor porpoise. Gray whales had higher sighting rates at variable and lower visibility than the other species, again, probably reflective of the intermittent fog conditions encountered when operating in gray whale feeding areas.

Figure 5-13. Cetacean Sighting Rates by Visibility

0.07

7

0.03

4

0.00

7

0.00

5

0.00

7

0.08

7

0.07

1

0.00

0 0.01

1

0.00

2

0.03

0

0.00

0

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5

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2

0.00

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None Fog Mist Rain SnowSigh

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O E

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Precipitation

Bowhead Whale

Gray Whale

Harbor Porpoise

0.00

2

0.00

0 0.00

5

0.00

0 0.00

5

0.00

0

0.00

0 0.00

5

0.01

4

0.01

1

0.01

4

0.07

5

0.01

4

0.00

5

0.00

7

0.00

7

0.02

0

0.00

5

0.00

5 0.01

1

0.00

5

0.01

4

0.00

5

0.07

5

0.00

0

0.00

0

0.00

0

0.00

0

0.00

0

0.00

0

0.00

2

0.00

0

0.00

2

0.00

0

0.00

0

0.03

2

0.000

0.010

0.020

0.030

0.040

0.050

0.060

0.070

0.080

1 2 3 <3.5 >3.5 4 5 6 7 8 9 ≥10

Sigh

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Visibility (km)

Bowhead Whale

Gray Whale

Harbor Porpoise



5.2.1.6.5. Ice Coverage

Cetacean sighting rates were highest with no ice present, but as with the other parameters, this is consistent with the amount of usable PSO effort that occurred when no ice was present (Figure 5-14). About 89% of the effort occurred when no ice was present.

Figure 5-14. Cetacean Sighting Rates by Ice Coverage

5.2.1.6.6. Speed Class

Sighting rates were highest during low speeds reflective of the slow speeds required to effectively lay cable in the project area (Figure 5-15). Gray and bowhead whales were observed during speeds >10 kt more from the transiting cable ships, rather than barges that traveled only at slow speeds.

Figure 5-15. Cetacean Sighting Rates by Speed Class

0.11

8

0.00

7

0.00

2

0.00

0

0.00

0

0.00

2

0.00

0

0.00

0

0.00

0

0.13

0

0.02

5

0.00

5

0.00

0

0.00

2 0.00

9

0.00

0

0.00

0

0.00

0

0.03

6

0.00

0

0.00

0

0.00

0

0.00

0

0.00

0

0.00

0

0.00

0

0.00

0

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0.02

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0.12

0.14

None <10 10 20 30 40 50 60 70

Sigh

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Ice Coverage (%)

Bowhead Whale

Gray Whale

Harbor Porpoise

0.093

0.0110.025

0.134

0.009

0.0270.020

0.0140.002

0.00

0.02

0.04

0.06

0.08

0.10

0.12

0.14

0.16

<5 5-10 >10

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Speed Class (kt)

Bowhead Whale

Gray Whale

Harbor Porpoise



Pinnipeds (Excluding Pacific Walrus)

A total of 504 groups of 1,258 individual pinnipeds were observed from all cable vessels within the project area (Table 5-9, Appendix H). Spotted seals were the most recorded pinniped (57% of all pinniped sightings) due to the high number observed from the Swissco 48 during its 30 days of operations near Kotzebue (September 12 through October 11). During this time, PSOs onboard the Swissco 48 observed 108 groups (391 individuals) of seals, many of which were almost certainly resightings of the same seals given the close proximity to known spotted seal haul outs.

Ringed and bearded seals were observed from all vessels in the Chukchi and Beaufort Sea, but were not recorded along either the transit or cable routes within the Bering Sea.

Unidentified pinnipeds made up 11.3% of all pinniped groups (5.2% of individuals) observed. As with cetaceans, this was due to sighting distance (mean distance at closest approach: 322.7 m), sighting brevity, or limited visibility due to environmental conditions such as precipitation or sea state. The majority of the 66 unidentified seals are probably either ringed or spotted seals given the locations of encounter.

A total of 15 juvenile pinnipeds were observed, including five spotted seals, three ringed seals, two bearded seals, and five unidentified seal juveniles. Most juvenile sightings were loners, with age class determined by small body size.

Table 5-9. Pinniped Groups (Individuals) Observed from All Cable Vessels within the Project Area

Species Ile de Brehat Ile de Sein CB Networker Swissco 48 Total Bearded Seal 17 (20) 9 (9) 20 (21) 10 (13) 56 (62) Ringed Seal 7 (7) 5 (6) 86 (94) 3 (3) 101 (110) Spotted Seal 5 (54) 1 (1) 77 (103) 203 (857) 286 (1015) Steller Sea Lion 3 (3) 1 (1) - - 4 (4) Unidentified Seal 21 (21) 12 (16) 5 (7) 19 (22) 57 (66)

Total 53 (105) 28 (33) 188 (225) 235 (895) 504 (1258)

5.2.2.1. Sea State

Pinnipeds were observed during sea states up to 8, with 80.0% of groups (86.6% of individuals) observed during sea states 4 or less (Table 5-10), a condition which represented over 69% of all on-watch PSO effort. Pinnipeds observed in sea states ≥5 were all sighted within 1 km of the vessel.



Table 5-10. Pinniped Groups (Individuals) Observed from All Cable Vessels within the Project Area by Sea State


Total 0 1 2 3 4 5 6 7 8

Bearded Seal 5 (5) 12 (16) 18 (21) 11 (11) 5 (5) 4 (4) 1 (1) - - 56 (63)

Ringed Seal 5 (6) 25 (26) 15 (15) 11 (12) 14 (15) 12 (13)

15 (18)

3 (4)

1 (1) 101 (110)

Spotted Seal 7 (92) 26 (131) 81 (297) 47

(113) 66

(261) 30

(50) 27

(69) 1

(1) 1

(1) 286

(1015)

Steller Sea Lion - - - 2 (2) - 1 (1) - 1 (1) - 4 (4)

Unidentified Seal 4 (6) 12 (14) 17 (20) 13 (15) 7 (7) 4 (4) - - - 57 (66)

Total 21 (109)

75 (187)

131 (353)

84 (153)

92 (288)

51 (72)

43 (88)

5 (6)

2 (2)

504 (1258)


More pinnipeds (38.3% of groups; 42.9% of individuals) were observed while vessels (primarily barges) were at anchor (Table 5-11) than in any other activity. Approximately, 70.4% of spotted seal groups (87.4% of individuals) were observed during Idle-Anchor, which represented only 17.3% of on-watch PSO effort across all vessels. This was influenced by the duration of time (approximately a month) the Swissco 48 was anchored near Kotzebue spotted seal haulouts waiting on weather conditions to improve.

Table 5-11. Pinniped Groups (Individuals) Observed from All Cable Vessels within the Project Area by Vessel Noise Activity

Species

Cable Laying, Plow In


Cable Laying, Barge

Tug Anchor

Handling

Idle, Anchor Transit

Total Bearded Seal 12 (15) 14 (15) 11 (11) - 7 (10) 12 (12) 56 (63) Ringed Seal 1 (1) 29 (32) 16 (16) 1 (1) 37 (42) 17 (18) 101 (110) Spotted Seal 1 (1) 30 (81) 85 (171) 7 (25) 136 (472) 27 (265) 286 (1015) Steller Sea Lion 3 (3) - - - - 1 (1) 4 (4) Unidentified Seal 9 (9) 10 (14) 6 (8) - 13 (16) 19 (19) 57 (66)

Total 26 (29) 83 (142) 118 (206) 8 (26) 193 (540) 76 (315) 504 (1258)


Over 85% of pinniped sightings occurred at 500 m or less (Table 5-12). The closest point of approach for pinnipeds ranged from 1 to 2,500 m with a mean of 222.6 m (s.d. = 255.7 m). The farthest recorded pinnipeds included one ringed seal observed at 1,955 m from the CB Networker and one unidentified seal observed at 2,500 m from the Ile de Sein. Both sightings were during low sea state (Beaufort 1) and good visibility (8 km).



Table 5-12. Pinniped groups (Individuals) Observed from All Cable Vessels within the Project Area by Closest Distance to Vessel

Species Distance (m)

Total <100 100-500 501-1000 1001-2000 2001-3000 Bearded Seal 22 (22) 21 (28) 11 (11) 2 (2) - 56 (63) Ringed Seal 52 (55) 29 (34) 17 (18) 3 (3) - 101 (110) Spotted Seal 78 (304) 176 (599) 31 (107) 1 (5) - 286 (1015)

Steller Sea Lion 2 (2) 2 (2) - - - 4 (4) Unidentified Seal 25 (26) 22 (29) 7 (8) 2 (2) 1 (1) 57 (66)

Total 179 (409) 250 (692) 66 (144) 8 (12) 1 (1) 504 (1258)

5.2.2.4. Pinniped Behavior

Approximately 67% of pinnipeds exhibited common behaviors of looking, milling, diving, and swimming (Table 5-13). One unidentified seal was observed by the splash resulting from thrashing behavior and ultimately changed direction likely in reaction to the presence of the Swissco 48. PSOs onboard the Ile de Brehat recorded two pinnipeds exhibiting “Other” behavior: 1) a single ringed seal initially swimming on its back while milling, then it performed several shallow dives while looking at the vessel when at the surface before it dove from view, and 2) a small, unidentified seal that turned and stared at the vessel before submerging out of view. Feeding behavior was noted when pinnipeds were observed foraging with gulls, diving and exhibiting chewing motions, or with prey in their mouth after a dive. Unknown behaviors were a result of sighting brevity where further details were unattainable.

Table 5-13. Pinniped Groups (Individuals) Observed from All Cable Vessels within the Project Area by Behavior

Behavior Species*

Total BS RS SS SSL US Breach 1 (1) - - - - 1 (1) Dive 6 (6) 7 (7) 14 (20) 1 (1) 9 (9) 37 (43) Feed 1 (1) - 4 (8) - 1 (3) 6 (12) Log 1 (1) - - - - 1 (1) Look 7 (7) 27 (28) 66 (71) - 9 (9) 109 (115) Mill 4 (5) 17 (21) 58 (412) - 5 (7) 84 (445) Other - 1 (1) - - 1 (1) 2 (2) Porpoise 1 (1) 1 (1) - - - 2 (2) Raft 1 (1) - - - - 1 (1) Rest 2 (2) 2 (2) 34 (207) - 1 (1) 39 (212) Surface Active 11 (14) 13 (13) 12 (73) 1 (1) 11 (16) 48 (117) Spyhop - - 2 (2) 1 (1) - 3 (3) Sink - 1 (1) 9 (10) - 3 (3) 13 (14) Surface Active-Travel 15 (15) 19 (20) 8 (17) - 3 (3) 45 (55) Thrash - - - - 1 (1) 1 (1) Travel/Swim 6 (9) 13 (16) 73 (188) 1 (1) 13 (13) 106 (227) Unknown - - 6 (7) - - 6 (7)

Total 56 (63) 101 (110) 286 (1015) 4 (4) 57 (66) 504 (1258) * Species Codes: BS - bearded seal, RS - ringed seal, SS - spotted seal, SSL - Steller sea lion, US - unidentified seal



5.2.2.5. Pinniped Reactionary Behavior and Mitigation

Nearly 62% of pinniped groups and individuals did not react to vessel activities in the project area (Table 5-14). The most commonly observed reaction was “look”, meaning the animal acknowledged the presence of the vessel (29.0% of groups; 20.7% of individuals). The remaining 9.5% of pinniped groups (17.6% of individuals) exhibited behaviors such as splashing as they dove (4.2% of groups, 8.8% of individuals), increases in swimming speed (1.4% of groups,7.2% of individuals), spy hopping (another behavior to look) (1.8% of groups, 0.7% of individuals), or clearly changing travel direction (2.0% of groups, 0.8% of individuals). No reactions were indications of the animals exhibiting a threat or flee response, but were rather more curiosity or avoidance behaviors commonly seen near vessels in the Arctic (Blees et al. 2010, Hartin et al. 2011, Reider et al. 2013, Cate et al. 2014, Ireland and Bisson 2016). No mitigation was necessary to avoid pinniped interactions.

Table 5-14. Pinniped Groups (Individuals) Observed from All Cable Vessels within the Project Area by Reactionary Behavior

Species None Look Splash Increase Speed Spy Hop Change

Direction Total Bearded Seal 22 (23) 27 (33) 5 (5) - 1 (1) 1 (1) 56 (63) Ringed Seal 59 (65) 28 (30) 6 (6) 2 (3) 2 (2) 4 (4) 101 (110) Spotted Seal 205 (656) 62 (169) 8 (98) 4 (85) 6 (6) 1 (1) 286 (1015) Steller Sea Lion 2 (2) 2(2) - - - - 4 (4) Unidentified Seal 23 (30) 27 (27) 2 (2) 1 (3) - 4 (4) 57 (66)

Total 31 (776) 145 (260) 21 (111) 7 (91) 9 (9) 10 (10) 504 (1258)

5.2.2.6. Pinniped Sighting Rates

Pinnipeds with more than 10 observations – bearded seals, ringed seals, and spotted seals – were included in the following sighting rate calculations.

5.2.2.6.1. Vessel Activity Noise

Spotted seal sighting rates were highest during activities that occurred nearshore, especially those involving the barges (Figure 5-16). Spotted seal sighting rates were highest during nearshore cable-laying and when the barges were at anchor avoiding weather, especially for the Swissco 48 when it spent 30 days working and at idle near Kotzebue spotted seal haulout sites. Sighting rates during tug anchor handling were low consistent with the low level of effort during this activity. One ringed seal and one spotted seal were observed during usable conditions from the cable ships while cable laying with the plow (resulting in low sighting rates). Cable laying with the plow generally occurred farther offshore than where the barges operated (and seals were more prevalent).



Figure 5-16. Pinniped Sighting Rates by Vessel Noise Activity

5.2.2.6.2. Sea State

For bearded and ringed seals, sighting rates generally decline from sea state 1 to 5 due to poorer viewing conditions as sea states increase (Figure 5-17). Low sighting rates for sea state 0 reflects the very low effort that occurred during these rare conditions. The spotted seal sighting rates reflect less the poorer ability to see seals under higher sea states, and more the actual effort that occurred during these sea states. Many of the spotted seals were encountered from barges that lay idle, or were moving very slowly, near spotted seal haulouts (or otherwise high use areas). Because the barges remained at the same location for long periods, seals at those locations were eventually detected regardless of the sea state (due to greater effort for area viewed compared to a faster moving vessel).

Figure 5-17. Pinniped Sighting Rates by Sea State

0.01

1 0.02

7 0.04

1

0.02

5

0.01

1

0.00

9

0.01

1

0.05

7

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7

0.16

2

0.09

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0.12

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0.06

1

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0.18

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Beaufort Sea State

Bearded Seal

Ringed Seal

Spotted Seal

0.02

7

0.03

0

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7

0.00

0 0.01

4 0.02

7

0.00

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0.05

9

0.03

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0.00

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0.03

9

0.00

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0.06

6

0.16

9

0.01

6

0.19

8

0.06

1

0.00

0.05

0.10

0.15

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0.25

Cable Laying,Plow In

Cable SurfaceLay/DP

Cable Laying,Barge

Tug AnchorHandling

Idle-Anchor Transit

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Bearded Seal

Ringed Seal

Spotted Seal




Fog, mist, rain, and snow have an effect on the ability of PSOs to detect these small body seals (Figure 5-18). Fog encountered by the PSOs was generally intermittent with patches of clear areas, allowing some opportunities to detect seals. However, mist, rain, and falling snow generally concealed the viewing area in all directions leading to very low sighting rates.

Figure 5-18. Pinniped Sighting Rates by Precipitation


Bearded, ringed, and spotted seals are relatively small bodied which are more easily identified at distance when viewing conditions are unlimited (≥10 km visibility), as clearly demonstrated in Figure 5-19. The high sighting rates for all three species at visibilities ≥10 km is also reflective of the higher effort that occurred during these visibility conditions.

0.07

7

0.04

8

0.00

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0.00

0

0.00

0

0.12

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0.04

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9

0.00

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0.40

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0.07

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0.45

None Fog Mist Rain Snow

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Precipitation

Bearded Seal

Ringed Seal

Spotted Seal



Figure 5-19. Pinniped Sighting Rates by Visibility


Although ringed and bearded seals are pagophilic, their higher sighting rates when ice is not present is due more to the general low presence of ice near operating vessels, than any selectivity against ice. The especially high sighting rate for spotted seals in areas of zero ice coverage is reflective of the higher densities of spotted seals occurring near the nearshore operations that were purposely conducted after the ice had seasonally retreated (Figure 5-20).

Figure 5-20. Pinniped Sighting Rates by Ice Coverage

0.00

5

0.00

5

0.00

2

0.01

1

0.00

9

0.00

0

0.00

0

0.00

0

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0.00

7

0.00

9

0.07

5

0.01

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0.00

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0.00

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0.01

1

0.00

7

0.12

8

0.00

7

0.01

1

0.01

1

0.01

8

0.03

0

0.00

7

0.00

5

0.00

5

0.00

5

0.01

4

0.00

7

0.39

4

0.000

0.050

0.100

0.150

0.200

0.250

0.300

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0.400

0.450

1 2 3 <3.5 >3.5 4 5 6 7 8 9 ≥10

Sigh

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Visibility (km)

Bearded Seal

Ringed Seal

Spotted Seal

0.10

0

0.01

1

0.00

5

0.00

2

0.00

0

0.00

5

0.00

0

0.00

2

0.00

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0

0.17

3

0.00

5

0.00

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0.00

0

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0.45

8

0.01

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0.50

None <10 10 20 30 40 50 60 70 80

Sigh

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/ 10

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Ice Coverage (%)

Bearded Seal

Ringed Seal

Spotted Seal




Almost 84% of all pinniped sightings occurred from the barges. These vessels operated in nearshore waters at low travel speeds, which accounts for the much higher sighting rates for all pinnipeds when vessels were traveling at <5 kt compared to higher speeds (Figure 5-21). Also, higher speed cable laying (surface laying) and ship transiting occurred in deeper offshore waters where fewer pinniped, in general, were encountered.

Figure 5-21. Pinniped Sighting Rates by Speed Class

Pacific Walrus

Fifty-nine groups (1,194 individuals) of Pacific walrus were observed within the project area (Table 5-15, Appendix H), of which 64.4% of groups (57% of individuals) were recorded from the Ile de Sein and 23.7% of groups (42.3% of individuals) from the CB Networker. Observations from the Ile de Sein ranged in size from 1 to 30 individuals, with the exception of one sighting of 500 animals observed on August 16 when the vessel was in transit. During this sighting the animals were dispersed over several kilometers at a distance (approximately 1,200 m) too great to determine age class.

Table 5-15. Walrus groups (Individuals) Observed from All Cable Vessels within the Project Area

Species Ile de Brehat Ile de Sein CB Networker Swissco 48 Total Pacific Walrus 2 (2) 38 (680) 14 (505) 5 (7)* 59 (1194) * One sighting was reported by the captain of the Dana Cruz (assist tug for the Swissco 48), but no group size or observation detail was provided.

All observations from the CB Networker were during transit periods. PSOs observed 10 groups ranging from 1 to 6 individuals. Four larger sightings were observed with group sizes of 300, 70, and two groups of 50 each. The largest (extended) group of 300 animals was traveling and dispersed over an area of approximately 1 km, while the remaining three groups were observed hauled out on ice at distances between 3.1 and 4.5 km. No walrus reactions to the presence of the CB Networker were noted.

0.114

0.011 0.000

0.175

0.011 0.000

0.503

0.009 0.0000.00

0.10

0.20

0.30

0.40

0.50

0.60

<5 5-10 >10

Sigh

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/ 10

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O E

ffort

Speed Class (kt)

Bearded Seal

Ringed Seal

Spotted Seal



A total of 26 juvenile walruses were recorded in the project area, 20 of which were estimated to be in the large group of 500 noted above. Of the remaining juveniles, two were alone, two were with one other walrus (likely their mother), and two were noted in a group of 15.

5.2.3.1. Sea State

Most in-water walruses (71.4% of groups; 96.5% of individuals) were observed during sea states of 2 or less (Table 5-16), which is probably reflective of both the greater ability to see marine mammals under lower sea state conditions, and the nearby presence of ice that ameliorates wind effects on the sea surface. (The visibility of hauled out walruses is unaffected by sea state.)

Table 5-16. Walrus Groups (Individuals) Observed from All Cable Vessels within the Project Area by Sea State


Total 0 1 2 3 4 5 6 7 8

Pacific Walrus (In Water) 4 (9) 22 (420) 9 (540) 1 (1) 1 (1) 7 (9) 4 (23) - 1 (1) 49 (1004)


Most walruses were observed by vessels in transit within the project area (78% of groups; 98.4% of individuals; Table 5-17), as actual cable-laying operations necessarily avoided ice floes. The high percentage of individual sightings is again due to the large groups associated with sea ice. Approximately 10.2% of walrus groups (0.5% of individuals) were observed during ship cable laying activities with the plow in, while nearly 12% of walrus groups were observed during surface laying activities or use of the DP thrusters (Cable Surface Lay/DP).

Table 5-17. Walrus Groups (Individuals) Observed from All Cable Vessels within the Project Area by Vessel Noise Activity

Species Cable Laying,

Plow In Cable Surface

Lay/DP Cable Laying,

Barge Tug Anchor

Handling Idle,

Anchor Transit Total Pacific Walrus 6 (6) 7 (13) - - - 46

(1175) 59

(1194)


Approximately 83% of walrus groups were observed at a closest approach of 2 km or less (Table 5-18), although all hauled out groups were observed at distances greater than 3 km. Overall, walrus closest points of approach ranged from 1 m to 6,000 m with a mean of 1,038.5 m (s.d. = 1275.3 m). Distance at the end of observation was not recorded in the field because it was requested in the IHA issued after the PSOs had already deployed to the project vessels.



Table 5-18. Walrus Groups (Individuals) Observed from All Cable Vessels within the Project Area by Closest Distance to Vessel

Species

Distance (m)

Total <100 100-500

501-1000

1001-2000

2001-3000

3001-4000

4001-5000

5001-5500 >5500 Unk.

Pacific Walrus

8 (13)

20 (82)

10 (42)

11 (843) 1 (4) 6

(145) 1 (50) - 1 (15) 1

(Unk)*

59 (1194)

*The sighting was reported by the captain of the Dana Cruz (assist tug for the Swissco 48), but no group size or observational data were provided.

5.2.3.4. Behavior

One large group of traveling walrus, observed from the Ile de Sein while transiting, comprised 500 of the 520 animals (96.2%) with the recorded behavior “Surface Active – Travel” (Table 5-19). The animals were dispersed over several kilometers at a distance of over 1.2 km from the ship, making further distinction of smaller groups not possible. Similarly, another large group (300 individuals dispersed over approximately 1 km) of traveling walrus were observed from the CB Networker at over 1.1 km distance from the vessel, limiting details on smaller groups. Three of the more distant (3.1-4.5 km) observations of walrus from the CB Networker were of animals hauled out on ice.

Table 5-19. Walrus Groups (Individuals) Observed from All Cable Vessels within the Project Area by Behavior

Species Look Milling

Hauled Out on

Ice Surface Active

Surface Active

- Travel Travel/Swim Unknown Total Pacific Walrus 8 (26) 3 (22) 10

(190) 5 (17) 10 (520) 22 (419) 1 (Unk)* 59

(1194) *The sighting was reported by the captain of the Dana Cruz (assist tug for the Swissco 48), but no group size or observational data were provided.

5.2.3.5. Pacific Walrus Reactionary Behavior and Mitigation

Approximately 49.2% of walrus observations noted a reactionary behavior; however, none of the reactions were stampedes, but rather minor curiosity or change in direction (Table 5-20). Most commonly, walruses simply stared at the vessel acknowledging its presence. Some in-water animals altered their normal behavior by increasing speed or changing direction as a reaction to the vessel presence or activity, but no animals were recorded demonstrating rushing or fleeing behavior, and none of the hauled-out animals left ice floes.

Table 5-20. Walrus Groups (Individuals) Observed from All Cable Vessels within the Project Area by Reactionary Behavior

Species None Look Splash Increase Speed

Change Direction X Total

Pacific Walrus 30 (633) 12 (520) 3 (5) 5 (24) 8 (12) 1 (Unk)*

59 (1194)

*The sighting was reported by the captain of the Dana Cruz (assist tug for the Swissco 48), but no group size or observational data were provided.



Nearly 90% of walrus sightings did not require mitigation actions, but mitigation (reduction in speed or course alteration) was implemented immediately when requested on six occasions for in-water animals within 600 m of the vessels (five sightings from the Ile de Sein and one from the Swissco 48). Given that none of the walrus reacted in stampedes or extreme reactions, the mitigation efforts proved effective. The mitigation actions are described below.

• August 25: Two walruses were observed at 300 m from the Ile de Sein while the vessel was in transit. A reduction in speed from 9 kt to 5 kt was implemented immediately.

• September 5: Ten walruses (two smaller groups about 75 m apart) were observed swimming near ice at 200 m from the Ile de Sein while the vessel was in transit. A reduction in speed from 7 kt to 5 kt was implemented immediately.

• September 5: A tight group of 10 walruses were observed at 200 m swimming parallel to the Ile de Sein as the vessel passed while in transit. A course alteration away from the animals was implemented.

• September 5: The captain of the Dana Cruz, support tug for the Swissco 48, observed at least one walrus and radioed to the Swissco 48 to alter course to port to avoid the walrus on the starboard side. Both vessels maintained speeds of 5 kt or less as they continued transiting south away from the ice. No additional sighting details were recorded because the animals dove and were never observed by the PSOs.

• October 3: Three walruses were observed at 600 m from the Ile de Sein and a reduction in speed to 5 kt was implemented.

• October 5: During darkness in the early morning, three walruses were observed off the starboard bow of the Ile de Sein at 25 m cued by a splash. A course alteration away from the animals was immediately implanted and the vessel traveled perpendicular to the animal’s path.

5.2.3.6. Pacific Walrus Sighting Rates

Fifty-two groups of Pacific walruses were observed during PSO effort that met the “usable” criteria for sighting rate calculations, ten of which were hauled out on ice and were analyzed separately from those observed in the water.

5.2.3.6.1. Vessel Noise Activities

Approximately 70% of walruses observed during usable effort were in water during transit activity, reflecting the PSO effort when the cable ships were transiting near ice (Figure 5-22).



Figure 5-22. Pacific Walrus Sighting Rates by Vessel Noise Activity

5.2.3.6.2. Sea State

In-water walrus sighting rates were highest during sea state 1, reflective of both the greater ability to detect swimming walrus in lower sea states and the higher presence of lower sea states near sea ice (walrus habitat), which dampens wind effects (Figure 5-23).

Figure 5-23. Pacific Walrus Sighting Rates by Sea State

0.0050.009 0.0090.009

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0.082

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Pacific Walrus (In water)

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Regardless of whether walruses were in the water or hauled out on ice, their sighting rate declined during periods of fog and snow (Figure 5-24). Sighting rates were much higher for in-water walruses than those hauled out, which is reflective of much fewer numbers of groups (although higher number of individuals) when walrus haul out and congregate. The relatively high sighting rates for in-water walrus during foggy conditions may be a result of naturally high fog conditions encountered near sea ice (walrus habitat). Ice edge fog occurs when warmer air over the sea surface is mixes with the colder air over the sea ice causing moisture in the air to condense and form fog.

Figure 5-24. Pacific Walrus Sighting Rates by Precipitation


Sighting rates of both in-water and on-ice walruses were greater when visibility was unlimited (≥10 km), which was expected (Figure 5-25). The relatively high sighting rates during poor visibility conditions (1 and 2 km) may be due to the foggy conditions occurring near ice when many of the walrus were encountered.

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Figure 5-25. Pacific Walrus Sighting Rates by Visibility


Compared to other marine mammals, higher sighting rates of walrus occurred in various sea ice conditions, reflective of the pagophilic nature of this marine mammal (Figure 5-26). Walruses hauled out on ice, of course, have higher sighting rates associated with sea ice. While many of the in-water walrus were recorded when no sea ice was present, high sighting rates did occur when there was low ice coverage.

Figure 5-26. Pacific Walrus Sighting Rates by Ice Coverage

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Many of the walruses observed during the cable-lay program were recorded during periods when vessels were transiting between Wainwright and Barrow. When enough ice was encountered to support hauled out walrus, the vessels had either slowed down or stopped, either to avoid ice collisions or to avoid disturbing the hauled-out walrus (Figure 5-27).

Figure 5-27. Pacific Walrus Sighting Rates by Speed Class

Polar Bears

Polar bears were observed from the Ile de Sein and CB Networker when the vessels were operating in the Beaufort Sea (Table 5-21, Appendix H). No sightings occurred in either the Bering or Chukchi seas, or from the other two vessels. The single Ile de Sein sighting occurred approximately 80 km northwest of Oliktok Point. While the ship was stationary, intermittently using thrusters to maintain position, a curious bear swam up to the ship where it remained for about an hour (swimming back and forth along the ship length) before eventually swimming away. Two sightings from the CB Networker were of bears on Spy Island when the vessel was conducting pre-trenching operations approximately 3 km to 4.5 km away. The remaining sightings occurred at either Thetis Island or Cross Island when the vessel was there to take shelter from bad weather. Since the vessel was often anchored off the islands for several days, it is possible that some bears were recorded on multiple occasions. None of the bears observed from the CB Networker reacted to the vessel presence.

Table 5-21. Polar Bear Groups (Individuals) Observed from All Cable Vessels within the Project Area.

Species Ile de Brehat Ile de Sein CB Networker Swissco 48 Total Polar Bear - 1 (1) 7 (12) - 8 (13)

0.023

0.000 0.000

0.036

0.043

0.016

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The one polar bear observed from the Ile de Sein occurred while the vessel was idle with DP thrusters engaged to hold position (Table 5-22). The remaining sightings occurred from the CB Networker while it was on anchor or in transit to or from a weather respite location.

Table 5-22. Polar Bear Groups (Individuals) Observed from All Cable Vessels within the Project Area by Vessel Noise Activity

Species Cable

Laying, Plow In

Cable Surface Lay

/ DP

Cable Laying, Barge

Tug Anchor

Handling

Idle, Anchor Transit Total

Polar Bear - 1 (1) - - 5 (9) 2 (3) 8 (13)


Four sightings of nine individuals recorded from the CB Networker were observed at CPAs of over 3 km. Other observations from the CB Networker included one bear in each CPA category: 100-500 m, 1,000-2,000 m, and 2,001-3,000 m. The polar bear observed from the Ile de Sein approached the vessel to 5 m at closest approach. The mean CPA for polar bears across both vessels was 2,133.5 m (s.d. = 1,322.9 m; range: 5.0-3,124.0 m).

5.2.4.3. Polar Bear Behavior

The single bear observed from the Ile de Sein was actively looking at the vessel while it swam. All other polar bear observations were from the CB Networker of bears on or near barrier islands while the vessel was in the area primarily seeking refuge from bad weather. Behaviors observed from the CB Networker included milling, traveling, swimming, and walking.

5.2.4.4. Polar Bear Reactionary Behavior and Mitigation

Seven of the 8 sightings, or 87.5% of polar bears observed within the project area did not exhibit any reactionary behavior, likely due to their distance from the vessel and the fact most were on land. Also, no mitigation was necessary for any of the polar bear sightings from the CB Networker. The single bear observed from the Ile de Sein did approach, look, sniff, and then eventually change direction to swim away from the vessel. This swimming bear was obviously interested in the vessel, possibly seeking a platform to rest. The vessel was already idle; therefore, no additional mitigation was implemented.

Carcasses

Seven carcasses (Table 5-23) were observed by PSOs and recorded within the project area, none of which were able to be confidently identified to species due to distance or decomposition status. None of the carcasses were as a result of project activities and all were reported according to the NMFS and USFWS requirements. Two carcasses in close proximity observed from the Swissco 48 were likely the result of predation based on the observations of killer whales nearby. They were observed at a distance too great (approximately 2 km) to confidently determine if the carcasses represented two animals or only one animal in two pieces. In addition, vessel crews onboard two other project vessels (Dana Cruz and Norman O) reported carcass sightings to the PSOs. These reports were also submitted to NMFS and USFWS. All carcass reports submitted to the agencies are in Appendix I.



Table 5-23. Carcasses (Individuals) Recorded per Vessel

Species Ile de Brehat Ile de Sein CB Networker Swissco 48 Total Carcasses 3 (3) - 2 (2) 2 (3) 7 (8)

5.3. Animals Potentially Affected Cable installation generated various levels of noise based on the type of activity being conducted, thus various noise thresholds (zones) were measured to determine the number of potentially affected marine mammals (Table 4-3; Section 4.2.2.2). Marine mammals, except walrus, that entered an active 120-dB Level B harassment zone were considered potentially exposed. Walrus were considered acoustically exposed when they entered an active 160-dB Level B zone.

Cetaceans

Table 5-24 highlights the number of cetaceans observed within the 120-dB harassment zone. Several unidentified whales were observed within these zones; however, most were likely gray whales based on their locations and associated sightings. Authorized take was not exceeded for any of the cetacean species.

Table 5-24. Cetaceans (Individuals) Potentially Exposed to Sound Levels Exceeding 120 dB

Pinnipeds

Table 5-25 shows the number of pinnipeds observed within the 120-dB harassment zone. It is likely that most of the unidentified seals observed during cable laying from the barge were spotted seals because they were observed from the Swissco 48 while operating near Kotzebue. Ten seals, recorded as multiple species (including one probable bearded seal and the rest unidentified seals), were observed within the 2.3-km radius 120-dB zone from the Ile de Brehat while using DP. These animals are summarized in Table 5-25 as unidentified seals. In no case was authorized take exceeded.

Species Authorized

Level B Take

Vessel Activity (Dist. To 120 dB Threshold) Total Cable

Laying, Plow In

(5.35 km)

Tug Anchor Handling (5.13 km)


(2.30 km)

Cable Laying, Barge

(1.23 km)

Bowhead Whale 130 2 - 47 14 63 Fin Whale 15 2 - 1 - 3 Gray Whale 572 40 - 109 4 153 Harbor Porpoise 16 - - 12 1 13 Humpback Whale 62 - - 39 - 39 Killer Whale 5 1 - - - 1 Minke Whale 5 - - 1 - 1 Unidentified Mysticete - 16 2 9 10 37 Unidentified Porpoise - - - - - 0 Unidentified Whale - 6 - 8 - 14



Table 5-25. Pinnipeds (Individuals) Potentially Exposed to Sound Levels Exceeding 120 dB

Species Authorized Level B Take

Vessel Activity (Dist. To 120 dB Threshold) Total

Cable Laying, Plow In

(5.35 km)

Tug Anchor Handling (5.13 km)

Cable Surface Lay / DP

(2.30 km)

Cable Laying, Barge

(1.23 km)

Bearded Seal 475 15 - 15 11 41 Ringed Seal 992 1 1 32 16 50 Spotted Seal 325 - 24 27 118 169 Steller Sea Lion 8 3 - - - 3 Unidentified Seal - 10 1 78 61 140

Walrus

Only one walrus was recorded to within 29 m of an active cable-laying ship and, thus, was the only walrus potentially exposed to underwater sounds exceeding Level B harassment thresholds. The walrus voluntarily approached the ship, which was moving at a speed well less than 1 kt. Based on this single Level B take, project activities did not have significant impacts on walrus.

Polar Bear

One polar bear swam to the Ile de Sein while the ship was stopped and maintaining position by intermittent use of its thrusters. This sighting was immediately reported to the USFWS and no further action was required.

5.4. Summary and Conclusions In 2016, Quintillion initiated a fiber-optic cable installation project in Arctic Alaska that, when complete, will connect five villages (Nome, Kotzebue, Point Hope, Wainwright, and Barrow) and Oliktok Point with high speed internet service. Ninety-six percent of the 1,904-km (1,183-mi) route was laid in 2016, with the remaining 76 km (47 mi) to be completed in summer of 2017. The 2016 program involved two cable-lay ships (Ile de Brehat and Ile de Sein) and two cable-lay barges (Swissco 48 and CB Networker). As stipulated in the IHAs from both NMFS and USFWS, PSOs were onboard each of the four cable vessels from which they monitored for marine mammals.

Within the project area, defined as all the cable routes between Nome and Oliktok Point (or north of 64°N), PSOs recorded 810 groups composed of 3,041 individuals representing 13 species (bowhead whale, fin whale, humpback whale, minke whale, gray whale, killer whale, harbor porpoise, bearded seal, ringed seal, spotted seal, Steller sea lion, Pacific walrus, and polar bear). In addition, PSOs recorded 48 groups of 110 individual marine mammals during cable ship transits between Dutch Harbor and Nome. Seven species (fin whale, humpback whale, Dall’s porpoise, harbor porpoise, northern fur seal, Steller sea lion, and sea otter) were recorded during these transits across the Bering Sea. There is a clear subarctic vs Arctic distinction in the species composition when comparing the more southern transit routes with the cable routes within the project area. However, six species typically defined as “subarctic” were recorded in the project area including fin whales (5 animals), humpback whales (39 animals), minke whales (5 animals), killer whales (19 animals), harbor porpoises (45 animals), and Steller sea lions (4 animals).



The most unusual sighting was of an extended group of at least 36 humpback whales at the north end of the Bering Strait near Wales. Humpback whale use in the Arctic waters of Alaska has been increasing (Clarke et al. 2013), but the number of whales observed during this project was unexpected. Also unexpected were four observations of “subarctic” Steller sea lions. One Steller sea lion was positively resighted, based on a distinct marking on its head, 10 days after first observation, resulting in four separate sightings of three animals.

The most commonly observed marine mammal was the spotted seal, with 286 groups of 1,015 seals recorded in the project area. However, these numbers were inflated by repeated sightings of spotted seals near Kotzebue. The cable barge Swissco 48 operated intermittently near Kotzebue for approximately a month, and PSOs onboard were consistently observing spotted seals moving to and from nearby haulout sites. More than half of all spotted seal sightings occurred at Kotzebue.

Other species, including bowhead whales, gray whales, Pacific walruses, and polar bears were found at expected locations. Bowhead whales were found in typical summer feeding waters or fall migration routes around Point Barrow, while gray whales were most common at their recognized feeding grounds in the Chukchi Sea. Walruses were nearly always associated with sea ice, while polar bears were mostly observed wandering the Beaufort Sea barrier islands.

In no case did the number of animals that were observed inside an active harassment zone exceed the authorized harassment take. For “Arctic” species the percentage of animals taken compared to authorized takes ranged from <1% (walrus) to 52% (spotted seal), but noting that spotted seal numbers were inflated due to the Swissco 48 spending nearly a month near Kotzebue seal haulout sites. The percentage of authorized take for all other species was 37% (bowhead whale) or less. For “subarctic” species the percentages ranged higher from 20% (minke whale and killer whale) to 81% (harbor porpoise) due largely to underestimating the number of “subarctic” species and individuals that might be encountered in the Arctic (the NMFS IHA was amended on 27 September 2016 to account for unexpected sightings of humpback whales and Steller sea lions). In 2016, summer sea surface temperatures in the Chukchi Sea were again at record levels with mean temperatures 7°C to 8°C above baseline (Timmermans 2017), with trends suggesting continued warming into the future. Future harassment authorizations may need to account for increased summer use of the Arctic by “subarctic” species.



6. LITERATURE CITED

Blees, M.K., K.G. Hartin, D.S. Ireland, and D. Hannay. (eds.) 2010. Marine mammal monitoring and mitigation during open water seismic exploration by Statoil USA E&P Inc. in the Chukchi Sea, August–October 2010: 90-day report. LGL Rep. P1119. Rep. from LGL Alaska Research Associates Inc., LGL Ltd., and JASCO Research Ltd. for by Statoil USA E&P Inc., Nat. Mar. Fish. Serv., and U.S. Fish and Wild. Serv. 102 pp, plus appendices.

Castellote, M., C.L. Berchok, S.L. Grassia, and J.L. Crance. 2017. Passive Acoustical Monitoring – Quintillion Cable-Laying Project. Draft Report for Quintillion. January 2017. 36 p.

Cate, J.R., M. Smultea, M. Blees, M. Larson, S. Simpson, T. Jefferson and D. Steckler. 2014. 90-Day Report of Marine Mammal Monitoring and Mitigation during a 2D Seismic Survey by TGS in the Chukchi Sea, August through October 2013. AES Doc. No. 15416-04 13-185. Prepared by ASRC Energy Services, Smultea Environmental Sciences, Clymene Enterprises and Entiat River Technologies for TGS-NOPEC Geophysical Company, National Marine Fisheries Service and U.S. Fish and Wildlife Service. 122 p. + Appendices.

Clarke, J., K. Stafford, S.E. Moore, B. Rone, L. Aerts, and J. Crance. 2013. Subarctic cetaceans in the southern Chukchi Sea: Evidence of recovery or response to a changing ecosystem. Oceanography 26(4):136–149

Clarke, J.T., A.A. Brower, M.C. Ferguson, A.S. Kennedy, and A.L. Willoughby. 2015. Distribution and Relative Abundance of Marine Mammals in the Eastern Chukchi and Western Beaufort Seas, 2014. Annual Report, OCS Study BOEM 2015-040. National Marine Mammal Laboratory, Alaska Fisheries Science Center, NMFS, NOAA, 7600 Sand Point Way NE, F/AKC3, Seattle, WA 98115-6349.

Hannay, D., A. MacGillivray, M. Laurinolli, and R. Racca. 2004. Sakhalin Energy: Source Level Measurements from 2004 Acoustics Program, Ver. 1.5. Technical report prepared for Sakhalin Energy by JASCO Research Ltd., December 2004.

Hartin K.G., L.N. Bisson, S.A. Case, D.S. Ireland, and D. Hannay. (eds.) 2011. Marine mammal monitoring and mitigation during site clearance and geotechnical surveys by Statoil USA E&P Inc. in the Chukchi Sea, August–October 2011: 90-day report. LGL Rep. P1193. Rep. from LGL Alaska Research Associates Inc., LGL Ltd., and JASCO Research Ltd. for Statoil USA E&P Inc., Nat. Mar. Fish. Serv., and U.S. Fish and Wild. Serv. 202 pp, plus appendices.

Ireland, D.S. and L.N. Bisson. (eds.) 2016. Marine mammal monitoring and mitigation during exploratory drilling by Shell in the Alaskan Chukchi Sea, July–October 2015: 90-Day Report. LGL Rep. P1363D. Rep. from LGL Alaska Research Associates Inc., Anchorage, AK, USA, and JASCO Applied Sciences, Victoria, BC, Canada, for Shell Gulf of Mexico Inc, Houston, TX, USA, Nat. Mar. Fish. Serv., Silver Spring, MD, USA, and U.S. Fish and Wild. Serv., Anchorage, AK, USA. 188 pp, plus appendices.



Nelson, C.H, R.L. Phillips, J. McRea, Jr., J.H. Barber, Jr., M.W., McLaughlin, and J.L. Chin. 1994. Gray whale and Pacific walrus benthic feeding grounds and sea floor interaction in the Chukchi Sea. U.S. Gological Survey, Menlo Park, California, 94025. OCS Study MMS 93-0042.

Pommerenck, K. and J. Reyff. 2016. Quintillion Subsea Operations Fiber Optic Cable-Laying Project Sound Source Verification – Nome Alaska. Report prepared by Illingworth & Rodkin, Inc for Owl Ridge Natural Resource Consultants, Inc. Job No.: 16-120.

Quakenbush, L. T., R. J. Small, and J. J. Citta. 2013. Satellite tracking of bowhead whales: movements and analysis from 2006 to 2012. (PDF 3,635 kB) U.S. Dept. of the Interior, Bureau of Ocean Energy Management, Alaska Outer Continental Shelf Region, Anchorage, AK. OCS Study BOEM 2013-01110. 56 pp.

Reider, H.J., L.N. Bisson, M. Austin, A. McCrodan. J. Wladichuk, C.M. Reiser, K.B. Matthews, J.R. Brandon, K. Leonard, and H.M. Patterson. 2013. Marine mammal monitoring and mitigation during Shell’s activities in the Chukchi Sea, July–September 2013: Draft 90-Day Report. LGL Report P1272D–2. Report from LGL Alaska Research Associates Inc., Anchorage, AK, USA, and JASCO Applied Sciences, Victoria, BC, Canada, for Shell Gulf of Mexico, Houston, TX, USA, National Marine Fisheries Service, Silver Spring, MD, USA, and U.S. Fish and Wildlife Service, Anchorage, AK, USA. 198 pp, plus appendices.

Timmermans, M.-L. 2017. Sea Surface Temperature. In: Arctic Report Card 2016; http://www.arctic.noaa.gov/Report-Card.

Whiting, A., D. Griffith, S. Jewett, L. Clough, W. Ambrose, and J. Johnson. 2011. Combining Iñupiaq and Scientific Knowledge: Ecology in Northern Kotzebue Sound, Alaska. Fairbanks: Alaska Sea Grant College Program, 2011. doi:10.4027/ciskenksa.

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