504 Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 

DEPARTMENT OF COMMERCE 

National Oceanic and Atmospheric 

Administration 

50 CFR Part 217 

[Docket No. 231206–0289] 

RIN 0648–BM32 

Takes of Marine Mammals Incidental to 

Specified Activities; Taking Marine 

Mammals Incidental to the Maryland 

Offshore Wind Project Offshore of 

Maryland 

AGENCY: National Marine Fisheries 

Service (NMFS), National Oceanic and 

Atmospheric Administration (NOAA), 

Commerce. 

ACTION: Proposed rule; request for 

comments. 

SUMMARY: NMFS has received a request 

from US Wind, Inc., (US Wind) for 

Incidental Take Regulations (ITR) and 

an associated Letter of Authorization 

(LOA) pursuant to the Marine Mammal 

Protection Act (MMPA). The requested 

regulations would govern the 

authorization of take, by Level A 

harassment and Level B harassment, of 

small number of marine mammals over 

the course of 5 years (2025–2029) 

incidental to construction of the 

Maryland Offshore Wind Project 

offshore of Maryland within the Bureau 

of Ocean Energy Management (BOEM) 

Commercial Lease of Submerged Lands 

for Renewable Energy Development on 

the Outer Continental Shelf (OCS) Lease 

Area OCS–A 0490 (Lease Area) and 

associated Export Cable Routes. Project 

activities likely to result in incidental 

take include impact pile driving and site 

assessment surveys using highresolution geophysical (HRG) 

equipment. NMFS requests comments 

on its proposed rule. NMFS will 

consider public comments prior to 

making any final decision on the 

promulgation of the requested ITR and 

issuance of the LOA; agency responses 

to public comments will be summarized 

in the final notice of our decision. The 

proposed regulations, if issued, would 

be effective January 1, 2025 through 

December 31, 2029. 

DATES: Comments and information must 

be received no later than February 5, 

2024. 

ADDRESSES: Submit all electronic public 

comments via the Federal e-Rulemaking 

Portal. Go to https://

www.regulations.gov and enter NOAA– 

NMFS–2023–0110 in the Search box. 

(note: copying and pasting the FDMS 

Docket Number directly from this 

document may not yield search results). 

Click on the ‘‘Comment’’ icon, complete 

the required fields, and enter or attach 

your comments. 

Instructions: Comments sent by any 

other method, to any other address or 

individual, or received after the end of 

the comment period, may not be 

considered by NMFS. All comments 

received are a part of the public record 

and will generally be posted for public 

viewing on https://www.regulations.gov 

without change. All personal identifying 

information (e.g., name, address), 

confidential business information, or 

otherwise sensitive information 

submitted voluntarily by the sender will 

be publicly accessible. NMFS will 

accept anonymous comments (enter ‘‘N/ 

A’’ in the required fields if you wish to 

remain anonymous). 

FOR FURTHER INFORMATION CONTACT: 

Jessica Taylor, Office of Protected 

Resources, NMFS, (301) 427–8401. 

SUPPLEMENTARY INFORMATION: 

Availability 

A copy of US Wind’s Incidental Take 

Authorization (ITA) application and 

supporting documents, as well as a list 

of the references cited in this document, 

may be obtained online at: https://

www.fisheries.noaa.gov/national/ 

marine-mammal-protection/incidentaltake-authorizations-other-energyactivities-renewable. In case of problems 

accessing these documents, please call 

the contact listed above (see FOR

FURTHER INFORMATION CONTACT). 

Purpose and Need for Regulatory 

Action 

This proposed rule would provide a 

framework under the authority of the 

MMPA (16 U.S.C. 1361 et seq.) to allow 

for the authorization of take of marine 

mammals incidental to construction of 

the Maryland Offshore Wind Project 

(hereafter, ‘‘Project’’) within the BOEM 

Renewable Energy Development Lease 

Area and along export cable corridors to 

landfall locations in Delaware. NMFS 

received a request from US Wind for 5- 

year regulations and a LOA that would 

authorize take of individuals of 19 

species of marine mammals (5 species 

by Level A harassment and Level B 

harassment and 14 species by Level B 

harassment only), comprising 20 stocks, 

incidental to US Wind’s construction 

activities. No mortality or serious injury 

is anticipated or proposed for 

authorization. Please see below for 

definitions of harassment. Please see the 

Estimated Take of Marine Mammals 

section below for definitions of relevant 

terms. 

Legal Authority for the Proposed Action 

The MMPA prohibits the ‘‘take’’ of 

marine mammals, with certain 

exceptions. Sections 101(a)(5)(A) and 

(D) of the MMPA (16 U.S.C. 1361 et 

seq.) direct the Secretary of Commerce 

(as delegated to NMFS) to allow, upon 

request, the incidental, but not 

intentional, taking of small numbers of 

marine mammals by U.S. citizens who 

engage in a specified activity (other than 

commercial fishing) within a specified 

geographical region if certain findings 

are made, regulations are promulgated 

(when applicable), and public notice 

and an opportunity for public comment 

are provided. 

Authorization for incidental takings 

shall be granted if NMFS finds that the 

taking will have a negligible impact on 

the species or stock(s) and will not have 

an unmitigable adverse impact on the 

availability of the species or stock(s) for 

taking for subsistence uses (where 

relevant). Further, NMFS must prescribe 

the permissible methods of taking and 

other ‘‘means of effecting the least 

practicable adverse impact’’ on the 

affected species or stocks and their 

habitat, paying particular attention to 

rookeries, mating grounds, and areas of 

similar significance, the availability of 

the species or stocks for taking for 

certain subsistence uses (referred to as 

‘‘mitigation’’), and requirements 

pertaining to the mitigation, monitoring 

and reporting of the takings are set forth. 

As noted above, no serious injury or 

mortality is anticipated or proposed for 

authorization in this proposed rule. 

Relevant definitions of MMPA statutory 

and regulatory terms are included 

below: 

• Citizen—individual U.S. citizens or 

any corporation or similar entity if it is 

organized under the laws of the United 

States or any governmental unit defined 

in 16 U.S.C. 1362(13) (50 CFR 216.103); 

• Take—to harass, hunt, capture, or 

kill, or attempt to harass, hunt, capture, 

or kill any marine mammal (16 U.S.C. 

1362; 50 CFR 216.3); 

• Incidental taking—an accidental 

taking. This does not mean that the 

taking is unexpected, but rather it 

includes those takings that are 

infrequent, unavoidable, or accidental 

(50 CFR 216.103); 

• Serious injury—any injury that will 

likely result in mortality (50 CFR 216.3); 

• Level A harassment—any act of 

pursuit, torment, or annoyance which 

has the potential to injure a marine 

mammal or marine mammal stock in the 

wild (16 U.S.C. 1362); and 

• Level B harassment—any act of 

pursuit, torment, or annoyance which 

has the potential to disturb a marine 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 505 

mammal or marine mammal stock in the 

wild by causing disruption of behavioral 

patterns, including, but not limited to, 

migration, breathing, nursing, breeding, 

feeding, or sheltering (16 U.S.C. 1362). 

Section 101(a)(5)(A) of the MMPA and 

the implementing regulations at 50 CFR 

part 216, subpart I, provide the legal 

basis for proposing and, if appropriate, 

issuing 5-year regulations and 

associated LOA. This proposed rule also 

establishes required mitigation, 

monitoring, and reporting requirements 

for US Wind’s activities. 

Summary of Major Provisions Within 

the Proposed Action 

The major provisions within this 

proposed rule are as follows: 

• Authorize take of marine mammals 

by Level A harassment and/or Level B 

harassment; 

• No mortality or serious injury of 

any marine mammal is proposed to be 

authorized; 

• Establish a seasonal moratorium on 

pile driving during the months of 

highest North Atlantic right whale 

(Eubalaena glacialis) presence in the 

project area (December 1–April 30); 

• Require both visual and passive 

acoustic monitoring by trained, NMFSapproved Protected Species Observers 

(PSOs) and Passive Acoustic Monitoring 

(PAM) operators before, during, and 

after impact pile driving and HRG 

surveys; 

• Require training for all US Wind 

personnel that would clearly articulate 

all relevant responsibilities, 

communication procedures, marine 

mammal monitoring and mitigation 

protocols, reporting protocols, safety, 

operational procedures, and 

requirements of the ITA and ensure that 

all requirements are clearly understood 

by all participating parties; 

• Require the use of sound 

attenuation device(s) during all 

foundation installation activities to 

reduce noise levels; 

• Delay the start of foundation 

installation if a North Atlantic right 

whale is observed at any distance by a 

PSO or acoustically detected within 

certain distances; 

• Delay the start of foundation 

installation if other marine mammals 

are observed entering or within their 

respective clearance zones; 

• Shut down pile driving (if feasible) 

if a North Atlantic right whale is 

observed or if other marine mammals 

enter their respective shut down zones; 

• Shut down HRG survey equipment 

that may impact marine mammals if a 

marine mammal enters their respective 

shut down zones; 

• Conduct sound field verification 

during impact pile driving to ensure in 

situ noise levels are not exceeding those 

modeled; 

• Implement soft starts for impact 

pile driving; 

• Implement ramp-up for HRG site 

characterization survey equipment; 

• Increase awareness of North 

Atlantic right whale presence through 

monitoring of the appropriate networks 

and very high-frequency (VHF) Channel 

16, as well as reporting any sightings to 

the sighting network; 

• Implement various vessel strike 

avoidance measures; 

• Implement Best Management 

Practices (BMPs) during fisheries 

monitoring surveys, such as removing 

gear from the water if marine mammals 

are considered at-risk or are interacting 

with gear; and 

• Require frequent scheduled and 

situational reporting including, but not 

limited to, information regarding 

activities occurring, marine mammal 

observations and acoustic detections, 

and sound field verification monitoring 

results. 

Under section 105(a)(1) of the MMPA, 

failure to comply with these 

requirements or any other requirements 

in a regulation or permit implementing 

the MMPA may result in civil monetary 

penalties. Pursuant to 50 CFR 216.106, 

violations may also result in suspension 

or withdrawal of the LOA for the 

project. Knowing violations may result 

in criminal penalties under section 

105(b) of the MMPA. 

National Environmental Policy Act 

(NEPA) 

To comply with the National 

Environmental Policy Act of 1969 

(NEPA) (42 U.S.C. 4321 et seq.) and 

NOAA Administrative Order (NAO) 

216–6A, NMFS must evaluate the 

proposed action (i.e., promulgation of 

regulations and subsequent issuance of 

a 5-year LOA) and alternatives with 

respect to potential impacts on the 

human environment. 

Accordingly, NMFS plans to adopt 

the BOEM Environmental Impact 

Statement (EIS), provided our 

independent evaluation of the 

document finds that it includes 

adequate information analyzing the 

effects of promulgating the proposed 

regulations and LOA issuance on the 

human environment. NMFS is a 

cooperating agency on BOEM’s EIS. 

BOEM’s draft EIS, ‘‘Maryland Offshore 

Wind Project Draft Environmental 

Impact Statement (DEIS) for Commercial 

Wind Lease OCS–A 0490’’, was made 

available for public comment on 

October 6, 2023 (88 FR 69658) and is 

available at https://www.boem.gov/ 

renewable-energy/state-activities/ 

maryland-offshore-wind. The DEIS had 

a 45-day public comment period open 

from October 6, 2023 to November 20, 

2023. Additionally, BOEM held two inperson public meetings on October 24, 

2023 in Ocean City, Maryland and 

October 26, 2023 in Dagsboro, Delaware 

and two virtual public meetings on 

October 19, 2023 and October 30, 2023. 

Information contained within US 

Wind’s ITA application and this Federal 

Register document provide the 

environmental information related to 

these proposed regulations and 

associated 5-year LOA for public review 

and comment. NMFS will review all 

comments submitted in response to this 

notice of proposed rulemaking prior to 

concluding the NEPA process or making 

a final decision on the requested 5-year 

ITR and LOA. 

Fixing America’s Surface 

Transportation Act (FAST–41) 

This project is covered under Title 41 

of the Fixing America’s Surface 

Transportation Act, or ‘‘FAST–41.’’ 

FAST–41 includes a suite of provisions 

designed to expedite the environmental 

review for covered infrastructure 

projects, including enhanced 

interagency coordination as well as 

milestone tracking on the public-facing 

Permitting Dashboard. FAST–41 also 

places a 2-year limitations period on 

any judicial claim that challenges the 

validity of a Federal agency decision to 

issue or deny an authorization for a 

FAST–41 covered project (42 U.S.C. 

4370m–6(a)(1)(A)). 

US Wind’s proposed project is listed 

on the Permitting Dashboard. 

Milestones and schedules related to the 

environmental review and permitting 

for the US Wind’s Maryland Offshore 

Wind Project can be found at https://

www.permits.performance.gov/ 

permitting-project/maryland-offshorewind-project. 

Summary of Request 

On August 31, 2022, NMFS received 

a request from US Wind, a Baltimore, 

Maryland-based company registered in 

the State of Delaware and subsidiary of 

Renexia SpA, for the promulgation of 

regulations and issuance of an 

associated 5-year LOA to take marine 

mammals incidental to construction 

activities associated with 

implementation of the Project offshore 

of Maryland in the BOEM Lease Area 

OCS–A 0490 and associated export 

cable routes. The request was for the 

incidental, but not intentional, taking of 

a small number of 19 marine mammal 

species (comprising 20 stocks). Neither 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
506 Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 

US Wind nor NMFS expects serious 

injury or mortality to result from the 

specified activities nor is any proposed 

for authorization. 

US Wind is proposing to develop the 

Project over the course of three 

construction campaigns. In total, the 3 

campaigns would result in a maximum 

of 114 wind turbine generators (WTGs), 

4 offshore substations (OSS) positions, 

and 1 Meteorological tower (Met tower) 

within the Lease Area. The initial 

construction campaign, MarWin, would 

include installation of approximately 21 

WTGs, 1 OSS, and cable landing 

infrastructure during the first year of 

activities in the most eastern part of the 

Lease Area. The second construction 

campaign, Momentum Wind, would 

take place during the second year of 

construction activities and include 

installation of approximately 55 WTGs, 

2 OSSs, and a Met tower immediately to 

the west of MarWin. The third 

construction campaign, currently 

unnamed and referred to as Future 

Development, would occur during the 

third year of construction activities and 

include the installation of 

approximately 38 WTGs and 1 OSS in 

the most western portion of the Lease 

Area. Four offshore export cables would 

transmit electricity generated by the 

WTGs from the Lease Area to onshore 

transmission systems within Delaware 

Seashore State Park. 

In response to our comments and 

following extensive information 

exchanges with NMFS, US Wind 

submitted a final, revised application on 

March 31, 2023 that NMFS deemed 

adequate and complete on April 3, 2023. 

The final version of the application is 

available on NMFS’ website at: https:// 

www.fisheries.noaa.gov/action/ 

incidental-take-authorization-us-windinc-construction-and-operationmaryland-offshore-wind. On May 2, 

2023, NMFS published a notice of 

receipt (NOR) of the adequate and 

complete application in the Federal 

Register (88 FR 27463), requesting 

comments and soliciting information 

related to US Wind’s request during a 

30-day public comment period. During 

the NOR public comment period, NMFS 

received comment letters from 77 

private citizens, 6 non-governmental 

organizations, and 1 state government 

organization (Delaware Department of 

Natural Resources and Environmental 

Control). NMFS has reviewed all 

submitted material and has taken these 

into consideration during the drafting of 

this proposed rule. 

On August 1, 2022, NMFS announced 

proposed changes to the existing North 

Atlantic right whale vessel speed 

regulations (87 FR 46921, August 1, 

2022) to further reduce the likelihood of 

mortalities and serious injuries to 

endangered right whales from vessel 

collisions, which are a leading cause of 

the species’ decline and a primary factor 

in an ongoing Unusual Mortality Event 

(UME). Should a final vessel speed rule 

be issued and become effective during 

the effective period of this ITR (or any 

other MMPA incidental take 

authorization), the authorization holder 

would be required to comply with any 

and all applicable requirements 

contained within the final rule. 

Specifically, where measures in any 

final vessel speed rule are more 

protective or restrictive than those in 

this or any other MMPA authorization, 

authorization holders would be required 

to comply with the requirements of the 

rule. Alternatively, where measures in 

this or any other MMPA authorization 

are more restrictive or protective than 

those in any final vessel speed rule, the 

measures in the MMPA authorization 

would remain in place. The 

responsibility to comply with the 

applicable requirements of any vessel 

speed rule would become effective 

immediately upon the effective date of 

any final vessel speed rule and when 

notice is published on the effective date, 

NMFS would also notify US Wind if the 

measures in the speed rule were to 

supersede any of the measures in the 

MMPA authorization such that they 

were no longer required. 

On September 6, 2023, and September 

11, 2023, US Wind submitted 

supplemental information related to its 

pilot whale and seal take analyses. The 

corresponding memos, entitled ‘‘US 

Wind NMFS Request for Information 

(RFI) Response Memo and Maryland 

Offshore Wind Project Revised 

Requested Take Tables’’ are available on 

our website. 

Description of the Specified Activities 

Overview 

US Wind has proposed to construct 

and operate a wind energy facility, the 

Project, in the Atlantic Ocean in lease 

area OCS–A 0490, offshore Maryland. 

The Project would allow the State of 

Maryland to advance Federal and State 

offshore wind targets as well as reduce 

greenhouse gas emissions, increase grid 

reliability, and support economic 

development growth in the region. The 

Project consists of three construction 

campaigns including MarWin, located 

in the southeastern portion of the Lease 

Area with the potential to generate 

approximately 300 megawatts (MW) of 

energy, Momentum Wind, located 

immediately west of MarWin with the 

potential to generate approximately 808 

MW of energy, and Future 

Development, which encompasses 

buildout of the remainder of the Lease 

Area and for which generation capacity 

has yet to be determined. Once 

operational, MarWin and Momentum 

Wind would advance the State of 

Maryland’s renewable energy goals of 50 

percent by the year 2030, with the full 

buildout of the Lease Area further 

achieving renewable energy targets. US 

Wind also anticipates completing the 

Future Development campaign within 

the effective period of the proposed 

rule. 

The Project would consist of several 

different types of permanent offshore 

infrastructure, including up to 114 

WTGs (e.g., 18–MW model with a 250- 

meter (m) rotor diameter platform), four 

OSSs, a Met tower, and inter-array and 

export cables. The Project is divided 

into three construction campaigns: 

MarWin, Momentum Wind, and Future 

Development (table 1). MarWin would 

occupy approximately 46.6 km2 (11,515 

acres) which would include 

approximately 21 WTGs and 1 OSS. The 

MarWin campaign, as well as 

subsequent Momentum Wind and 

Future Development, includes 

monopiles as the one potential WTG 

foundation type. For each campaign, the 

OSS would be supported by monopiles 

or jacket foundations with skirt piles. 

Skirt piles are post-piled pin piles. 

Jacket foundations are placed on the 

seabed and pin piles are driven into 

jacket pile guides, which are known as 

skirts. Table 1 provides a summary of 

each construction campaign. 

TABLE 1—US WIND’S ANTICIPATED CONSTRUCTION CAMPAIGN SCHEDULE

Campaigns Construction 

year 

Number of 11-m 

monopiles for 

WTGs 

Number 3-m pin piles 

for OSS jacket foundations 1

Number of 

1.8-m pin 

piles for 

Met tower 

Onshore export 

cables 

Offshore 

substations 

MarWin ................................................................. 1 (2025) 21 4 (1 jacket) ................... 0 4 1 

Momentum ........................................................... 2 (2026) 55 8 (2 jackets) .................. 3 0 2 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 507 

TABLE 1—US WIND’S ANTICIPATED CONSTRUCTION CAMPAIGN SCHEDULE—Continued 

Campaigns Construction 

year 

Number of 11-m 

monopiles for 

WTGs 

Number 3-m pin piles 

for OSS jacket foundations 1

Number of 

1.8-m pin 

piles for 

Met tower 

Onshore export 

cables 

Offshore 

substations 

Future Development ............................................. 3 (2027) 38 4 (1 jacket) ................... 0 0 1 

1Potential OSS foundations could also include monopile and suction bucket jacket foundations. 

Strings of WTGs will connect with the 

OSS via a submarine inter-array cable 

transmission system. Up to four highvoltage alternating current (HVAC) 

offshore export cables would be 

installed during the MarWin campaign, 

spanning approximately 65–97 km (40– 

60 miles (mi)) in length, dependent on 

the location of the OSS and the final 

routing. The Export Cable Corridor 

(ECC) would transmit electricity from 

the OSS to one or two landfall sites in 

Delaware Seashore State Park. 

The second construction campaign, 

Momentum Wind, would contain 

approximately 55 WTGs, 2 OSSs, and 1 

Met tower within an area of 

approximately 142.4 km2 (35,188 acres). 

The Met tower would be supported by 

pin pile foundations. During the third 

construction campaign, Future 

Development, approximately 38 WTGs 

and 1 OSS would be installed within an 

area of approximately 80.3 km2 (19,843 

acres). 

US Wind plans to install all monopile 

or pin pile foundations via impact pile 

driving. If suction bucket foundations 

are selected for OSS jacket foundations, 

impact pile driving would not be 

necessary. US Wind would also conduct 

the following supporting activities: 

temporary installation and subsequent 

removal of gravity cells to connect the 

offshore export cables to onshore 

facilities; permanently install scour 

protection around all foundations; 

permanently install and perform 

trenching, laying, and burial activities 

associated with the export cables from 

the OSSs to shore-based switching and 

sub-stations and WTG inter-array cables; 

and, during years 2 and 3, performance 

of HRG surveys using active acoustic 

sources with frequencies of less than 

180 kilohertz (kHz). Vessels would 

transit within the project area and 

anticipated between ports (Port Norris, 

NJ; Lewes, DE; Ocean City, MD; 

Baltimore, MD; Hampton Roads, VA; 

and Cape Charles, VA) and the Lease 

Area and cable corridors to transport 

crew, supplies, and materials to support 

construction activities. 

Up to four offshore export cables 

would be located among up to two 

corridors from the OSSs and connect to 

the planned landfall at either 3R’s Beach 

or Tower Road within Delaware 

Seashore State Park. When the cables 

reach the landfall site, they would be 

pulled into a cable duct generated by 

horizontal directional drilling (HDD), 

which would route the cables under the 

existing beach to subterranean transition 

vaults. All offshore cables would be 

connected to onshore export cables at 

the sea-to-shore transition point via 

trenchless installation (i.e., 

underground tunneling utilizing micro 

tunnel boring installation 

methodologies). 

Fishery monitoring surveys, 

performed via recreational boat-based 

surveys and a pot-based monitoring 

approach using ropeless gear 

technology, would be conducted in 

conjunction with the University of 

Maryland Center for Environmental 

Science (UMCES) to enhance existing 

data for specific benthic and pelagic 

species of concern. 

Dates and Duration 

As described above, US Wind would 

conduct 3 campaigns over 3 years: 

MarWin, Momentum Wind, and Future 

Development (table 1). In case of any 

delays to any campaign, NMFS is 

proposing a 5-year effective date of the 

proposed regulations and LOA; 

however, no more work in any given 

year or total over 5 years other than 

described here would occur. US Wind 

anticipates that activities with the 

potential to result in incidental take of 

marine mammals would occur 

throughout 3 of the 5 years (2025–2027) 

of the proposed regulations which, if 

issued, would be effective from January 

1, 2025 through December 31, 2029. 

Based on US Wind’s proposed schedule, 

the installation of all permanent 

structures would be completed by the 

end of November 2027. More 

specifically, US Wind would install 

piles only between May 1 and 

November 30. Also, the installation of 

WTG foundations and OSS 3-m pin pile 

jacket foundations is expected to occur 

during daylight hours between May 1 

and November 30 of 2025, 2026, and 

2027 (table 2); however, NMFS is 

proposing to allow nighttime pile 

driving if US Wind submits, and NMFS 

approves, an Alternative Monitoring 

Plan, as discussed below. The single 

Met tower foundation would be 

installed in 2026 (table 2). 

US Wind anticipates HRG surveys 

using sparkers and boomers to occur 

during 2026 and 2027. Up to 14 days of 

HRG survey activity are planned from 

April through June 2026 during the 

Momentum campaign. In addition, up to 

14 days of HRG survey activity are 

planned from April through June 2027 

during the Future Development 

campaign. No HRG surveys using 

equipment that has the potential to 

result in the harassment of marine 

mammals (e.g., sparkers or boomers) are 

planned for the MarWin campaign 

during year 1. 

TABLE 2—US WIND’S ANTICIPATED CONSTRUCTION AND OPERATIONS SCHEDULE DURING THE EFFECTIVE PERIOD OF THE

LOA 1

Project activity Construction campaign Expected timing 2 Expected duration 

(approximate) 

Scour Protection Pre-Installation ................. MarWin ................................ Year 1: Q2 through Q3 of 2025 ................. 21 days. 

Momentum Wind ................. Year 2: Q2 through Q3 of 2026 ................. 55 days. 

Future Development ............ Year 3: Q2 through Q3 of 2027 ................. 38 days. 

WTG Foundation Installation 3 5 ................... MarWin ................................ Year 1: June through September of 2025 .. 21 days. 

Momentum Wind ................. Year 2: May through August of 2026 ......... 55 days. 

Future Development ............ Year 3: June through August of 2027 ........ 38 days. 

Scour Protection Post-Installation ................ MarWin ................................ Year 1: Q2 through Q3 of 2025 ................. 42 days. 

Momentum Wind ................. Year 2: Q2 through Q3 of 2026 ................. 110 days. 

Future Development ............ Year 3: Q2 through Q3 of 2027 ................. 76 days. 

OSS Foundation Installation 3 5 .................... MarWin ................................ Year 1: July of 2025 ................................... 1 day. 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
508 Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 

TABLE 2—US WIND’S ANTICIPATED CONSTRUCTION AND OPERATIONS SCHEDULE DURING THE EFFECTIVE PERIOD OF THE

LOA 1—Continued 

Project activity Construction campaign Expected timing 2 Expected duration 

(approximate) 

Momentum Wind ................. Year 2: July of 2026 ................................... 2 days. 

Future Development ............ Year 3: July of 2027 ................................... 1 day. 

Met Tower Installation 3 4 ............................. Momentum Wind ................. Year 2: June of 2026 .................................. 1 day. 

HRG Surveys 5 ............................................. Momentum Wind ................. Year 2: Q2 through Q3 of 2026 ................. 14 days. 

Future Development ............ Year 3: Q2 through Q3 of 2027 ................. 14 days. 

Site Preparation ........................................... n/a ........................................ Not anticipated ............................................ n/a. 

Inter-array Cable Installation ........................ Marwin ................................. Year 1: Q2 through Q4 of 2025 ................. 42 days. 

Momentum Wind ................. Year 2: Q2 through Q4 of 2026 ................. 110 days. 

Future Development ............ Year 3: Q2 through Q4 of 2027 ................. 76 days. 

Export Cable Installation .............................. MarWin ................................ Year 1: Q1 through Q4 of 2025 ................. 60 days. 

Momentum Wind ................. Year 2: Q1 through Q4 of 2026 ................. 120 days (2 cables). 

Future Development ............ Year 3: Q1 through Q4 of 2027 ................. 60 days. 

Fishery Monitoring Surveys ......................... MarWin ................................ Q1 through Q4 Years 1–5 .......................... 16 days/year for commercial pot surveys. 

Momentum Wind .................

Future Development ............

12 days/year for recreational surveys. 

1While the effective period of the proposed regulations would extend through December 31, 2029, no activities are proposed to occur in 2028 or 2029 by US Wind 

so these were not included in this table. 2 Installation timing will depend on vessel availability, contractor selection, weather, and more. Year 1 is anticipated to be 2025, year 2 to be 2026, and year 3 to be 

2027, although these are subject to change per the factors identified. Note: ‘‘Q1, Q2, Q3, and Q4’’ each refer to a quarter of the year, starting in January and comprising 3 months each. Therefore, Q1 represents January through March, Q2 represents April through June, Q3 represents July through September, and Q4 represents October through December. 3The months identified here represent US Wind’s planned schedule; however, in case of unanticipated delays, foundation installation may occur between May 1 

and November 30 annually. 4 US Wind anticipates that all WTGs, OSS, and Met tower foundations will be installed by November 30, 2027; however, unanticipated delays may require some 

foundation pile driving to occur in years 4 (2028) or 5 (2029). 5 Represents HRG surveys that may result in take of marine mammals. US Wind plans to conduct HRG surveys that do not have the potential to result in take of 

marine mammals during Q2 through Q3 of year 1 given those surveys would utilize equipment all operating over 180kHz or have no acoustic output. 

Specific Geographic Region 

US Wind’s specified activities would 

occur within the Northeast U.S. 

Continental Shelf Large Marine 

Ecosystem (NES LME), an area of 

approximately 260,000 km2

(64,247,399.2 acres) from Cape Hatteras 

in the south to the Gulf of Maine in the 

north. Specifically, the specified 

geographic region is the Middle-Atlantic 

Bight (Mid-Atlantic Bight) sub-area of 

the NES LME. The Mid-Atlantic Bight 

encompasses waters of the Atlantic 

Ocean between Cape Hatteras, North 

Carolina and Martha’s Vineyard, 

Massachusetts, extending westward into 

the Atlantic to the 100-m isobath. In the 

Mid-Atlantic Bight, the pattern of 

sediment distribution is relatively 

simple. The continental shelf south of 

New England is broad and flat, 

dominated by fine grained sediments. 

Most of the surficial sediments on the 

continental shelf are sands and gravels. 

Silts and clays predominate at and 

beyond the shelf edge, with most of the 

slope being 70–100 percent mud. Fine 

sediments are also common in the shelf 

valleys leading to the submarine 

canyons. There are some larger 

materials, left by retreating glaciers, 

along the coast of Long Island and to the 

north and east. 

Primary productivity is highest in the 

nearshore and estuarine regions, with 

coastal phytoplankton blooms initiating 

in the winter and summer, although the 

timing and spatial extent of blooms 

varies from year to year. The relatively 

productive continental shelf supports a 

wide variety of fauna and flora, making 

it important habitat for various benthic 

and fish species and marine mammals, 

including but not limited to, fin whales, 

humpback whales, North Atlantic right 

whales, and other large whales as they 

migrate through the area. The Cold Pool, 

a bottom-trapped cold, nutrient-rich 

pool and distinct oceanographic feature 

of the Mid-Atlantic Bight, creates 

habitat that provides thermal refuge to 

cold water species in the area (Lentz, 

2017). Cold Pool waters, when upwelled 

to the surface, promote primary 

productivity within this region 

(Voynova et al., 2013). 

The seafloor in the Project Area is 

dynamic and changes over time due to 

current, tidal flows, and wave 

conditions. As the Lease Area is located 

just south of the mouth of Delaware Bay, 

the seafloor bedforms and sediments are 

affected by interactions between stormdriven currents, storm discharges from 

Delaware Bay, and tidal flows 

associated with Delaware Bay (US 

Wind, 2023b). The Lease Area is defined 

by medium-coarse grained sand at the 

surface and sub-surface interlays of clay 

and gravel (Alpine, 2015). The most 

prominent bathymetric features of the 

Lease Area are ridges and swales 

offshore of the Delmarva Peninsula that 

extend seaward from Delaware Bay (US 

Wind, 2023b). Sand ripples are present 

throughout the Project area. Sediment 

within the onshore export cable corridor 

is composed of predominantly silt-sand 

mixed with medium-coarse grained 

sand (US Wind, 2023b). The bottom 

habitat of Indian River Bay, through 

which the export cable route may pass 

through, is relatively flat in elevation 

and comprises fine to course-grained 

sands area. 

The benthic habitat of the Project 

Area contains a variety of seafloor 

substrates, physical features, and 

associated benthic organisms. The 

benthic macrofaunal community of the 

Lease Area is dominated by polychaetes 

and oligochaete worms yet may also 

include sand dollars, sea stars, tube 

anemones, hermit crabs, rock crabs, 

moon snails, nassa snails, surf clams, 

sea scallops, shrimp, and ocean quahog 

(Guida et al., 2017). 

Additional information on the 

underwater environment’s physical 

resources can be found in the COP for 

the Maryland Offshore Wind Project (US 

Wind, 2023b) available at: https://

www.boem.gov/renewable-energy/stateactivities/maryland-offshore-windconstruction-and-operations-plan. 

US Wind would construct the Project 

in Federal and State waters offshore of 

Maryland within the BOEM Lease Area 

OCS–A 0490 and associated export 

cable routes (figure 1). The Lease Area 

covers approximately 323.7 square 

kilometers (km2) (80,000 acres) and is 

located approximately 18.5 km offshore 

of Maryland. The water depths in the 

Lease Area range from 13 m along the 

western lease border to 41.5 m (43 to 

136.1 feet (ft)) along the southeast 

corner of the lease area while depths 

along the export cable routes range from 

10 m to 45 m (33 to 148 ft). Mean sea 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 509 

surface temperatures range from 42 to 

75.8 degrees Fahrenheit (°F; 5.56 to 24.3 

degrees Celsius (°C), while the depthaverage annual water temperature is 

58.2 °F (14.6 °C). Cables would come 

ashore at 3Rs Beach or Tower Road 

within Delaware Seashore State Park. 

The Project Area is defined as the Lease 

Area and export cable route area. 

BILLING CODE 3510–22–P 

BILLING CODE 3510–22–C 

Detailed Description of the Specified 

Activity 

Below, we provide detailed 

descriptions of US Wind’s planned 

activities, explicitly noting those that 

are anticipated to result in the take of 

marine mammals and for which 

incidental take authorization is 

requested. Additionally, a brief 

explanation is provided for those 

activities that are not expected to result 

in the take of marine mammals. 

WTG, OSS, and Met Tower Foundations 

US Wind proposes to install up to 114 

WTGs on monopile foundations, 4 OSSs 

on 3-m pin pile jacket foundations, and 

one Met tower on a 1.8-m pin pile 

foundation. US Wind is also considering 

monopile foundations and suction 

bucket jacket foundations for OSSs, 

although 3-m pin pile jacket 

foundations are the most likely 

foundation type. All WTG and OSS 

foundations would be installed between 

May 1 and November 30 in 2025 

(MarWin), 2026 (Momentum Wind), and 

2027 (Future Development) (refer back 

to table 1). No pile driving would occur 

December 1–April 30. For purposes of 

this proposed rule, US Wind assumed 

all foundations would be installed using 

an impact hammer, unless US Wind 


khammond on DSKJM1Z7X2PROD with PROPOSALS2EP04JA24.000</GPH>

Figure 1 -- The Maryland Offshore Wind Project Area 
510 Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 

uses gravity suction bucket-based jacket 

foundations for OSSs. 

A WTG monopile foundation 

typically consists of a coated single steel 

tubular section, with several sections of 

rolled steel plate welded together. Each 

monopile would have a maximum 

diameter of 11 m (36 ft). WTGs would 

be spaced approximately 0.77 nautical 

miles (nmi; 1.42 km) in an east-west 

direction and 1.02 nmi (1.89 km) in a 

north-south direction and driven to a 

maximum penetration depth of 50 m 

(164 ft) below the seafloor (US Wind, 

2023a). Monopile foundations would 

consist of a monopile with an integrated 

or separate transition piece. US Wind 

would install rock scour protection 

around the base of the monopile 

foundations prior to or following 

installation to minimize scour around 

the foundation bases (US Wind, 2023). 

Monopile foundations would be 

installed using an MHU 4400 impact 

hammer at a maximum hammer energy 

of 4,400 kJ. US Wind anticipates that 

one monopile will be installed per day 

at a rate of approximately 2 hours of 

active pile driving time per monopile, 

though two or more monopile 

installations per day may be possible 

depending on operational limitations 

and environmental conditions (table 3). 

Monopile, pin pile jacket, and gravity 

suction-bucket jacket foundations are 

technically and economically feasible 

for OSSs. Up to four OSSs would be 

installed via impact pile driving 

(monopile and pin pile jacket 

foundations) or dewatering process to 

sink suction buckets to the appropriate 

depth. Rock scour protection would be 

applied after foundation installation. 

Monopile foundations for the OSSs 

would have a maximum diameter of 11 

m (36 ft) and maximum pile penetration 

depth of 40 m (131 ft). Monopile 

foundations would have a separate 

transition piece with a number of Jtubes to support and protect cables as 

well as to connect the inter-array cables 

and the offshore export cable to the 

OSS. If monopiles are selected for the 

OSSs, monopiles would be installed 

through impact pile driving according to 

the same methods as described for WTG 

monopile foundations. 

Jacket foundations with pin piles, if 

selected for OSS design, may be prepiled or post-piled using pin piles with 

a maximum diameter of 3-m (9.8 ft). A 

pre-piled jacket would involve pin piles 

pre-installed in the seabed using a 

template. A post-piled jacket foundation 

is formed by a steel lattice construction 

(comprising tubular steel members and 

welded joints) secured to the seabed by 

means of hollow steel pin piles attached 

to the jacket where the pin piles have 

been driven through jacket skirts (skirt 

piles). Each jacket structure may have 

three, four, or six legs. A four-leg OSS 

with a post-piled pin pile jacket 

foundation is the most likely design and 

was selected for modeling impacts to 

marine mammals from OSS installation. 

Each jacket foundation would consist of 

up to four pin piles. In total, US Wind 

would install up to 4 OSSs for a total 

of 16 pin piles. Up to four 3-m pin piles 

would be installed per day using an 

impact hammer with a maximum 

hammer energy 1,500 kJ (table 3). Pin 

piles would have a maximum diameter 

of 3 m (9.8 ft) each and would be 

installed vertically. 

US Wind plans to install one Met 

tower to serve as a permanent metocean 

monitoring station. The Met tower 

foundation would be a Braced Caisson 

design, in which one main steel pile 

would be supported laterally by two 

steel supporting (bracing) piles. The 

main steel pin pile would have a 

maximum diameter of 1.8 m (72 in) and 

the two bracing pin piles would have a 

maximum diameter of 1.5 m (60 in). US 

Wind assumed bracing pin piles would 

be 1.8 m in diameter for the purposes 

of modeling impacts of installation on 

marine mammals. The main caisson and 

bracing piles would be installed using 

an impact hammer with a maximum 

energy of 500 kJ at a rate of 

approximately 2 hours per pin over the 

course of 2 days (table 3). The Met tower 

would include measurement devices to 

record weather conditions, such as wind 

and waves, in the Project Area. US 

Wind identified three potential 

locations for placement of the Met tower 

along the southern edge of the Lease 

Area, as shown in figure 1–2 of the ITA 

application. 

If US Wind installs suction bucket 

jacket foundations, they would have a 

maximum diameter of 15 m (49 ft) and 

pile penetration depth of 15 m (49 ft). 

Suction bucket jacket foundations 

would be installed through a dewatering 

process which generates pressure that 

draws the buckets to the desired depth. 

The process to install a suction bucket 

foundation does not produce elevated 

noise levels that could harass marine 

mammals; therefore, no take from this 

activity is anticipated to occur or is 

proposed to be authorized. Installation 

is not expected to result in take of 

marine mammals. Suction bucket 

foundations are not further discussed. 

TABLE 3—IMPACT PILE DRIVING SCHEDULE

Pile type Project 

component 

Max 

hammer 

energy 

(kJ) 1

Number of 

hammer 

blows 

Piling time 

duration 

per pile 

(min) 

Piling time 

duration 

per day 

(min) 

Number 

piles/day 

11-m monopile ....................................................................... WTG ...................................... 1,100 600 120 120 1 

2,200 2,400 

3,300 2 1,800 

3-m pin pile jacket foundations ............................................. OSS ....................................... 1,500 19,200 120 480 4 

1.8-m Steel Bracing Caisson pile 3 ....................................... Met tower .............................. 500 2,988 120 360 1 

1.8-m Steel Bracing pile 3 ...................................................... 2 

1Assumes MHU 4400 hammer. 

2 US Wind has proposed a hammer strike energy progression for impact pile driving of monopiles, beginning at a hammer energy of 1,100 kJ to an energy of 3,300 

kJ, although the maximum hammer energy possible (4,400 kJ) was used and scaled in the modeling. 3A bracing caisson design has one main pile supported laterally by two bracing piles. The bracing caisson pile and bracing piles for the Met tower are pin piles. 

While pre-piling preparatory work 

and post-piling activities could be 

ongoing at one foundation position as 

pile driving is occurring at another 

position, no concurrent/simultaneous 

pile driving of foundations would occur 

(see Dates and Duration section). 

Installation of foundations is anticipated 

to result in the take of marine mammals 

due to noise generated during pile 

driving. Proposed mitigation, 

monitoring, and reporting measures for 

impact pile driving are described in 

detail later in this document (see 

Proposed Mitigation and Proposed 

Monitoring and Reporting). 

US Wind anticipates the 21 WTGs to 

be installed during the MarWin 

campaign would become operational by 

December 31, 2025. The 55 WTGs to be 

installed during the Momentum Wind 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 511 

campaign would become operational by 

December 31, 2026, and the 38 WTGs to 

be installed during the Future 

Development campaign would become 

operational by December 31, 2027 (table 

2). 

HRG Surveys 

US Wind plans on conducting HRG 

surveys to identify any seabed debris or 

unexploded ordnance (UXO), confirm 

previously surveyed site conditions 

prior to cable installation, meet BOEM 

or other agency requirements for 

additional surveys, and to refine or 

(microsite) locations of construction 

footprints, WTG and OSS foundations, 

and cables. US Wind has committed to 

not detonating any UXOs. US Wind 

would prepare an avoidance plan for 

working around UXOs and conduct 

micro-siting surveys to identify any 

UXOs in the area. Only the micro-siting 

surveys have the potential to result in 

harassment of marine mammals and 

would be limited to the Lease Area. Preconstruction and UXO HRG surveys 

would utilize equipment that have 

operating frequencies that are above 

relevant marine mammal hearing 

thresholds or no acoustic output (e.g., 

magnetometers). Take is not anticipated 

from the use of this equipment; 

therefore, pre-construction and UXO 

HRG surveys are not analyzed further. 

HRG micro-siting surveys would 

occur within the Lease Area, focusing 

on the inter-array cable layout, as well 

as along the offshore export cable 

corridors, if necessary. US Wind 

estimates approximately 14 days of HRG 

micro-siting survey effort per year from 

April through June during years 2 and 

3 (Momentum Wind in 2026, Future 

Development in 2027) and only during 

daylight hours. HRG micro-siting 

surveys would be conducted using one 

vessel at a time. Up to 111.1 km of 

survey lines would be surveyed per 

vessel each survey day at approximately 

7.4 km/hour (4 knots (kn)) during 

daylight hours. Acoustic equipment 

described above (multibeam 

echosounders, side scan sonars, and 

marine magnetometers) may be used 

during micro-siting surveys as well as 

non-impulsive ultra-short baseline 

positioning equipment (i.e., Ultra-Short 

BaseLine (USBL) and other parametric 

sub-bottom profilers), shallow 

penetration sub-bottom profilers (SBPs) 

(e.g., Innomar SES–2000 non-parametric 

SBP), and medium penetration SBPs 

(e.g., sparkers and boomers). Take is not 

anticipated resulting from the use of 

ultra-short baseline position equipment 

or the Innomar SBP as these equipment 

types have a very narrow beam width 

which limits acoustic propagation, and 

these sources are not analyzed further. 

Of the HRG equipment types 

proposed for use during micro-siting 

surveys, the following sources have the 

potential to result in take of marine 

mammals: 

• Medium penetration SBPs 

(boomers) to map deeper subsurface 

stratigraphy as needed. A boomer is a 

broad-band sound source operating in 

the 0.2 kHz to 15 kHz frequency range. 

This system is typically mounted on a 

sled and towed behind the vessel. 

• Medium penetration SBPs 

(sparkers) to map deeper subsurface 

stratigraphy as needed. A sparker 

creates acoustic pulses from 0.05 kHz to 

3 kHz omni-directionally from the 

source that can penetrate several 

hundred meters into the seafloor. These 

are typically towed behind the vessel 

with adjacent hydrophone arrays to 

receive the return signals. 

Table 4 provides a list of the 

equipment specifications for the 

medium penetration SBPs that may 

result in take of marine mammals 

during HRG micro-siting surveys. 

Equipment with operating frequencies 

above 180 kHz are not discussed further 

because they are outside the general 

hearing range of marine mammals and 

therefore do not have the potential to 

cause harassment. Although US Wind 

has proposed a beamwidth of 100 

degrees for the Geo Spark sparker, 

NMFS has determined that a 180-degree 

beamwidth is more appropriate for this 

analysis, as sparkers are considered 

omnidirectional sources (Ruppel et al., 

2022). Additionally, US Wind proposed 

an RMS source level of 219 decibels 

(dB), based on a manufacturer 

specification. Because it was not clear 

which operating energy, tip 

configuration, or specific sparker model 

this source level was based on, and also 

because the manufacturer-provided 

source levels are not well-documented, 

NMFS considers the well-documented 

measurements for a wide variety of 

sparker configurations from Crocker and 

Fratantonio (2016) to be the bestavailable data for use in deriving 

appropriate proxy source levels. 

Further, the RMS source levels are given 

directly in Crocker and Fratantonio 

(2016), thus mitigating uncertainty 

associated with deriving RMS levels 

from peak levels. For these reasons, we 

have instead used an RMS source level 

of 206 dB, based on Crocker and 

Fratantonio (2016) and a 3 dB 

adjustment to account for the potential 

use of two 400 tip decks. Source 

characteristics and details of the source 

proxy are found in Table 4, and its 

footnotes below. The net result of 

NMFS’s changes to the proposed 

methodology is an increase of the Level 

B isopleth from 50.1 m to 200 m. 

Proposed mitigation, monitoring, and 

reporting measures for HRG micro-siting 

surveys are described in detail later in 

this document (see Proposed Mitigation 

and Proposed Monitoring and 

Reporting). 

TABLE 4—SUMMARY OF REPRESENTATIVE HRG MICRO-SITING SURVEY EQUIPMENT THAT MAY RESULT IN TAKE OF

MARINE MAMMALS 1

HRG system Representative 

survey equipment 

Operating 

frequencies 

(kHz) 

Peak 

source 

level 

(dBpeak) 

RMS source 

level 

(dBRMS) 

Pulse 

duration 

(ms) 

Repetition 

rate 

(Hz) 

Beamwidth 

(degrees) 

Medium- penetration SBP ............. Applied Acoustic S Boomer 2 ........ 0.1–5 211 205 0.6 3 80 

AA Dura Spark 400 tip (500 J) 3 ... 0.3–4 214 206 2.3 2 180 

dB = decibels; Hz = hertz. 

1Of note, NMFS has performed a preliminary review of a report submitted by Rand (2023), that includes measurements of the Geo-Marine Geo-Source 400 sparker (400 tip, 800 J), and suggests that NMFS is assuming lower source and received levels than appropriate in its assessments of HRG impacts. NMFS has determined that the values in our assessment remain appropriate, based on the model methodology (i.e., source level propagated using spherical spreading) here predicting a peak level 3 dB louder than the maximum measured peak levels at the closest measurement range in Rand (2023). NMFS will continue reviewing any available data relevant to these sources. 2 Crocker and Fratantonio (2016) provide Applied Acoustics S Boomer measurements. Frequency and repetition rate of the Applied Acoustics S Boomer verified by 

survey contractors. 3AA Dura-Spark 400 tip used as a proxy due to similar configuration and energy to the Geo-spark 2000. See Table 10 in Crocker and Fratantonio (2016) source 

levels for 500 J setting and 400 tips. Based on previous survey experience, US Wind expects to operate the Geo-spark at 400–500 J per 400 tip deck, with the possibility of one or two total 400 tip decks (i.e., 400–1000 J total energy). To account for the potential of two decks, the source level is doubled in energy, which results in 

the addition of approximately 3 dB (to the 206 dB RMS, as shown in Table 4). 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
512 Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 

Cable Landfall Construction 

US Wind would bring up to four 

offshore export cables through Indian 

River Bay to shore to landing locations 

at 3Rs Beach or Tower Road within the 

Delaware Seashore State Park (figure 1). 

The US Wind export cable would be 

connected to the onshore transmission 

cable at the landfall locations using 

horizontal directional drilling (HDD) 

and a jet plow. Cables would be pulled 

into cable ducts that would route the 

cables under the beach to subterranean 

transition vaults, located in existing 

developed areas such as parking lots. 

US Wind evaluated cofferdams at the 

HDD locations and determined that the 

use of a gravity cell would be more 

appropriate for soil conditions as well 

as avoid the use of a vibratory hammer 

that would create additional underwater 

sound. The gravity cell would be 

lowered onto the seafloor and would not 

require the walls of the cell to be driven 

into the seabed (i.e., no pile driving 

would occur). The HDD drill rig would 

be set up onshore in an excavated area 

and the drill would advance to the 

offshore exit point. The offshore cable 

would be pulled in through the HDD 

ducts into the cable jointing/transition 

vault at the landfall location. The cable 

installation vessel would then begin 

laying the cable on the seabed as 

described in the Cable Laying and 

Installation section below. Given the 

work is not expected to produce noise 

levels that could result in harassment to 

marine mammals, HDD and gravity cell 

installation is not expected to result in 

the take of marine mammals. US Wind 

did not request, and NMFS is not 

proposing to authorize, take associated 

with cable landfall construction; 

therefore, this activity is not discussed 

further. 

Cable Laying and Installation 

Cable burial operations would occur 

both in the Lease Area and ECCs from 

the Lease Area to shore. The inter-array 

cables would connect the WTGs to any 

one of the OSSs. All WTGs would 

connect to an OSS in strings of 4–6 

WTGs via the inter-array cables. Cables 

within the ECCs would carry power 

from the OSSs to shore at the landfall 

location(s) within Delaware Seashore 

State Park. The offshore export cables 

would be buried in the seabed at a target 

depth of up to 1 m (3.3 ft) to 3 m (9.8 

ft), although the exact depth would not 

exceed 4 m (13.1 ft). Inter-array cable 

burial operations would be installed to 

a target depth of 1 m (3.3 ft) to 2 m (6.6 

ft), not to exceed 4 m (13.1 ft) in depth 

and would follow installation of the 

WTG and OSS foundations as the 

foundations must be in place to provide 

connection points. Offshore cable 

installation may occur concurrently 

with foundation installation. 

Cable laying, cable installation, and 

cable burial activities planned to occur 

during the construction of the Project 

would include the following methods: 

offshore export cable pull through the 

HDD duct, simultaneous lay and burial 

for cable installation through the use of 

a jet plow, and post-lay burial for cables, 

as needed. Offshore export cables would 

be pulled through the HDD duct, as 

described in the Cable Landfall 

Construction section above. The interarray cables would be installed from a 

dynamically positioned cable 

installation vessel. US Wind plans to 

use a jet plow to achieve the target interarray and offshore cable burial depth. If 

necessary, post-lay cable burial would 

be completed through the use of a cable 

installation support vessel and remotely 

operated vehicle (ROV) system (US 

Wind, Inc., 2023a). Areas with cable 

crossings or hard bottoms may require 

additional protection measures, such as 

mattresses, rock placement, or cable 

protection systems. In shallow areas of 

cable installation, dredging may be 

necessary to allow access by the cable 

lay barge. As the noise levels generated 

from cable laying and installation work 

are low, the potential for take of marine 

mammals to result is discountable. US 

Wind is not requesting, and NMFS is 

not proposing, to authorize take 

associated with cable laying activities. 

Therefore, cable laying activities are not 

analyzed further in this document. 

Site Preparation and Scour Protection 

Site preparation typically includes 

sand bedform leveling, boulder 

clearance, pre-lay grapnel runs, and a 

pre-lay survey to prepare the area for 

export cable installation. Route 

clearance activities would be conducted 

prior to offshore export cable 

installation. Project activities would 

include a pre-installation survey and 

grapnel run along the offshore export 

cable corridor to remove debris that 

could impact the cable lay and burial. 

US Wind does not expect preinstallation seabed preparation, such as 

leveling, pre-trenching, to be necessary. 

A pre-lay grapnel run would be 

conducted along the cable route to 

remove debris that could impact cable 

lay and burial. 

US Wind would also deposit rock 

around each foundation as scour 

protection. Prior to or following the 

installation of a monopile or jacket 

foundation for the OSS, a first layer of 

scour protection rocks will be deployed 

in a circle around the pile location to 

stabilize the seabed (US Wind, Inc., 

2023a). If suction bucket foundations 

are selected for OSSs, scour protection 

would be deployed after buckets reach 

target penetration depth. A 1–2 m (2–7 

ft) thick second layer of larger rocks 

would be placed for stabilization once 

the inter-array cables have been pulled 

into the monopile. Scour protection may 

also be applied as additional protection 

for cables after burial. 

NMFS does not expect scour 

protection placement or site preparation 

work, including pre-lay grapnel runs 

and pre-lay surveys, to generate noise 

levels that would cause take of marine 

mammals. Although not anticipated, 

any necessary dredging, bedform 

leveling, or boulder clearance would be 

extremely localized at any given time, 

and NMFS expects that any marine 

mammals would not be exposed at 

levels or durations likely to disrupt 

behavioral patterns (i.e., migrating, 

foraging, calving, etc.). Therefore, the 

potential for the take of marine 

mammals to result from these activities 

is so low as to be discountable. US 

Wind did not request, and NMFS is not 

proposing, to authorize any takes 

associated with site preparation and 

scour protection activities; therefore, 

they are not analyzed further in this 

document. 

Vessel Operation 

US Wind will utilize various types of 

vessels over the course of the 5-year 

proposed regulations for surveying, 

foundation installation, cable 

installation, WTG and OSS installation, 

and support activities. US Wind has 

identified several existing port facilities 

located in Maryland, Virginia, Delaware, 

and New Jersey to support offshore 

construction, assembly and fabrication, 

crew transfer and logistics, and other 

operational activities. In addition, some 

components, materials, and vessels 

could come from Canadian and 

European ports. A variety of vessels 

would be used throughout the 

construction activities. These range 

from crew transportation vessels, 

tugboats, jack-up vessels, cargo ships, 

and various support vessels (table 5). 

Details on the vessels, related work, 

operational speeds, and general trip 

behavior can be found in table 1–2 of 

the ITA application and table 4–1 in the 

COP volume 1. 

As part of various vessel-based 

construction activities, including cable 

laying and construction material 

delivery, dynamic positioning thrusters 

may be utilized to hold vessels in 

position or move slowly. Sound 

produced through use of dynamic 

positioning thrusters is similar to that 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 513 

produced by transiting vessels, and 

dynamic positioning thrusters are 

typically operated either in a similarly 

predictable manner or used for short 

durations around stationary activities. 

Fall pipe vessels may use dynamic 

positioning thrusters during the 

installation of scour protection up to 24 

hours per day. Jack-up cranes or floating 

cranes may use dynamic positioning 

thrusters for up to 4 hours per WTG or 

OSS installation. Heavy lift and general 

cargo vessels may use dynamic 

positioning thrusters for the delivery of 

Project components from the 

manufacturing location to the staging/ 

assembly port only while maneuvering 

in port. Multipurpose offshore supply 

vessels may also use dynamic 

positioning thrusters throughout the day 

during the pre-lay grapnel run boulder 

clearance and cable burial. Jack-up or 

accommodation vessels may use 

dynamic positioning thrusters while 

constructing housing for offshore works, 

yet only while maneuvering to the site, 

which would last approximately 2 hours 

per WTG or OSS. Dynamic positioning 

thrusters may also be used by vessels 

throughout the day for pre-installation, 

geophysical and geotechnical 

verification surveys, cable installation, 

placement of scour protection and 

concrete mattresses, seabed preparation 

and leveling, and commissioning 

activities. Sound produced by dynamic 

positioning thrusters would be preceded 

by, and associated with, sound from 

ongoing vessel noise and would be 

similar in nature; thus, any marine 

mammals in the vicinity of the activity 

would be aware of the vessel’s presence. 

Construction-related vessel activity, 

including the use of dynamic 

positioning thrusters, is not expected to 

result in take of marine mammals. US 

Wind did not request, and NMFS does 

not propose to authorize, any take 

associated with vessel activity. 

The total vessels expected for use 

during the Project are provided in table 

5; more details can be found in table 1– 

2 of the ITA application. Assuming the 

maximum design scenario, 

approximately 458 total vessel round 

trips are expected to occur during the 

MarWin construction campaign (2025), 

approximately 1,944 total vessel round 

trips are expected to occur during the 

Momentum Wind construction 

campaign (2026), and approximately 

1,587 total vessel round trips are 

expected to occur during the Future 

Development construction campaign 

(2027). Vessels would remain on site 

during construction activities each year 

to reduce the number of transits 

between the Project Area and ports. 

For operations and maintenance, US 

Wind anticipates that up to 10 vessels 

could be used, although not all vessels 

would operate at the same time or every 

year. A fall pipe vessel, jack-up vessel, 

and multi-role survey vessel only be 

used for non-routine maintenance 

activities (table 5). Crew transfer vessels 

would not be likely to operate on a daily 

basis year-round, however, to be 

conservative, US Wind assumed that 

these vessels would operate on a daily 

basis (table 5). 

TABLE 5—TYPE AND NUMBER OF VESSELS ANTICIPATED DURING CONSTRUCTION AND OPERATIONS

Project period Vessel types Max number 

of vessels 

Expected 

maximum 

annual 

number 

of trips 1

Foundation Installation ................................................. Transport, Installation, and Support ............................. 5 10 

Crew Transfer ............................................................... 1 26 

Environmental Monitoring and Mitigation ..................... 4 52 

WTG Installation ........................................................... Transport, Installation, and Support ............................. 4 26 

Crew Transfer Vessel ................................................... 0 0 

Inter-array Cable Installation ........................................ Transport, Installation, and Support ............................. 4 5 

Crew Transfer Vessel ................................................... 2 136 

OSS Installation ............................................................ Transport, Installation, and Support ............................. 9 16 

Crew Transfer Vessel ................................................... 0 0 

Offshore Export Cable Installation ............................... Transport, Installation, and Support ............................. 6 25 

Crew Transfer Vessel ................................................... 0 0 

Operations and Maintenance 2 ..................................... Fall Pipe Vessel ............................................................ 1 1 

Crew Transfer Vessel (refueling) 3 ............................... 1 20 

Jack-up Vessel ............................................................. 1 1 

Multi-role Survey Vessel 4 ............................................ 2 13 

Sportfisher Vessel ........................................................ 1 100 

Crew Transfer Vessel ................................................... 4 365 5

1Vessels and trips provided represent the maximum number of year 2 trips for each vessel category for each activity from US Wind’s OCS air 

permit application, appendix A. 2Potential operation and maintenance ports include Ocean City, MD; Baltimore, MD; and Portsmouth, VA. 

3Only for non-routine maintenance activities 

4One of these vessels would be for non-routine maintenance activities 

5Expected maximum annual number of trips per year for each of the four vessels. Fourth vessel may not be necessary. 

While a vessel strike could cause 

injury or mortality of a marine mammal, 

NMFS is proposing to require extensive 

vessel strike avoidance measures that 

would avoid vessel strikes from 

occurring (see Proposed Mitigation 

section). US Wind has not requested, 

and NMFS is not proposing to 

authorize, take from vessel strikes. 

Fisheries and Benthic Monitoring 

Fisheries and benthic monitoring 

surveys are being designed for the 

project in collaboration with UMCES. 

UMCES and US Wind would conduct 

pot surveys and recreational fishing 

surveys focusing on evaluating the 

extent that commercial and recreational 

fisheries would be impacted due to 

changes in black sea bass aggregation 

behaviors during and after Project 

construction activities. The program 

includes a trial baseline year to test 

deployments and collect baseline data 

in the Project Area as well as a data 

synthesis year before construction 

activities would begin. UMCES and US 

Wind would conduct additional passive 

acoustic monitoring research for marine 

mammals. 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
514 Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 

Pot surveys offshore Ocean City 

would be conducted monthly from 

March through November using ropeless 

fishing gear to collect data on black sea 

bass relative abundance in the vicinity 

of the proposed turbine areas. Catches 

and sizes of other fauna would be 

assessed as well. US Wind would set 

strings of 15 pots (six strings, up to 90 

pots total) from a commercial fishing 

vessel, each string with a 1-day duration 

set period. EdgeTech ropeless gear 

(EdgeTech, 2023) would allow sets 

(trawls) of 15 pots without any rope in 

the water column. Approximately 300– 

355 m (984–1,165 ft) of 7⁄16 inch (in) 

main-line rope would lie on the bottom 

during the survey. There would also be 

approximately 1.5 m of 7⁄16 in line that 

would form the bridle connecting each 

pot to the main line. Each string of pots 

would consist of 15 black sea bass pots, 

an EdgeTech pot, and an anchor. The 

EdgeTech pot would be the release pot 

attached at the end of each trawl. Each 

survey would consist of six strings 

deployed for a 1-day soak time (see 

diagram in Proposed Rule Comment 

Responses Memo, October 12, 2023). 

After the 1-day set period, UMCES and 

US Wind would retrieve the pot trawls 

by sending a release command from the 

on-site research vessel to activate an 

acoustic release on the release pot. 

Upon activation, the flotation with the 

attached rope would ascend to the water 

surface. UMCES and US Wind would 

recover the floatation connected to the 

release pot as well as the rest of the pots 

for that trawl. The pot survey would be 

conducted under a NMFS Scientific 

LOA for black sea bass collection 

research, of which a similar letter was 

received by UMCES from NMFS Greater 

Atlantic Regional Fisheries Office 

(GARFO) for the initial trial baseline 

year. 

UMCES and US Wind would operate 

the recreational fishing survey off a 

recreational charter vessel based in 

Ocean City to compare data on black sea 

bass and other fauna between two 

artificial reef/wreck sites and two 

turbine sites using a Before-AfterControl-Impact (BACI) study design. 

Angling techniques, such as drop 

bottom fishing and jigging, would be 

used to collect catch data on black sea 

bass and other fauna. Six monthly 

recreational surveys spanning a 2-day 

window each, would be conducted 

annually from May through October. 

Passive acoustic monitoring research 

would focus on using rockhopper 

recorders to determine occurrence and 

position of large whales and dolphins as 

well as F–POD (full waveform capture 

Pod) devices to detect tonal 

echolocation clicks of small cetaceans in 

the Lease Area. The goal of the research 

would be to distinguish changes in 

marine mammal behavior due to natural 

inter-annual variation versus behaviors 

influenced by wind facility operations. 

US Wind and UMCES would use a 

before-during-after gradient design 

involving 2 years of monitoring in each 

period before, during, and after Project 

construction, from 2023 to 2029. The 

Rockhopper recorder would sample at 

200 kHz for baleen whales and dolphins 

while the F–POD would detect 

echolocation clicks of small cetaceans. 

Rockhopper recorders would include a 

localization array with the Lease Area to 

allow the positions of calling North 

Atlantic right whales, humpback 

whales, and dolphins to be detected. 

Innovasea receivers would also be 

attached at up to four mooring sites 

within the Lease Area to examine 

spatiotemporal patterns of previously 

tagged fish, such as Atlantic sturgeon, 

white sharks, and sand tiger sharks. 

Given the gear used (ropeless pot and 

hook and line), the fishery surveys 

present little risk to marine mammals 

(although some hook and line 

entanglement has been documented in 

marine mammals). To further minimize 

this already low risk of interaction, US 

Wind has proposed, and NMFS has 

included in the proposed rule, 

mitigation and monitoring measures to 

avoid taking marine mammals, 

including, but not limited to, 

monitoring for marine mammals before 

and during fishing/survey activities, not 

deploying, pulling gear, or fishing in 

certain circumstances, limiting tow 

times, and fully repairing nets and lines. 

All vessel captains and crew would also 

abide by the vessel strike avoidance 

measures outlined in § 217.344(b) of this 

rule. A full description of mitigation 

measures can be found in the Proposed 

Mitigation section. 

With the implementation of these 

measures, US Wind does not anticipate, 

and NMFS is not proposing to 

authorize, take of marine mammals 

incidental to research pot and 

recreational surveys. Given no take is 

anticipated from these surveys, impacts 

from fishery surveys will not be 

discussed further in this document 

(with the exception of the description of 

measures in the Proposed Mitigation 

section). 

Description of Marine Mammals in the 

Geographic Area 

Thirty-eight marine mammal species 

under NMFS’ jurisdiction have 

geographic ranges within the western 

North Atlantic OCS (Hayes et al., 2023). 

However, for reasons described below, 

US Wind has requested, and NMFS 

proposes to authorize, take of only 19 

species (comprising 20 stocks) of marine 

mammals. Sections 3 and 4 of US 

Wind’s ITA application summarize 

available information regarding status 

and trends, distribution and habitat 

preferences, and behavior and life 

history of the potentially affected 

species. NMFS fully considered all of 

this information, and we refer the reader 

to these descriptions in the application 

instead of reprinting the information. 

Additional information regarding 

population trends and threats may be 

found in NMFS’ Stock Assessment 

Reports (SARs; https://

www.fisheries.noaa.gov/national/ 

marine-mammal-protection/draftmarine-mammal-stock-assessmentreports) and more general information 

about these species (e.g., physical and 

behavioral descriptions) may be found 

on NMFS’ website (https://

www.fisheries.noaa.gov/find-species). 

Of the 38 marine mammal species 

and/or stocks with geographic ranges 

that include the Project Area (i.e., found 

in the coastal and offshore waters of 

Maryland), 19 species are not expected 

to be present or are considered rare or 

unexpected in the Project Area based on 

sighting and distribution data (see table 

3–1 in US Wind’s ITA application). 

Specifically, the following cetacean 

species are known to occur off of 

Maryland but are not expected to occur 

in the Project Area due to the location 

of preferred habitat outside the Lease 

Area and ECCs, based on the best 

available information, and therefore US 

Wind did not request, and NMFS is not 

proposing to authorize take, of these 

species: Blue whale (Balaenoptera 

musculus), Cuvier’s beaked whale 

(Ziphius cavirostris), four species of 

Mesoplodont beaked whales 

(Mesoplodon densitostris, M. europaeus, 

M. mirus, and M. bidens), Atlantic 

white-sided dolphin (Lagenorhynchus 

acutus), Clymene dolphin (Stenella 

clymene), dwarf sperm whale (Kogia 

sima), false killer whale (Pseudorca 

crassidens), Fraser’s dolphin 

(Lagenodelphis hosei), melon-headed 

whale (Peponocephala electra), 

northern bottlenose whale (Hyperoodon 

ampullatus), pygmy killer whale (Feresa 

attenuata), pygmy sperm whale (Kogia 

breviceps), sperm whale (Physeter 

macrocephalus), spinner dolphin 

(Stenella longirostris), and white-beaked 

dolphin (Lagenorhynchus albirostris). 

Two species of phocid pinnipeds are 

also uncommon in the Project Area, 

including: harp seals (Pagophilus 

groenlandica) and hooded seals 

(Cystophora cristata). However, harp 

seals are known to strand in coastal 

Maryland. Therefore, NMFS is 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 515 

proposing to authorize take of harp 

seals. 

In addition, the Florida manatee 

(Trichechus manatus, a sub-species of 

the West Indian manatee) has been 

previously documented as an occasional 

visitor to the Mid-Atlantic region during 

summer months (Morgan et al., 2002; 

Cummings et al., 2014). However, 

manatees are managed by the U.S. Fish 

and Wildlife Service (USFWS) and are 

not considered further in this document. 

Table 6 lists all species or stocks for 

which take is expected and proposed to 

be authorized for this action and 

summarizes information related to the 

population or stock, including 

regulatory status under the MMPA and 

Endangered Species Act (ESA) and 

potential biological removal (PBR), 

where known. PBR is defined as ‘‘the 

maximum number of animals, not 

including natural mortalities, that may 

be removed from a marine mammal 

stock while allowing that stock to reach 

or maintain its optimum sustainable 

population’’ (16 U.S.C. 1362(20)). While 

no mortality is anticipated or proposed 

to be authorized, PBR and annual 

serious injury and mortality from 

anthropogenic sources are included here 

as gross indicators of the status of the 

species or stocks and other threats. Take 

for 19 species (20 stocks) in table 6 is 

expected and proposed to be authorized 

for this activity. 

Marine mammal abundance estimates 

presented in this document represent 

the total number of individuals that 

make up a given stock, or the total 

number estimated within a particular 

study or survey area. NMFS’ stock 

abundance estimates for most species 

represent the total estimate of 

individuals within the geographic area, 

if known, that comprises that stock. For 

some species, this geographic area may 

extend beyond U.S. waters. All managed 

stocks in this region are assessed in 

NMFS’ U.S. Atlantic and Gulf of Mexico 

SARs. All values presented in table 6 

are the most recent available at the time 

of publication and, unless noted 

otherwise, use NMFS’ final 2022 SARs 

(Hayes et al., 2023) available online at 

https://www.fisheries.noaa.gov/ 

national/marine-mammal-protection/ 

draft-marine-mammal-stockassessment-reports. 

TABLE 6—MARINE MAMMAL SPECIES THAT MAY OCCUR IN THE PROJECT AREA AND BE TAKEN, BY HARASSMENT

Common name 1 Scientific name Stock 

ESA/ 

MMPA 

status; 

strategic 

(Y/N) 2

Stock abundance 

(CV, Nmin, most recent 

abundance survey) 3

PBR Annual 

M/SI 4

Order Artiodactyla—Cetacea—Mysticeti (baleen whales) 

Family Balaenidae: 

North Atlantic right whale ... Eubalaena glacialis ................... Western Atlantic ........................ E, D, Y 338 (0; 332; 2020); 356 

(346–363, 2022) 5.

0.7 6 31.2 

Family Balaenopteridae 

(rorquals): 

Fin whale ............................ Balaenoptera physalus ............. Western North Atlantic .............. E, D, Y 6,802 (0.24, 5573, 2016) 11 1.8 

Sei whale ............................ Balaenoptera borealis ............... Nova Scotia .............................. E, D, Y 6,292 (1.02, 3098, 2016) 6.2 0.8 

Minke whale ........................ Balaenoptera acutorostrata ...... Canadian Eastern Coastal ........ -, -, N 21,968 (0.31, 17,002, 

2016).

170 10.6 

Humpback whale ................ Megaptera novaeangliae .......... Gulf of Maine ............................ -, -, Y 1,396 (0, 1,380, 2016) .... 22 12.15 

Superfamily Odontoceti (toothed whales, dolphins, and porpoises) 

Family Delphinidae: 

Killer whale 7 ....................... Orcinus orca ............................. Western North Atlantic .............. -, -, N UNK (UNK, UNK, 2016) UNK 0 

Long-finned pilot whale ...... Globicephala melas .................. Western North Atlantic .............. -, -, N 39,215 (0.3, 30,627, 

2016).

306 29 

Short-finned pilot whale ...... Globicephala macrorhynchus ... Western North Atlantic .............. -, -, Y 28,924 (0.24, 23,637, 

2016).

236 136 

Bottlenose dolphin .............. Tursiops truncatus .................... Western North Atlantic Offshore -, -, N 62,851 (0.23, 51,914, 

2016).

519 28 

Bottlenose dolphin .............. Tursiops truncatus .................... Northern Migratory Coastal ...... -, -, Y 6,639 (0.41, 4,759, 2016) 48 12.2–21.5 

Common dolphin ................ Delphinus delphis ..................... Western North Atlantic .............. -, -, N 172,897 (0.21, 145,216, 

2016).

1,452 390 

Atlantic spotted dolphin ...... Stenella frontalis ....................... Western North Atlantic .............. -, -, N 39,921 (0.27, 32,032, 

2016).

320 0 

Pantropical spotted dolphin Stenella attenuata ..................... Western North Atlantic .............. -, D, N 6,593 (0.52, 4,367, 2016) 44 0 

Risso’s dolphin ................... Grampus griseus ...................... Western North Atlantic .............. -, -, N 35,215 (0.19, 30,051, 

2016).

301 34 

Rough-toothed dolphin 7 ..... Steno bredanensis .................... Western North Atlantic .............. -, -, N 136 (1, 67, 2016) ............ 0.7 0 

Striped dolphin 7 .................. Stenella coeruleoalba ............... Western North Atlantic .............. -, -, N 67,036 (0.29, 52,939, 

2016).

529 0 

Family Phocoenidae (porpoises): 

Harbor porpoise .................. Phocoena phocoena ................. Gulf of Maine/Bay of Fundy ...... -, -, N 95,543 (0.31, 74,034, 

2016).

851 164 

Order Carnivora—Pinnipedia 

Family Phocidae (earless seals): 

Harbor seal ......................... Phoca vitulina ........................... Western North Atlantic .............. -, -, N 61,336 (0.08, 57,637, 

2018).

1,729 339 

Gray seal 8 .......................... Halichoerus grypus ................... Western North Atlantic .............. -, -, N 27,300 (0.22, 22,785, 

2016).

1,389 4453 

Harp seal ............................ Pagophilus groenlandicus ......... Western North Atlantic .............. -, -, N 7.6M (UNK, 7.1M, 2019) 426,000 178,573 

1 Information on the classification of marine mammal species can be found on the web page for The Society for Marine Mammalogy’s Committee on Taxonomy 

(https://www.marinemammalscience.org/science-and-publications/list-marine-mammal-species-subspecies/; Committee on Taxonomy (2022)). 


khammond on DSKJM1Z7X2PROD with PROPOSALS2

I I I I 

I I I I 
516 Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 

2ESA status: Endangered (E), Threatened (T)/MMPA status: Depleted (D). A dash (-) indicates that the species is not listed under the ESA or designated as depleted under the MMPA. Under the MMPA, a strategic stock is one for which the level of direct human-caused mortality exceeds PBR, or which is determined to be 

declining and likely to be listed under the ESA within the foreseeable future. Any species or stock listed under the ESA is automatically designated under the MMPA 

as depleted and as a strategic stock. 3 NMFS 2022 marine mammal stock assessment reports online at: https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessments. CV is the coefficient of variation; Nmin is the minimum estimate of stock abundance. 4These values, found in NMFS’s SARs, represent annual levels of human-caused mortality plus serious injury from all sources combined (e.g., commercial fisheries, ship strike). 5The current SAR includes an estimated population (Nbest 338) based on sighting history through November 2020 (Hayes et al., 2023). In October 2023, NMFS released a technical report identifying that the North Atlantic right whale population size based on sighting history through 2022 was 356 whales, with a 95 percent 

credible interval ranging from 346 to 363 (Linden, 2023). 6Total annual average observed North Atlantic right whale mortality during the period 2016–2020 was 8.1 animals and annual average observed fishery mortality 

was 5.7 animals. Numbers presented in this table (31.2 total mortality and 22 fishery mortality) are 2015–2019 estimated annual means, accounting for undetected 

mortality and serious injury. 7 US Wind did not request take of these species; however, their exposure analysis demonstrates there is a low risk of harassment. Although these species are rare 

in the project area, NMFS is proposing to authorize a small amount of Level B harassment in the case of potential presence during pile driving. 8 NMFS’ stock abundance estimate (and associated PBR value) applies to the U.S. population only. Total stock abundance (including animals in Canada) is approximately 451,431. The annual M/SI value given is for the total stock. 

As indicated above, all 19 species and 

20 stocks in table 6 temporally and 

spatially co-occur with the activity to 

the degree that take is reasonably likely 

to occur. Three of the marine mammal 

species for which take is requested are 

listed as endangered under the ESA, 

including North Atlantic right, fin, and 

sei whales. In addition to what is 

included in sections 3 and 4 of US 

Wind’s ITA application (https://

www.fisheries.noaa.gov/action/ 

incidental-take-authorization-us-windinc-construction-and-operationmaryland-offshore-wind), the SARs 

(https://www.fisheries.noaa.gov/ 

national/marine-mammal-protection/ 

marine-mammal-stock-assessments), 

and NMFS’ website (https://

www.fisheries.noaa.gov/speciesdirectory/marine-mammals), we 

provide further detail below informing 

the baseline for select species (e.g., 

information regarding current UME and 

known important habitat areas, such as 

Biologically Important Areas (BIAs; 

https://oceannoise.noaa.gov/ 

biologically-important-areas) (Van 

Parijs, 2015)). There are no ESAdesignated critical habitats for any 

species within the project area (https:// 

www.fisheries.noaa.gov/resource/map/ 

national-esa-critical-habitat-mapper). 

Under the MMPA, a UME is defined 

as ‘‘a stranding that is unexpected; 

involves a significant die-off of any 

marine mammal population; and 

demands immediate response’’ (16 

U.S.C. 1421h(6)). As of July 2023, five 

UMEs are active. Four of these UMEs 

are occurring along the U.S. Atlantic 

coast for various marine mammal 

species. Of these, the most relevant to 

the project area are the North Atlantic 

right whale, humpback whale, and 

harbor and gray seal UMEs given the 

prevalence of these species in the 

project area. More information on 

UMEs, including all active, closed, or 

pending, can be found on NMFS’ 

website at https://

www.fisheries.noaa.gov/national/ 

marine-life-distress/active-and-closedunusual-mortality-events. 

Below, we include information for a 

subset of the species that presently have 

an active or recently closed UME 

occurring along the Atlantic coast or for 

which there is information available 

related to areas of biological 

significance. For the majority of species 

potentially present in the specific 

geographic region, NMFS has 

designated only a single generic stock 

(e.g., ‘‘western North Atlantic’’) for 

management purposes. This includes 

the ‘‘Canadian east coast’’ stock of 

minke whales, which includes all minke 

whales found in U.S. waters and is also 

a generic stock for management 

purposes. For humpback and sei 

whales, NMFS defines stocks on the 

basis of feeding locations (i.e., Gulf of 

Maine and Nova Scotia, respectively). 

However, references to humpback 

whales and sei whales in this document 

refer to any individuals of the species 

that are found in the project area. Any 

areas of known biological importance 

(including the BIAs identified in 

LaBrecque et al., 2015) that overlap 

spatially (or are adjacent) with the 

project area are addressed in the species 

sections below. 

North Atlantic Right Whale 

The North Atlantic right whale has 

been listed as Endangered since the 

ESA’s enactment in 1973. The species 

was recently uplisted from Endangered 

to Critically Endangered on the 

International Union for Conservation of 

Nature (IUCN) Red List of Threatened 

Species (Cooke, 2020). The uplisting 

was due to a decrease in population size 

(Pace et al., 2017), an increase in vessel 

strikes and entanglements in fixed 

fishing gear (Daoust et al., 2017; Davis 

& Brillant, 2019; Knowlton et al., 2012; 

Knowlton et al., 2022; Moore et al., 

2021; Sharp et al., 2019), and a decrease 

in birth rate (Pettis et al., 2022; Reed et 

al., 2022). The western Atlantic stock is 

considered depleted under the MMPA 

(Hayes et al., 2023). There is a recovery 

plan (NMFS, 2005) for the North 

Atlantic right whale, and NMFS 

completed 5-year reviews of the species 

in 2012, 2017, and 2022 which 

concluded no change to the listing 

status is warranted. 

Designated by NMFS as a Species in 

the Spotlight, the North Atlantic right 

whale is considered among the species 

with the greatest risk of extinction in the 

near future (https://

www.fisheries.noaa.gov/topic/ 

endangered-species-conservation/ 

species-in-the-spotlight). 

The North Atlantic right whale 

population had only a 2.8-percent 

recovery rate between 1990 and 2011 

and an overall abundance decline of 

23.5 percent from 2011 to 2019 (Hayes 

et al., 2023). Since 2011, the North 

Atlantic right whale population has 

been in decline; however, the sharp 

decrease observed from 2015 to 2020 

appears to have slowed, though the right 

whale population continues to 

experience annual mortalities above 

recovery thresholds (Pace et al., 2017; 

Pace et al., 2021; Linden, 2023). North 

Atlantic right whale calving rates 

dropped from 2017 to 2020 with zero 

births recorded during the 2017–2018 

season. The 2020–2021 calving season 

had the first substantial calving increase 

in 5 years with 20 calves born 

(including 2 mortalities) followed by 15 

calves during the 2021–2022 calving 

season and 12 births (including 1 

mortality) in 2022–2023 calving season. 

These data demonstrate that birth rates 

are increasing. However, mortalities 

continue to outpace births. Best 

estimates indicate fewer than 70 

reproductively active females remain in 

the population and adult females 

experience a lower average survival rate 

than males (Linden, 2023). In 2023, the 

total annual average observed North 

Atlantic right whale mortality increased 

from 8.1 (which represents 2016–2020) 

to 31.2 (which represents 2015–2019), 

however, this updated estimate also 

accounts for undetected mortality and 

serious injury (Hayes et al., 2023). 

Although the predicted number of 

deaths from the population are lower in 

recent years (2021–2022) when 

compared to the high number of deaths 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 517 

from 2014 to 2020 suggesting a shortterm increase in survival, annual 

mortality rates still exceed PBR (Linden, 

2023). 

Critical habitat for North Atlantic 

right whales is not present in the Project 

Area. However, the Project Area both 

spatially and temporally overlaps a 

portion of the migratory corridor BIA 

within which North Atlantic right 

whales migrate south to calving grounds 

generally in November and December, 

followed by a northward migration 

(primarily moms with young calves) 

into feeding areas far north of the 

Project Area in March and April 

(LaBrecque et al., 2015; Van Parijs, 

2015). North Atlantic right whale 

foraging may rarely opportunistically 

occur around the Project Area, yet the 

region is not considered primary 

foraging habitat. Engelhaupt et al. (2023) 

documented feeding and socializing 

behavior off Virginia and North 

Carolina, just south of the Project Area, 

suggesting that North Atlantic right 

whales may use the mid-Atlantic 

migratory corridor for more than just 

migration. 

NMFS’ regulations at 50 CFR 224.105 

designated Seasonal Management Areas 

(SMAs) for North Atlantic right whales 

in 2008 (73 FR 60173, October 10, 

2008). SMAs were developed to reduce 

the threat of collisions between ships 

and North Atlantic right whales around 

their migratory route and calving 

grounds. The Delaware Bay SMA 

overlaps with the export cable corridor 

of the proposed project. This SMA is 

currently active from November 1 

through April 30 of each year and may 

be used by North Atlantic right whales 

for migrating and/or feeding. As noted 

above, NMFS is proposing changes to 

the North Atlantic right whale speed 

rule (87 FR 46921, August 1, 2022). Due 

to the current status of North Atlantic 

right whales and the spatial proximity 

overlap of the proposed project with 

areas of biological significance, (i.e., a 

migratory corridor, SMA), the potential 

impacts of the proposed project on 

North Atlantic right whales warrant 

particular attention. 

During the spring, North Atlantic 

right whales use the migratory corridor 

BIA to move north from calving grounds 

off Georgia and Florida to feeding 

grounds in New England and Canadian 

waters (Hayes et al., 2023). Right whales 

feed primarily on the copepod, Calanus 

finmarchicus, a species whose 

availability and distribution has 

changed both spatially and temporally 

over the last decade due to an 

oceanographic regime shift that has 

been ultimately linked to climate 

change (Meyer-Gutbrod et al., 2021; 

Record et al., 2019; Sorochan et al., 

2019). This distribution change in prey 

availability has led to shifts in right 

whale habitat-use patterns over the 

same time period (Davis et al., 2020; 

Meyer-Gutbrod et al., 2022; QuintanoRizzo et al., 2021; O’Brien et al., 2022; 

Van Parijs et al., 2023) with reduced use 

of foraging habitats in the Great South 

Channel and Bay of Fundy and 

increased use of habitats within Cape 

Cod Bay and a region south of Martha’s 

Vineyard and Nantucket Islands (Stone 

et al., 2017; Mayo et al., 2018; Ganley 

et al., 2019; Record et al., 2019; MeyerGutbrod et al., 2021; Van Parijs et al., 

2023); these foraging habitats are all 

located several hundred kilometers 

north of the project area. In late fall (i.e., 

November), a portion of the right whale 

population (including pregnant females) 

typically departs the feeding grounds in 

the North Atlantic, moves south along 

the migratory corridor BIA, including 

through the Project Area, to right whale 

calving grounds off Georgia and Florida. 

Observations of these transitions in right 

whale habitat use, variability in 

seasonal presence in identified core 

habitats, and utilization of habitat 

outside of previously focused survey 

effort prompted the formation of a 

NMFS’ Expert Working Group, which 

identified current data collection efforts, 

data gaps, and provided 

recommendations for future survey and 

research efforts (Oleson et al., 2020). 

Recent research indicates understanding 

of their movement patterns remains 

incomplete and not all of the population 

undergoes a consistent annual migration 

(Davis et al., 2017; Gowan et al., 2019; 

Krzystan et al., 2018). Non-calving 

females may remain in the feeding 

grounds, during the winter in the years 

preceding and following the birth of a 

calf to increase their energy stores 

(Gowen et al., 2019). 

Although North Atlantic right whales 

move seasonally between foraging and 

calving grounds, Davis et al. (2017) 

acoustically detected right whales along 

the coast from Cape Hatteras, NC, 

United States to Nova Scotia, Canada 

year-round, suggesting that North 

Atlantic right whale use of the midAtlantic and southeast has increased 

since 2010 (Davis et al., 2017). North 

Atlantic right whale presence in the 

Project Area is predominately seasonal 

with individuals likely to be transient 

and migrating through the area. Bailey 

et al. (2018) acoustically detected the 

year-round presence of North Atlantic 

right whales in the vicinity of the 

Project Area, with a maximum 

abundance during the late winter and 

early spring. In addition, a monitoring 

buoy, deployed by UMCES offshore of 

Ocean City Maryland in 2022, 

acoustically detected the presence of 

North Atlantic right whales in the lease 

area from November through January, 

with the highest frequency of confirmed 

detections occurring during the months 

of December and January (Woods Hole 

Oceanographic Institute, 2022). Visual 

surveys also confirm a maximum 

abundance of North Atlantic right 

whales in the vicinity of the Lease Area 

during the winter (Barco et al., 2015; 

Williams et al., 2015). As part of the 

Mid-Atlantic Baseline Studies Project 

and Maryland Project, Williams et al. 

(2015) conducted standardized aerial 

and boat-based surveys of the Delaware, 

Maryland, Virginia Wind Energy Areas 

(WEAs), and visually observed North 

Atlantic right whales in the lease area 

during the months of February and 

March. Based upon year-round aerial 

surveys conducted from 2013 to 2015, 

Barco et al. (2015) observed the largest 

numbers of North Atlantic right whales 

in the Maryland WEA during the month 

of January, suggesting that the area may 

be a destination for non-breeding 

individuals and pulses of North Atlantic 

right whales may travel through the 

region. Barco et al. (2015) also 

documented North Atlantic right whale 

open mouth behavior, which is 

consistent with, though not necessarily 

indicative of, feeding. As part of the 

U.S. Navy’s Marine Species Monitoring 

Program, HDR has conducted aerial and 

vessel-based surveys for large whales off 

Virginia and North Carolina since 2015. 

The majority of North Atlantic right 

whale sightings have occurred in these 

areas, just south of the Project Area, 

during the months of January–March 

(Aschettino et al., 2023). The highest 

density month for North Atlantic right 

whales in the vicinity of the lease area 

is February (0.00076 individuals/km 

(0.54 nmi grid square)) (Roberts et al., 

2023). 

Since 2017, 98 dead, seriously 

injured, or sublethally injured or ill 

North Atlantic right whales along the 

United States and Canadian coasts have 

been documented, necessitating a UME 

declaration and investigation. The 

leading category for the cause of death 

for this ongoing UME is ‘‘human 

interaction,’’ specifically from 

entanglements or vessel strikes. As of 

October 30, 2023, there have been 36 

confirmed mortalities (dead, stranded, 

or floaters) and 34 seriously injured 

free-swimming whales for a total of 70 

whales. Beginning on October 14, 2022, 

the UME also considers animals with 

sublethal injury or illness bringing the 

total number of whales in the UME to 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
518 Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 

115. Approximately 42 percent of the 

population is known to be in reduced 

health (Hamilton et al., 2021) likely 

contributing to smaller body sizes at 

maturation, making them more 

susceptible to threats and reducing 

fecundity (Moore et al., 2021; Reed et 

al., 2022; Stewart et al., 2022). More 

information about the North Atlantic 

right whale UME is available online at 

https://www.fisheries.noaa.gov/ 

national/marine-life-distress/2017-2023- 

north-atlantic-right-whale-unusualmortality-event. 

Humpback Whale 

Humpback whales were listed as 

endangered under the Endangered 

Species Conservation Act (ESCA) in 

June 1970. In 1973, the ESA replaced 

the ESCA, and humpbacks continued to 

be listed as endangered. On September 

8, 2016, NMFS divided the once single 

species into 14 distinct population 

segments (DPS), removed the specieslevel listing, and, in its place, listed four 

DPSs as endangered and one DPS as 

threatened (81 FR 62259, September 8, 

2016). The remaining nine DPSs were 

not listed. The West Indies DPS, which 

is not listed under the ESA, is the only 

DPS of humpback whales that is 

expected to occur in the Project Area. 

Bettridge et al. (2015) estimated the size 

of the West Indies DPS population at 

12,312 (95 percent confidence interval 

(CI) 8,688–15,954) whales in 2004–2005, 

which is consistent with previous 

population estimates of approximately 

10,000–11,000 whales (Stevick et al., 

2003; Smith et al., 1999) and the 

increasing trend for the West Indies DPS 

(Bettridge et al., 2015). 

The Project Area does not overlap 

with any BIAs or other important areas 

for the humpback whales. A humpback 

whale feeding BIA extends throughout 

the Gulf of Maine, Stellwagen Bank, and 

Great South Channel from May through 

December, annually (LaBrecque et al., 

2015). However, this BIA is located 

approximately 556.2 km (345.6 mi) 

north of the Project Area, and thus, 

would not be impacted by project 

activities. 

Humpback whale presence in the 

mid-Atlantic varies seasonally. 

Humpback whales are most typically 

observed in this region during the 

winter months (Williams et al., 2015d; 

Barco et al., 2015) and are known to be 

migratory off coastal Maryland, moving 

seasonally between northern feeding 

grounds in New England and southern 

calving grounds in the West Indies 

(Hayes et al., 2023). However, not all 

humpback whales migrate to the 

Caribbean during the winter as 

individuals are sighted in mid- to highlatitude areas during this season 

(Swingle et al., 1993; Davis et al., 2020). 

In addition to a migratory pathway, the 

mid-Atlantic region also represents a 

supplemental winter feeding ground for 

juveniles and mature whales (Barco et 

al., 2002). Records of humpback whales 

off the U.S. mid-Atlantic coast (New 

Jersey south to North Carolina) suggest 

that these waters are used as a winter 

feeding ground from December through 

March (Mallette et al., 2017; Barco et al., 

2002; LaBrecque et al., 2015) and 

represent important habitat for 

juveniles, in particular (Swingle et al., 

1993; Wiley et al., 1995). 

Acoustic monitoring in the vicinity of 

the lease area has detected the presence 

of humpback whales year-round, 

although detections exhibit similar 

seasonal trends as visual sightings. 

Humpback whale detections were 

lowest during the summer months (June 

through September), increased through 

the winter (January through March) and 

peaked in April (Bailey et al., 2018). 

Davis et al. (2020) also found detections 

of humpback whales off the midAtlantic (Virginia) to peak from January 

through May. Density modeling (Roberts 

et al., 2023) confirms April (0.00187 

individuals per 1 km (0.54 nmi) grid 

cell) as the month of the highest average 

density of humpback whales in the 

vicinity of the Project Area. 

Since January 2016, elevated 

humpback whale mortalities along the 

Atlantic coast from Maine to Florida led 

to the declaration of a UME. As of 

October 2, 2023, 209 humpback whales 

have stranded as part of this UME. 

Partial or full necropsy examinations 

have been conducted on approximately 

90 of the known cases. Of the whales 

examined, about 40 percent had 

evidence of human interaction, either 

ship strike or entanglement. While a 

portion of the whales have shown 

evidence of pre-mortem vessel strike, 

this finding is not consistent across all 

whales examined and more research is 

needed. As the humpback whale 

population has grown, they are seen 

more often in the mid-Atlantic. Since 

January 2023, 34 humpbacks have 

stranded along the east coast of the 

United States (1 of these stranded in 

Maryland). These whales may have been 

following their prey (small fish) which 

were reportedly close to shore this past 

winter. These prey also attract fish that 

are targeted by recreational and 

commercial fishermen, which increases 

the number of boats in these areas. More 

information is available at https://

www.fisheries.noaa.gov/national/ 

marine-life-distress/active-and-closedunusual-mortality-events. 

Fin Whale 

Fin whales frequently occur in the 

waters of the U.S. Atlantic Exclusive 

Economic Zone (EEZ), principally from 

Cape Hatteras, North Carolina 

northward and are distributed in both 

continental shelf and deep-water 

habitats (Hayes et al., 2023). Although 

fin whales are present north of the 35- 

degree latitude region in every season 

and are broadly distributed throughout 

the western North Atlantic for most of 

the year, densities vary seasonally 

(Edwards et al., 2015; Hayes et al., 

2023). Fin whales typically feed in the 

Gulf of Maine and the waters 

surrounding New England, but their 

mating and calving (and general 

wintering) areas are largely unknown 

(Hain et al., 1992; Hayes et al., 2023). 

Acoustic detections of fin whale singers 

augment and confirm these visual 

sighting conclusions for males. 

Recordings from Massachusetts Bay, 

New York Bight, and deep-ocean areas 

have detected some level of fin whale 

singing from September through June 

(Watkins et al., 1987; Clark and Gagnon, 

2002; Morano et al., 2012). These 

acoustic observations from both coastal 

and deep-ocean regions support the 

conclusion that male fin whales are 

broadly distributed throughout the 

western North Atlantic for most of the 

year (Hayes et al., 2022). 

Fin whale feeding BIAs occur offshore 

of Montauk Point, New York from 

March to October (2,933 km2) (Hain et 

al., 1992; LaBrecque et al., 2015) and 

year-round in the southern Gulf of 

Maine (18,015 km2). However, given the 

more southerly location of the Project 

Area (located approximately 364.8 km 

(226.7 mi) and 546.2 km (339.4 mi) 

away from these BIAs, respectively), 

there is no spatial overlap from with 

these BIAs. 

Fin whales were among the most 

frequently observed baleen whale 

species during the Maryland Wind 

Energy Area aerial surveys conducted 

for the Maryland Department of Natural 

Resources (MD DNR) by the Virginia 

Aquarium and Marine Science Center 

Foundation (Barco et al., 2015), and the 

most commonly detected baleen whale 

species during acoustic monitoring 

surveys from 2014 to 2017 in the 

Maryland WEA, although the majority 

of detections were offshore of the WEA 

(Bailey et al., 2018a). Fin whale 

abundance in the vicinity of the Project 

Area peaked during the winter and early 

spring (Williams et al., 2015d; Barco et 

al., 2015), with the lowest occurrence 

documented during summer and early 

fall (Bailey et al., 2018). Consistent with 

visual sightings and acoustic detections, 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 519 

the highest average density of fin whales 

in the vicinity of the proposed Project 

Area occurs in January (0.00214 

individuals per 1 km (0.54 nmi) grid 

cell) (Roberts et al., 2023). There is no 

active fin whale UME. 

Minke Whale 

Minke whales are common and 

widely distributed throughout the U.S. 

Atlantic EEZ (Cetacean and Turtle 

Assessment Program (CETAP), 1982; 

Hayes et al., 2022), although their 

distribution has a strong seasonal 

component. Individuals have often been 

detected acoustically in shelf waters 

from spring to fall and more often 

detected in deeper offshore waters from 

winter to spring (Risch et al., 2013). 

Minke whales are abundant in New 

England waters from May through 

September (Pittman et al., 2006; Waring 

et al., 2014), yet largely absent from 

these areas during the winter, suggesting 

the possible existence of a migratory 

corridor (LaBrecque et al., 2015). A 

migratory route for minke whales 

transiting between northern feeding 

grounds and southern breeding areas 

may exist to the east of the Project Area, 

as minke whales may track warmer 

waters along the continental shelf while 

migrating (Risch et al., 2014). Risch et 

al. (2014) suggests the presence of a 

minke whale breeding ground offshore 

of the southeastern US during the 

winter. 

There are two minke whale feeding 

BIAs identified in the southern and 

southwestern section of the Gulf of 

Maine, including Georges Bank, the 

Great South Channel, Cape Cod Bay and 

Massachusetts Bay, Stellwagen Bank, 

Cape Anne, and Jeffreys Ledge from 

March through November, annually 

(LaBrecque et al., 2015). However, these 

BIAs are approximately 512.1 km (318.2 

mi) and 668.8 km (415.6 mi) northwest 

of the Project Area, respectively, and 

would not be impacted by the proposed 

project activities. 

Overall, minke whale use of the 

Project Area is likely highest during fall, 

winter, and spring months based upon 

visual sightings and acoustic detections 

in the vicinity of the lease area during 

the months of November, January, 

February, and April (Bailey et al., 

2018a; Barco et al., 2015; Williams et 

al., 2015b). The highest average density 

of minke whales in the vicinity of the 

lease area is expected to occur in May 

(0.00750 individuals per 1 km (0.54 

nmi)). 

From 2017 through 2022, elevated 

minke whale mortalities detected along 

the Atlantic coast from Maine through 

South Carolina resulted in the 

declaration of a UME. As of October 2, 

2023, a total of 160 minke whale 

mortalities have occurred during this 

UME. Full or partial necropsy 

examinations were conducted on more 

than 60 percent of the whales. 

Preliminary findings in several of the 

whales have shown evidence of human 

interactions or infectious disease, but 

these findings are not consistent across 

all of the minke whales examined, so 

more research is needed. More 

information is available at https://

www.fisheries.noaa.gov/national/ 

marine-life-distress/2017-2022-minkewhale-unusual-mortality-event-alongatlantic-coast. 

Sei Whale 

The Nova Scotia stock of sei whales 

can be found in deeper waters of the 

continental shelf edge of the eastern 

United States and northeastward to 

south of Newfoundland (Mitchell, 1975; 

Hain et al., 1985; Hayes et al., 2022). 

During spring and summer, the stock is 

mainly concentrated in northern feeding 

areas, including the Scotian Shelf 

(Mitchell and Chapman, 1977), the Gulf 

of Maine, Georges Bank, the Northeast 

Channel, and south of Nantucket 

(CETAP, 1982; Kraus et al., 2016; 

Roberts et al., 2016; Palka et al., 2017; 

Cholewiak et al., 2018; Hayes et al., 

2022). Sei whales have been detected 

acoustically along the Atlantic 

Continental Shelf and Slope from south 

of Cape Hatteras, North Carolina to the 

Davis Strait, with acoustic occurrence 

increasing in the mid-Atlantic region 

since 2010 (Davis et al., 2020). Although 

their migratory movements are not well 

understood, sei whales are believed to 

migrate north in June and July to 

feeding areas and south in September 

and October to breeding areas (Mitchell, 

1975; CETAP, 1982; Davis et al., 2020). 

Sei whales generally occur offshore; 

however, individuals may also move 

into shallower, more inshore waters 

(Payne et al., 1990; Halpin et al., 2009; 

Hayes et al., 2022). 

A sei whale feeding BIA occurs in 

New England waters from May through 

November (LaBrecque et al., 2015). 

However, this BIA is located 

approximately 501.5 km (311.6 mi) 

north of the Project Area and not likely 

to be impacted by the Project activities. 

Sei whales were sighted infrequently 

during visual surveys (Williams et al., 

2015d) and acoustic monitoring (WHOI, 

2022; WHOI, 2023) of the Maryland 

WEA. The highest average density of sei 

whales in the vicinity of the lease area 

is expected to occur during the month 

of April (0.00061 individuals per 1 km 

(0.54 nmi) (Roberts et al., 2023). There 

is no active sei whale UME. 

Phocid Seals 

Since June 2022, elevated numbers of 

harbor seal and gray seal mortalities 

have occurred across the southern and 

central coast of Maine. This event has 

been declared a UME. Preliminary 

testing of samples has found some 

harbor and gray seals positive for highly 

pathogenic avian influenza. While the 

UME is not occurring in the Project 

Area, the populations affected by the 

UME are the same as those potentially 

affected by the project. Information on 

this UME is available online at https:// 

www.fisheries.noaa.gov/2022-2023- 

pinniped-unusual-mortality-eventalong-maine-coast. 

The above event was preceded by a 

different UME, occurring from 2018 to 

2020 (closure of the 2018–2020 UME is 

pending). Beginning in July 2018, 

elevated numbers of harbor seal and 

gray seal mortalities occurred across 

Maine, New Hampshire, and 

Massachusetts. Additionally, stranded 

seals have shown clinical signs as far 

south as Virginia, although not in 

elevated numbers, therefore the UME 

investigation encompassed all seal 

strandings from Maine to Virginia. A 

total of 3,152 reported strandings (of all 

species) occurred from July 1, 2018, 

through March 13, 2020. Full or partial 

necropsy examinations have been 

conducted on some of the seals and 

samples have been collected for testing. 

Based on tests conducted thus far, the 

main pathogen found in the seals is 

phocine distemper virus. NMFS is 

performing additional testing to identify 

any other factors that may be involved 

in this UME, which is pending closure. 

Information on this UME is available 

online at: https://

www.fisheries.noaa.gov/new-englandmid-atlantic/marine-life-distress/2018- 

2020-pinniped-unusual-mortality-eventalong. 

Marine Mammal Hearing 

Hearing is the most important sensory 

modality for marine mammals 

underwater, and exposure to 

anthropogenic sound can have 

deleterious effects. To appropriately 

assess the potential effects of exposure 

to sound, it is necessary to understand 

the frequency ranges marine mammals 

are able to hear. Not all marine mammal 

species have equal hearing capabilities 

(e.g., Richardson et al., 1995; Wartzok 

and Ketten, 1999; Au and Hastings, 

2008). To reflect this, Southall et al. 

(2007, 2019a) recommended that marine 

mammals be divided into hearing 

groups based on directly measured 

(behavioral or auditory evoked potential 

techniques) or estimated hearing ranges 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
520 Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 

(behavioral response data, anatomical 

modeling, etc.). Note that no direct 

measurements of hearing ability have 

been successfully completed for 

mysticetes (i.e., low-frequency 

cetaceans). Subsequently, NMFS (2018) 

described generalized hearing ranges for 

these marine mammal hearing groups. 

Generalized hearing ranges were chosen 

based on the approximately 65-decibel 

(dB) threshold from the normalized 

composite audiograms, with the 

exception for lower limits for lowfrequency cetaceans where the lower 

bound was deemed to be biologically 

implausible and the lower bound from 

Southall et al. (2007) retained. Marine 

mammal hearing groups and their 

associated hearing ranges are provided 

in table 7. 

TABLE 7—MARINE MAMMAL HEARING GROUPS

[NMFS, 2018] 

Hearing group Generalized hearing 

range * 

Low-frequency (LF) cetaceans (baleen whales) ........................................................................................................................ 7 Hz to 35 kHz. 

Mid-frequency (MF) cetaceans (dolphins, toothed whales, beaked whales, bottlenose whales) .............................................. 150 Hz to 160 kHz. 

High-frequency (HF) cetaceans (true porpoises, Kogia, river dolphins, Cephalorhynchid, Lagenorhynchus cruciger & L. 

australis).

275 Hz to 160 kHz. 

Phocid pinnipeds (PW) (underwater) (true seals) ...................................................................................................................... 50 Hz to 86 kHz. 

Otariid pinnipeds (OW) (underwater) (sea lions and fur seals) ................................................................................................. 60 Hz to 39 kHz. 

* Represents the generalized hearing range for the entire group as a composite (i.e., all species within the group), where individual species’ 

hearing ranges are typically not as broad. Generalized hearing range chosen based on ∼65-dB threshold from normalized composite audiogram, 

with the exception for lower limits for LF cetaceans (Southall et al., 2007) and PW pinniped (approximation). 

The pinniped functional hearing 

group was modified from Southall et al. 

(2007) on the basis of data indicating 

that phocid species have consistently 

demonstrated an extended frequency 

range of hearing compared to otariids, 

especially in the higher frequency range 

(Hemila ̈ et al., 2006; Kastelein et al., 

2009; Reichmuth and Holt, 2013). For 

more detail concerning these groups and 

associated frequency ranges, please see 

NMFS (2018) for a review of available 

information. 

NMFS notes that in 2019a, Southall et 

al. recommended new names for 

hearing groups that are widely 

recognized. However, this new hearing 

group classification does not change the 

weighting functions or acoustic 

thresholds (i.e., the weighting functions 

and thresholds in Southall et al. (2019a) 

are identical to NMFS 2018 Revised 

Technical Guidance). When NMFS 

updates our Technical Guidance, we 

will be adopting the updated Southall et 

al. (2019a) hearing group classification. 

Potential Effects of Specified Activities 

on Marine Mammals and Their Habitat 

This section includes a summary and 

discussion of the ways that components 

of the specified activity may impact 

marine mammals and their habitat. The 

Estimated Take of Marine Mammals 

section later in this document includes 

a quantitative analysis of the number of 

individuals that are expected to be taken 

by this activity. The Negligible Impact 

Analysis and Determination section 

considers the content of this section, the 

Estimated Take of Marine Mammals 

section, and the Proposed Mitigation 

section, to draw conclusions regarding 

the likely impacts of these activities on 

the reproductive success or survivorship 

of individuals and how those impacts 

on individuals are likely to impact 

marine mammal species or stocks. 

General background information on 

marine mammal hearing was provided 

previously (see the Description of 

Marine Mammals in the Geographic 

Area section). Here, the potential effects 

of sound on marine mammals are 

discussed. 

US Wind has requested, and NMFS 

proposes to authorize, the take of 

marine mammals incidental to the 

construction activities associated with 

the project area. In their application, US 

Wind presented their analyses of 

potential impacts to marine mammals 

from the acoustic sources. NMFS both 

carefully reviewed the information 

provided by US Wind, as well as 

independently reviewed applicable 

scientific research and literature and 

other information to evaluate the 

potential effects of the Project’s 

activities on marine mammals. 

The proposed activities would result 

in the construction and placement of up 

to 119 permanent foundations to 

support WTGs, OSSs, a Met tower, and 

seafloor mapping using HRG surveys. 

There are a variety of types and degrees 

of effects to marine mammals, prey 

species, and habitat that could occur as 

a result of the Project. Below we provide 

a brief description of the types of sound 

sources that would be generated by the 

project, the general impacts from these 

types of activities, and an analysis of the 

anticipated impacts on marine 

mammals from the project, with 

consideration of the proposed 

mitigation measures. 

Description of Sound Sources 

This section contains a brief technical 

background on sound, on the 

characteristics of certain sound types, 

and on metrics used in this proposal 

inasmuch as the information is relevant 

to the specified activity and to a 

discussion of the potential effects of the 

specified activity on marine mammals 

found later in this document. For 

general information on sound and its 

interaction with the marine 

environment, please see: Au and 

Hastings, 2008; Richardson et al., 1995; 

Urick, 1983; as well as the Discovery of 

Sound in the Sea (DOSITS) website at 

https://www.dosits.org. Sound is a 

vibration that travels as an acoustic 

wave through a medium such as a gas, 

liquid, or solid. Sound waves alternately 

compress and decompress the medium 

as the wave travels. These compressions 

and decompressions are detected as 

changes in pressure by aquatic life and 

man-made sound receptors such as 

hydrophones (underwater 

microphones). In water, sound waves 

radiate in a manner similar to ripples on 

the surface of a pond and may be either 

directed in a beam (narrow beam or 

directional sources) or sound beams 

may radiate in all directions 

(omnidirectional sources). 

Sound travels in water more 

efficiently than almost any other form of 

energy, making the use of acoustics 

ideal for the aquatic environment and 

its inhabitants. In seawater, sound 

travels at roughly 1,500 meters per 

second (m/s). In-air, sound waves travel 

much more slowly, at about 340 m/s. 

However, the speed of sound can vary 

by a small amount based on 

characteristics of the transmission 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 521 

medium, such as water temperature and 

salinity. Sound travels in water more 

efficiently than almost any other form of 

energy, making the use of acoustics 

ideal for the aquatic environment and 

its inhabitants. In seawater, sound 

travels at roughly 1,500 m/s. In-air, 

sound waves travel much more slowly, 

at about 340 m/s. However, the speed of 

sound can vary by a small amount based 

on characteristics of the transmission 

medium, such as water temperature and 

salinity. 

The basic components of a sound 

wave are frequency, wavelength, 

velocity, and amplitude. Frequency is 

the number of pressure waves that pass 

by a reference point per unit of time and 

is measured in hertz (Hz) or cycles per 

second. Wavelength is the distance 

between two peaks or corresponding 

points of a sound wave (length of one 

cycle). Higher frequency sounds have 

shorter wavelengths than lower 

frequency sounds, and typically 

attenuate (decrease) more rapidly, 

except in certain cases in shallower 

water. 

The intensity (or amplitude) of 

sounds is measured in dB, which are a 

relative unit of measurement that is 

used to express the ratio of one value of 

a power or field to another. Decibels are 

measured on a logarithmic scale, so a 

small change in dB corresponds to large 

changes in sound pressure. For 

example, a 10-dB increase is a ten-fold 

increase in acoustic power. A 20-dB 

increase is then a hundred-fold increase 

in power and a 30-dB increase is a 

thousand-fold increase in power. 

However, a ten-fold increase in acoustic 

power does not mean that the sound is 

perceived as being 10 times louder. 

Decibels are a relative unit comparing 

two pressures; therefore, a reference 

pressure must always be indicated. For 

underwater sound, this is 1 microPascal 

(mPa). For in-air sound, the reference 

pressure is 20 microPascal (mPa). The 

amplitude of a sound can be presented 

in various ways; however, NMFS 

typically considers three metrics. In this 

proposed rule, all decibel levels are 

referenced to (re) 1mPa. 

Sound exposure level (SEL) 

represents the total energy in a stated 

frequency band over a stated time 

interval or event and considers both 

amplitude and duration of exposure 

(represented as dB re 1 mPa2-s). SEL is 

a cumulative metric; it can be 

accumulated over a single pulse (for pile 

driving this is often referred to as singlestrike SEL; SELss) or calculated over 

periods containing multiple pulses 

(SELcum). Cumulative SEL represents the 

total energy accumulated by a receiver 

over a defined time window or during 

an event. The SEL metric is useful 

because it allows sound exposures of 

different durations to be related to one 

another in terms of total acoustic 

energy. The duration of a sound event 

and the number of pulses, however, 

should be specified as there is no 

accepted standard duration over which 

the summation of energy is measured. 

Root mean square (rms) is the 

quadratic mean sound pressure over the 

duration of an impulse. Root mean 

square is calculated by squaring all of 

the sound amplitudes, averaging the 

squares, and then taking the square root 

of the average (Urick, 1983). Root mean 

square accounts for both positive and 

negative values; squaring the pressures 

makes all values positive so that they 

may be accounted for in the summation 

of pressure levels (Hastings and Popper, 

2005). This measurement is often used 

in the context of discussing behavioral 

effects, in part because behavioral 

effects, which often result from auditory 

cues, may be better expressed through 

averaged units than by peak pressures. 

Peak sound pressure (also referred to 

as zero-to-peak sound pressure or 0-pk) 

is the maximum instantaneous sound 

pressure measurable in the water at a 

specified distance from the source and 

is represented in the same units as the 

rms sound pressure. Along with SEL, 

this metric is used in evaluating the 

potential for PTS (permanent threshold 

shift) and TTS (temporary threshold 

shift). 

Sounds can be either impulsive or 

non-impulsive. The distinction between 

these two sound types is important 

because they have differing potential to 

cause physical effects, particularly with 

regard to hearing (e.g., Ward, 1997 in 

Southall et al., 2007). Please see NMFS 

et al. (2018) and Southall et al. (2007, 

2019a) for an in-depth discussion of 

these concepts. Impulsive sound 

sources (e.g., airguns, explosions, 

gunshots, sonic booms, impact pile 

driving) produce signals that are brief 

(typically considered to be less than 1 

second), broadband, atonal transients 

(American National Standards Institute 

(ANSI), 1986; ANSI, 2005; Harris, 1998; 

National Institute for Occupational 

Safety and Health (NIOSH), 1998; 

International Organization for 

Standardization (ISO), 2003) and occur 

either as isolated events or repeated in 

some succession. Impulsive sounds are 

all characterized by a relatively rapid 

rise from ambient pressure to a maximal 

pressure value followed by a rapid 

decay period that may include a period 

of diminishing, oscillating maximal and 

minimal pressures, and generally have 

an increased capacity to induce physical 

injury as compared with sounds that 

lack these features. Impulsive sounds 

are typically intermittent in nature. 

Non-impulsive sounds can be tonal, 

narrowband, or broadband, brief, or 

prolonged, and may be either 

continuous or intermittent (ANSI, 1995; 

NIOSH, 1998). Some of these nonimpulsive sounds can be transient 

signals of short duration but without the 

essential properties of pulses (e.g., rapid 

rise time). Examples of non-impulsive 

sounds include those produced by 

vessels, aircraft, machinery operations 

such as drilling or dredging, vibratory 

pile driving, and active sonar systems. 

Sounds are also characterized by their 

temporal component. Continuous 

sounds are those whose sound pressure 

level remains above that of the ambient 

sound with negligibly small fluctuations 

in level (NIOSH, 1998; ANSI, 2005) 

while intermittent sounds are defined as 

sounds with interrupted levels of low or 

no sound (NIOSH, 1998). NMFS 

identifies Level B harassment thresholds 

based on if a sound is continuous or 

intermittent. 

Even in the absence of sound from the 

specified activity, the underwater 

environment is typically loud due to 

ambient sound, which is defined as 

environmental background sound levels 

lacking a single source or point 

(Richardson et al., 1995). The sound 

level of a region is defined by the total 

acoustical energy being generated by 

known and unknown sources. These 

sources may include physical (e.g., 

wind and waves, earthquakes, ice, 

atmospheric sound), biological (e.g., 

sounds produced by marine mammals, 

fish, and invertebrates), and 

anthropogenic (e.g., vessels, dredging, 

construction) sound. A number of 

sources contribute to ambient sound, 

including wind and waves, which are a 

main source of naturally occurring 

ambient sound for frequencies between 

200 Hz and 50 kHz (International 

Council for the Exploration of the Sea 

(ICES), 1995). In general, ambient sound 

levels tend to increase with increasing 

wind speed and wave height. 

Precipitation can become an important 

component of total sound at frequencies 

above 500 Hz and possibly down to 100 

Hz during quiet times. Marine mammals 

can contribute significantly to ambient 

sound levels as can some fish and 

snapping shrimp. The frequency band 

for biological contributions is from 

approximately 12 Hz to over 100 kHz. 

Sources of ambient sound related to 

human activity include transportation 

(surface vessels), dredging and 

construction, oil and gas drilling and 

production, geophysical surveys, sonar, 

and explosions. Vessel noise typically 

dominates the total ambient sound for 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
522 Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 

frequencies between 20 and 300 Hz. In 

general, the frequencies of 

anthropogenic sounds are below 1 kHz, 

and if higher frequency sound levels are 

created, they attenuate rapidly. 

The sum of the various natural and 

anthropogenic sound sources that 

comprise ambient sound at any given 

location and time depends not only on 

the source levels (as determined by 

current weather conditions and levels of 

biological and human activity) but also 

on the ability of sound to propagate 

through the environment. In turn, sound 

propagation is dependent on the 

spatially and temporally varying 

properties of the water column and sea 

floor and is frequency-dependent. As a 

result of the dependence on a large 

number of varying factors, ambient 

sound levels can be expected to vary 

widely over both coarse and fine spatial 

and temporal scales. Sound levels at a 

given frequency and location can vary 

by 10–20 dB from day to day 

(Richardson et al., 1995). The result is 

that, depending on the source type and 

its intensity, sound from the specified 

activity may be a negligible addition to 

the local environment or could form a 

distinctive signal that may affect marine 

mammals. Human-generated sound is a 

significant contributor to the acoustic 

environment in the project location. 

Potential Effects of Underwater Sound 

on Marine Mammals 

Anthropogenic sounds cover a broad 

range of frequencies and sound levels 

and can have a range of highly variable 

impacts on marine life from none or 

minor to potentially severe responses 

depending on received levels, duration 

of exposure, behavioral context, and 

various other factors. Broadly, 

underwater sound from active acoustic 

sources, such as those in the Project, can 

potentially result in one or more of the 

following: temporary or permanent 

hearing impairment, non-auditory 

physical or physiological effects, 

behavioral disturbance, stress, and 

masking (Richardson et al., 1995; 

Gordon et al., 2003; Nowacek et al., 

2007; Southall et al., 2007; Go ̈tz et al., 

2009). Non-auditory physiological 

effects or injuries that theoretically 

might occur in marine mammals 

exposed to high level underwater sound 

or as a secondary effect of extreme 

behavioral reactions (e.g., change in 

dive profile as a result of an avoidance 

reaction) caused by exposure to sound 

include neurological effects, bubble 

formation, resonance effects, and other 

types of organ or tissue damage (Cox et 

al., 2006; Southall et al., 2007; Zimmer 

and Tyack, 2007; Tal et al., 2015). 

In general, the degree of effect of an 

acoustic exposure is intrinsically related 

to the signal characteristics, received 

level, distance from the source, and 

duration of the sound exposure, in 

addition to the contextual factors of the 

receiver (e.g., behavioral state at time of 

exposure, age class, etc.). In general, 

sudden, high-level sounds can cause 

hearing loss as can longer exposures to 

lower-level sounds. Moreover, any 

temporary or permanent loss of hearing 

will occur almost exclusively for noise 

within an animal’s hearing range. We 

describe below the specific 

manifestations of acoustic effects that 

may occur based on the activities 

proposed by US Wind. Richardson et al. 

(1995) described zones of increasing 

intensity of effect that might be 

expected to occur in relation to distance 

from a source and assuming that the 

signal is within an animal’s hearing 

range. First (at the greatest distance) is 

the area within which the acoustic 

signal would be audible (potentially 

perceived) to the animal but not strong 

enough to elicit any overt behavioral or 

physiological response. The next zone 

(closer to the receiving animal) 

corresponds with the area where the 

signal is audible to the animal and of 

sufficient intensity to elicit behavioral 

or physiological responsiveness. The 

third is a zone within which, for signals 

of high intensity, the received level is 

sufficient to potentially cause 

discomfort or tissue damage to auditory 

or other systems. Overlaying these zones 

to a certain extent is the area within 

which masking (i.e., when a sound 

interferes with or masks the ability of an 

animal to detect a signal of interest that 

is above the absolute hearing threshold) 

may occur; the masking zone may be 

highly variable in size. 

Below, we provide additional detail 

regarding potential impacts on marine 

mammals and their habitat from noise 

in general, starting with hearing 

impairment, as well as from the specific 

activities US Wind plans to conduct, to 

the degree it is available (noting that 

there is limited information regarding 

the impacts of offshore wind 

construction on marine mammals). 

Hearing Threshold Shift 

Marine mammals exposed to highintensity sound or to lower-intensity 

sound for prolonged periods can 

experience hearing threshold shift (TS), 

which NMFS defines as a change, 

usually an increase, in the threshold of 

audibility at a specified frequency or 

portion of an individual’s hearing range 

above a previously established reference 

level expressed in decibels (NMFS, 

2018). Threshold shifts can be 

permanent, in which case there is an 

irreversible increase in the threshold of 

audibility at a specified frequency or 

portion of an individual’s hearing range 

or temporary, in which there is 

reversible increase in the threshold of 

audibility at a specified frequency or 

portion of an individual’s hearing range 

and the animal’s hearing threshold 

would fully recover over time (Southall 

et al., 2019a). Repeated sound exposure 

that leads to TTS could cause PTS. 

When PTS occurs, there can be 

physical damage to the sound receptors 

in the ear (i.e., tissue damage) whereas 

TTS represents primarily tissue fatigue 

and is reversible (Henderson et al., 

2008). In addition, other investigators 

have suggested that TTS is within the 

normal bounds of physiological 

variability and tolerance and does not 

represent physical injury (e.g., Ward, 

1997; Southall et al., 2019a). Therefore, 

NMFS does not consider TTS to 

constitute auditory injury. Relationships 

between TTS and PTS thresholds have 

not been studied in marine mammals, 

and there is no PTS data for cetaceans. 

However, such relationships are 

assumed to be similar to those in 

humans and other terrestrial mammals. 

Noise exposure can result in either a 

permanent shift in hearing thresholds 

from baseline (a 40-dB threshold shift 

approximates a PTS onset; e.g., Kryter et 

al., 1966; Miller, 1974; Henderson et al., 

2008) or a temporary, recoverable shift 

in hearing that returns to baseline (a 6- 

dB threshold shift approximates a TTS 

onset; e.g., Southall et al., 2019a). Based 

on data from terrestrial mammals, a 

precautionary assumption is that the 

PTS thresholds, expressed in the 

unweighted peak sound pressure level 

metric (PK), for impulsive sounds (such 

as impact pile driving pulses) are at 

least 6 dB higher than the TTS 

thresholds and the weighted PTS 

cumulative sound exposure level 

thresholds are 15 (impulsive sound) to 

20 (non-impulsive sounds) dB higher 

than TTS cumulative sound exposure 

level thresholds (Southall et al., 2019a). 

Given the higher level of sound or 

longer exposure duration necessary to 

cause PTS as compared with TTS, PTS 

is less likely to occur as a result of these 

activities; however, it is possible, and a 

small amount has been proposed for 

authorization for several species. 

TTS is the mildest form of hearing 

impairment that can occur during 

exposure to sound, with a TTS of 6 dB 

considered the minimum threshold shift 

clearly larger than any day-to-day or 

session-to-session variation in a 

subject’s normal hearing ability 

(Schlundt et al., 2000; Finneran et al., 

2000; Finneran et al., 2002). While 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 523 

experiencing TTS, the hearing threshold 

rises, and a sound must be at a higher 

level in order to be heard. In terrestrial 

and marine mammals, TTS can last from 

minutes or hours to days (in cases of 

strong TTS). In many cases, hearing 

sensitivity recovers rapidly after 

exposure to the sound ends. There is 

data on sound levels and durations 

necessary to elicit mild TTS for marine 

mammals, but recovery is complicated 

to predict and dependent on multiple 

factors. 

Marine mammal hearing plays a 

critical role in communication with 

conspecifics, and interpretation of 

environmental cues for purposes such 

as predator avoidance and prey capture. 

Depending on the degree (elevation of 

threshold in dB), duration (i.e., recovery 

time), and frequency range of TTS, and 

the context in which it is experienced, 

TTS can have effects on marine 

mammals ranging from discountable to 

serious depending on the degree of 

interference of marine mammals 

hearing. For example, a marine mammal 

may be able to readily compensate for 

a brief, relatively small amount of TTS 

in a non-critical frequency range that 

occurs during a time where ambient 

noise is lower and there are not as many 

competing sounds present. 

Alternatively, a larger amount and 

longer duration of TTS sustained during 

time when communication is critical 

(e.g., for successful mother/calf 

interactions, consistent detection of 

prey) could have more serious impacts. 

Currently, TTS data only exist for four 

species of cetaceans (bottlenose 

dolphin, beluga whale (Delphinapterus 

leucas), harbor porpoise, and Yangtze 

finless porpoise (Neophocaena 

asiaeorientalis)) and six species of 

pinnipeds (northern elephant seal 

(Mirounga angustirostris), harbor seal, 

ring seal, spotted seal, bearded seal, and 

California sea lion (Zalophus 

californianus)) that were exposed to a 

limited number of sound sources (i.e., 

mostly tones and octave-band noise 

with limited number of exposure to 

impulsive sources such as seismic 

airguns or impact pile driving) in 

laboratory settings (Southall et al., 

2019a). There is currently no data 

available on noise-induced hearing loss 

for mysticetes. For summaries of data on 

TTS or PTS in marine mammals or for 

further discussion of TTS or PTS onset 

thresholds, please see Southall et al. 

(2019a) and NMFS (2018). 

Recent studies with captive 

odontocete species (bottlenose dolphin, 

harbor porpoise, beluga, and false killer 

whale) have observed increases in 

hearing threshold levels when 

individuals received a warning sound 

prior to exposure to a relatively loud 

sound (Nachtigall and Supin, 2013; 

Nachtigall and Supin, 2015; Nachtigall 

et al., 2016a; Nachtigall et al., 2016b; 

Nachtigall et al., 2016c; Finneran, 2018; 

Nachtigall et al., 2018). These studies 

suggest that captive animals have a 

mechanism to reduce hearing sensitivity 

prior to impending loud sounds. 

Hearing change was observed to be 

frequency dependent and Finneran 

(2018) suggests hearing attenuation 

occurs within the cochlea or auditory 

nerve. Based on these observations on 

captive odontocetes, the authors suggest 

that wild animals may have a 

mechanism to self-mitigate the impacts 

of noise exposure by dampening their 

hearing during prolonged exposures of 

loud sound or if conditioned to 

anticipate intense sounds (Finneran, 

2018; Nachtigall et al., 2018). 

Behavioral Effects 

Exposure of marine mammals to 

sound sources can result in, but is not 

limited to, no response or any of the 

following observable responses: 

increased alertness; orientation or 

attraction to a sound source; vocal 

modifications; cessation of feeding; 

cessation of social interaction; alteration 

of movement or diving behavior; habitat 

abandonment (temporary or permanent); 

and in severe cases, panic, flight, 

stampede, or stranding, potentially 

resulting in death (Southall et al., 2007). 

A review of marine mammal responses 

to anthropogenic sound was first 

conducted by Richardson (1995). More 

recent reviews address studies 

conducted since 1995 and focused on 

observations where the received sound 

level of the exposed marine mammal(s) 

was known or could be estimated 

(Nowacek et al., 2007; DeRuiter et al., 

2013; Ellison et al., 2012; Gomez et al., 

2016). Gomez et al. (2016) conducted a 

review of the literature considering the 

contextual information of exposure in 

addition to received level and found 

that higher received levels were not 

always associated with more severe 

behavioral responses and vice versa. 

Southall et al. (2021) states that results 

demonstrate that some individuals of 

different species display clear yet varied 

responses, some of which have negative 

implications while others appear to 

tolerate high levels and that responses 

may not be fully predictable with 

simple acoustic exposure metrics (e.g., 

received sound level). Rather, the 

authors state that differences among 

species and individuals along with 

contextual aspects of exposure (e.g., 

behavioral state) appear to affect 

response probability. 

Behavioral responses to sound are 

highly variable and context-specific. 

Many different variables can influence 

an animal’s perception of and response 

to (nature and magnitude) an acoustic 

event. An animal’s prior experience 

with a sound or sound source affects 

whether it is less likely (habituation) or 

more likely (sensitization) to respond to 

certain sounds in the future (animals 

can also be innately predisposed to 

respond to certain sounds in certain 

ways) (Southall et al., 2019a). Related to 

the sound itself, the perceived nearness 

of the sound, bearing of the sound 

(approaching vs. retreating), the 

similarity of a sound to biologically 

relevant sounds in the animal’s 

environment (i.e., calls of predators, 

prey, or conspecifics), and familiarity of 

the sound may affect the way an animal 

responds to the sound (Southall et al., 

2007; DeRuiter et al., 2013). Individuals 

(of different age, gender, reproductive 

status, etc.) among most populations 

will have variable hearing capabilities, 

and differing behavioral sensitivities to 

sounds that will be affected by prior 

conditioning, experience, and current 

activities of those individuals. Often, 

specific acoustic features of the sound 

and contextual variables (i.e., proximity, 

duration, or recurrence of the sound or 

the current behavior that the marine 

mammal is engaged in or its prior 

experience), as well as entirely separate 

factors, such as the physical presence of 

a nearby vessel, may be more relevant 

to the animal’s response than the 

received level alone. 

Overall, the variability of responses to 

acoustic stimuli depends on the species 

receiving the sound, the sound source, 

and the social, behavioral, or 

environmental contexts of exposure 

(e.g., DeRuiter and Doukara, 2012). For 

example, Goldbogen et al. (2013a) 

demonstrated that individual behavioral 

state was critically important in 

determining response of blue whales to 

sonar, noting that some individuals 

engaged in deep (greater than 50 m) 

feeding behavior had greater dive 

responses than those in shallow feeding 

or non-feeding conditions. Some blue 

whales in the Goldbogen et al. (2013a) 

study that were engaged in shallow 

feeding behavior demonstrated no clear 

changes in diving or movement even 

when received levels were high (∼160 

dB re 1mPa (microPascal)) for exposures 

to 3–4 kHz sonar signals, while deep 

feeding and non-feeding whales showed 

a clear response at exposures at lower 

received levels of sonar and 

pseudorandom noise. Southall et al. 

(2011) found that blue whales had a 

different response to sonar exposure 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
524 Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 

depending on behavioral state, more 

pronounced when deep feeding/travel 

modes than when engaged in surface 

feeding. 

With respect to distance influencing 

disturbance, DeRuiter et al. (2013) 

examined behavioral responses of 

Cuvier’s beaked whales to midfrequency sonar and found that whales 

responded strongly at low received 

levels (89–127 dB re 1mPa) by ceasing 

normal fluking and echolocation, 

swimming rapidly away, and extending 

both dive duration and subsequent nonforaging intervals when the sound 

source was 3.4–9.5 km away. 

Importantly, this study also showed that 

whales exposed to a similar range of 

received levels (78–106 dB re 1mPa) 

from distant sonar exercises (118 km 

away) did not elicit such responses, 

suggesting that context may moderate 

reactions. Thus, distance from the 

source is an important variable in 

influencing the type and degree of 

behavioral response and this variable is 

independent of the effect of received 

levels (e.g., DeRuiter et al., 2013; 

Dunlop et al., 2017a; Dunlop et al., 

2017b; Falcone et al., 2017; Dunlop et 

al., 2018; Southall et al., 2019a). 

Ellison et al. (2012) outlined an 

approach to assessing the effects of 

sound on marine mammals that 

incorporates contextual-based factors. 

The authors recommend considering not 

just the received level of sound, but also 

the activity the animal is engaged in at 

the time the sound is received, the 

nature and novelty of the sound (i.e., is 

this a new sound from the animal’s 

perspective), and the distance between 

the sound source and the animal. They 

submit that this ‘‘exposure context,’’ as 

described, greatly influences the type of 

behavioral response exhibited by the 

animal. Forney et al. (2017) also point 

out that an apparent lack of response 

(e.g., no displacement or avoidance of a 

sound source) may not necessarily mean 

there is no cost to the individual or 

population, as some resources or 

habitats may be of such high value that 

animals may choose to stay, even when 

experiencing stress or hearing loss. 

Forney et al. (2017) recommend 

considering both the costs of remaining 

in an area of noise exposure such as 

TTS, PTS, or masking, which could lead 

to an increased risk of predation or 

other threats or a decreased capability to 

forage, and the costs of displacement, 

including potential increased risk of 

vessel strike, increased risks of 

predation or competition for resources, 

or decreased habitat suitable for 

foraging, resting, or socializing. This 

sort of contextual information is 

challenging to predict with accuracy for 

ongoing activities that occur over large 

spatial and temporal expanses. 

However, distance is one contextual 

factor for which data exist to 

quantitatively inform a take estimate, 

and the method for predicting Level B 

harassment in this rule does consider 

distance to the source. Other factors are 

often considered qualitatively in the 

analysis of the likely consequences of 

sound exposure where supporting 

information is available. 

Behavioral change, such as 

disturbance manifesting in lost foraging 

time, in response to anthropogenic 

activities is often assumed to indicate a 

biologically significant effect on a 

population of concern. However, 

individuals may be able to compensate 

for some types and degrees of shifts in 

behavior, preserving their health and 

thus their vital rates and population 

dynamics. For example, New et al. 

(2013) developed a model simulating 

the complex social, spatial, behavioral, 

and motivational interactions of coastal 

bottlenose dolphins in the Moray Firth, 

Scotland, to assess the biological 

significance of increased rate of 

behavioral disruptions caused by vessel 

traffic. Despite a modeled scenario in 

which vessel traffic increased from 70 to 

470 vessels a year (a six-fold increase in 

vessel traffic) in response to the 

construction of a proposed offshore 

renewables’ facility, the dolphins’ 

behavioral time budget, spatial 

distribution, motivations, and social 

structure remained unchanged. 

Similarly, two bottlenose dolphin 

populations in Australia were also 

modeled over 5 years against a number 

of disturbances (Reed et al., 2020) and 

results indicate that habitat/noise 

disturbance had little overall impact on 

population abundances in either 

location, even in the most extreme 

impact scenarios modeled. Friedlaender 

et al. (2016) provided the first 

integration of direct measures of prey 

distribution and density variables 

incorporated into across-individual 

analyses of behavior responses of blue 

whales to sonar and demonstrated a 

fivefold increase in the ability to 

quantify variability in blue whale diving 

behavior. These results illustrate that 

responses evaluated without such 

measurements for foraging animals may 

be misleading, which again illustrates 

the context-dependent nature of the 

probability of response. 

The following subsections provide 

examples of behavioral responses that 

give an idea of the variability in 

behavioral responses that would be 

expected given the differential 

sensitivities of marine mammal species 

to sound, contextual factors, and the 

wide range of potential acoustic sources 

to which a marine mammal may be 

exposed. Behavioral responses that 

could occur for a given sound exposure 

should be determined from the 

literature that is available for each 

species, or extrapolated from closely 

related species when no information 

exists, along with contextual factors. 

Avoidance and Displacement 

Avoidance is the displacement of an 

individual from an area or migration 

path as a result of the presence of a 

sound or other stressors and is one of 

the most obvious manifestations of 

disturbance in marine mammals 

(Richardson et al., 1995). For example, 

gray whales (Eschrichtius robustus) and 

humpback whales are known to change 

direction—deflecting from customary 

migratory paths—in order to avoid noise 

from airgun surveys (Malme et al., 1984; 

Dunlop et al., 2018). Avoidance is 

qualitatively different from the flight 

response but also differs in the 

magnitude of the response (i.e., directed 

movement, rate of travel, etc.). 

Avoidance may be short-term with 

animals returning to the area once the 

noise has ceased (e.g., Malme et al., 

1984; Bowles et al., 1994; Goold, 1996; 

Stone et al., 2000; Morton and 

Symonds, 2002; Gailey et al., 2007; 

Da ̈hne et al., 2013; Russel et al., 2016). 

Longer-term displacement is possible, 

however, which may lead to changes in 

abundance or distribution patterns of 

the affected species in the affected 

region if habituation to the presence of 

the sound does not occur (e.g., 

Blackwell et al., 2004; Bejder et al., 

2006; Teilmann et al., 2006; Forney et 

al., 2017). Avoidance of marine 

mammals during the construction of 

offshore wind facilities (specifically, 

impact pile driving) has been 

documented in the literature with some 

significant variation in the temporal and 

spatial degree of avoidance and with 

most studies focused on harbor 

porpoises as one of the most common 

marine mammals in European waters 

(e.g., Tougaard et al., 2009; Da ̈hne et al., 

2013; Thompson et al., 2013; Russell et 

al., 2016; Brandt et al., 2018). 

Available information on impacts to 

marine mammals from pile driving 

associated with offshore wind is limited 

to information on harbor porpoises and 

seals, as the vast majority of this 

research has occurred at European 

offshore wind projects where large 

whales and other odontocete species are 

uncommon. Harbor porpoises and 

harbor seals are considered to be 

behaviorally sensitive species (e.g., 

Southall et al., 2007) and the effects of 

wind farm construction in Europe on 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 525 

these species have been well 

documented. These species have 

received particular attention in 

European waters due to their abundance 

in the North Sea (Hammond et al., 2002; 

Nachtsheim et al., 2021). A summary of 

the literature on documented effects of 

wind farm construction on harbor 

porpoise and harbor seals is described 

below. 

Brandt et al. (2016) summarized the 

effects of the construction of eight 

offshore wind projects within the 

German North Sea (i.e., Alpha Ventus, 

BARD Offshore I, Borkum West II, 

DanTysk, Global Tech I, Meerwind Su ̈d/ 

Ost, Nordsee Ost, and Riffgat) between 

2009 and 2013 on harbor porpoises, 

combining passive acoustic monitoring 

(PAM) data from 2010 to 2013 and aerial 

surveys from 2009 to 2013 with data on 

noise levels associated with pile 

driving. Results of the analysis revealed 

significant declines in porpoise 

detections during pile driving when 

compared to 25–48 hours before pile 

driving began, with the magnitude of 

decline during pile driving clearly 

decreasing with increasing distances to 

the construction site. During the 

majority of projects, significant declines 

in detections (by at least 20 percent) 

were found within at least 5–10 km of 

the pile driving site, with declines at up 

to 20–30 km of the pile driving site 

documented in some cases. Similar 

results demonstrating the long-distance 

displacement of harbor porpoises (18– 

25 km) and harbor seals (up to 40 km) 

during impact pile driving have also 

been observed during the construction 

at multiple other European wind farms 

(Tougaard et al., 2009; Bailey et al., 

2010; Da ̈hne et al., 2013; Lucke et al., 

2012; Haelters et al., 2015). 

While harbor porpoises and seals tend 

to move several kilometers away from 

wind farm construction activities, the 

duration of displacement has been 

documented to be relatively temporary. 

In two studies at Horns Rev II using 

impact pile driving, harbor porpoise 

returned within 1 to 2 days following 

cessation of pile driving (Tougaard et 

al., 2009; Brandt et al., 2011). Similar 

recovery periods have been noted for 

harbor seals off England during the 

construction of four wind farms 

(Brasseur et al., 2012; Carroll et al., 

2010; Hamre et al., 2011; Hastie et al., 

2015; Russell et al., 2016). In some 

cases, an increase in harbor porpoise 

activity has been documented inside 

wind farm areas following construction 

(e.g., Lindeboom et al., 2011). Other 

studies have noted longer term impacts 

after impact pile driving. Near Dogger 

Bank in Germany, harbor porpoises 

continued to avoid the area for over 2 

years after construction began (Gilles et 

al., 2009). Approximately 10 years after 

construction of the Nysted wind farm, 

harbor porpoise abundance had not 

recovered to the original levels 

previously seen, although the 

echolocation activity was noted to have 

been increasing when compared to the 

previous monitoring period (Teilmann 

and Carstensen, 2012). However, 

overall, there are no indications for a 

population decline of harbor porpoises 

in European waters (e.g., Brandt et al., 

2016). Notably, where significant 

differences in displacement and return 

rates have been identified for these 

species, the occurrence of secondary 

project-specific influences such as use 

of mitigation measures (e.g., bubble 

curtains, acoustic deterrent devices 

(ADDs)), or the manner in which species 

use the habitat in the project area, are 

likely the driving factors of this 

variation. 

NMFS notes the aforementioned 

studies from Europe involve installing 

much smaller piles than US Wind 

proposes to install and, therefore, we 

anticipate noise levels from impact pile 

driving to be louder. For this reason, we 

anticipate that the greater distances of 

displacement observed in harbor 

porpoise and harbor seals documented 

in Europe are likely to occur off 

Maryland. However, we do not 

anticipate any greater severity of 

response due to harbor porpoise and 

harbor seal habitat use off Maryland or 

population-level consequences similar 

to European findings. In many cases, 

harbor porpoises and harbor seals are 

resident to the areas where European 

wind farms have been constructed. 

However, off Maryland, harbor 

porpoises are transient (with higher 

abundances in winter when foundation 

installation would not occur) and a very 

small percentage of the large harbor seal 

population are only seasonally present 

with no rookeries established. In 

summary, we anticipate that harbor 

porpoise and harbor seals will likely 

respond to pile driving by moving 

several kilometers away from the source 

but return to typical habitat use patterns 

when pile driving ceases. 

Some avoidance behavior of other 

marine mammal species has been 

documented to be dependent on 

distance from the source. As described 

above, DeRuiter et al. (2013) noted that 

distance from a sound source may 

moderate marine mammal reactions in 

their study of Cuvier’s beaked whales 

(an acoustically sensitive species), 

which showed the whales swimming 

rapidly and silently away when a sonar 

signal was 3.4–9.5 km away while 

showing no such reaction to the same 

signal when the signal was 118 km away 

even though the received levels were 

similar. Tyack et al. (1983) conducted 

playback studies of Surveillance Towed 

Array Sensor System (SURTASS) lowfrequency active (LFA) sonar in a gray 

whale migratory corridor off California. 

Similar to North Atlantic right whales, 

gray whales migrate close to shore 

(approximately +2 km) and are lowfrequency hearing specialists. The LFA 

sonar source was placed within the gray 

whale migratory corridor 

(approximately 2 km offshore) and 

offshore of most, but not all, migrating 

whales (approximately 4 km offshore). 

These locations influenced received 

levels and distance to the source. For 

the inshore playbacks, not 

unexpectedly, the louder the source 

level of the playback (i.e., the louder the 

received level), whale avoided the 

source at greater distances. Specifically, 

when the source level was 170 dB rms 

and 178 dB rms, whales avoided the 

inshore source at ranges of several 

hundred meters, similar to avoidance 

responses reported by Malme et al. 

(1983, 1984). Whales exposed to source 

levels of 185 dB rms demonstrated 

avoidance levels at ranges of +1 km. 

Responses to the offshore source 

broadcasting at source levels of 185 and 

200 dB, avoidance responses were 

greatly reduced. While there was 

observed deflection from course, in no 

case did a whale abandon its migratory 

behavior. 

The signal context of the noise 

exposure has been shown to play an 

important role in avoidance responses. 

In a 2007–2008 Bahamas study, 

playback sounds of a potential 

predator—a killer whale—resulted in a 

similar but more pronounced reaction in 

beaked whales (an acoustically sensitive 

species), which included longer interdive intervals and a sustained straightline departure of more than 20 km from 

the area (Boyd et al., 2008; Southall et 

al., 2009; Tyack et al., 2011). US Wind 

does not anticipate, and NMFS is not 

proposing to authorize take of beaked 

whales and, moreover, the sounds 

produced by US Wind do not have 

signal characteristics similar to 

predators. Therefore, we would not 

expect such extreme reactions to occur. 

Southall et al. (2011) found that blue 

whales had a different response to sonar 

exposure depending on behavioral state, 

more pronounced when deep feeding/ 

travel modes than when engaged in 

surface feeding. 

One potential consequence of 

behavioral avoidance is the altered 

energetic expenditure of marine 

mammals because energy is required to 

move and avoid surface vessels or the 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
526 Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 

sound field associated with active sonar 

(Frid and Dill, 2002). Most animals can 

avoid that energetic cost by swimming 

away at slow speeds or speeds that 

minimize the cost of transport (MiksisOlds, 2006), as has been demonstrated 

in Florida manatees (Miksis-Olds, 2006). 

Those energetic costs increase, however, 

when animals shift from a resting state, 

which is designed to conserve an 

animal’s energy, to an active state that 

consumes energy the animal would 

have conserved had it not been 

disturbed. Marine mammals that have 

been disturbed by anthropogenic noise 

and vessel approaches are commonly 

reported to shift from resting to active 

behavioral states, which would imply 

that they incur an energy cost. 

Forney et al. (2017) detailed the 

potential effects of noise on marine 

mammal populations with high site 

fidelity, including displacement and 

auditory masking, noting that a lack of 

observed response does not imply 

absence of fitness costs and that 

apparent tolerance of disturbance may 

have population-level impacts that are 

less obvious and difficult to document. 

Avoidance of overlap between 

disturbing noise and areas and/or times 

of particular importance for sensitive 

species may be critical to avoiding 

population-level impacts because 

(particularly for animals with high site 

fidelity) there may be a strong 

motivation to remain in the area despite 

negative impacts. Forney et al. (2017) 

stated that, for these animals, remaining 

in a disturbed area may reflect a lack of 

alternatives rather than a lack of effects. 

A flight response is a dramatic change 

in normal movement to a directed and 

rapid movement away from the 

perceived location of a sound source. 

The flight response differs from other 

avoidance responses in the intensity of 

the response (e.g., directed movement, 

rate of travel). Relatively little 

information on flight responses of 

marine mammals to anthropogenic 

signals exist, but observations of flight 

responses to the presence of predators 

have occurred (Connor and Heithaus, 

1996; Frid and Dill, 2002). The result of 

a flight response could range from brief, 

temporary exertion and displacement 

from the area where the signal provokes 

flight to, in extreme cases, beaked whale 

strandings (Cox et al., 2006; D’Amico et 

al., 2009). However, it should be noted 

that response to a perceived predator 

does not necessarily invoke flight (Ford 

and Reeves, 2008), and whether 

individuals are solitary or in groups 

may influence the response. Flight 

responses of marine mammals have 

been documented in response to mobile 

high intensity active sonar (e.g., Tyack 

et al., 2011; DeRuiter et al., 2013; 

Wensveen et al., 2019), and more severe 

responses have been documented when 

sources are moving towards an animal 

or when they are surprised by 

unpredictable exposures (Watkins, 

1986; Falcone et al., 2017). Generally 

speaking, however, marine mammals 

would be expected to be less likely to 

respond with a flight response to either 

stationery pile driving (which they can 

sense is stationery and predictable) or 

significantly lower-level HRG surveys, 

unless they are within the area 

ensonified above behavioral harassment 

thresholds at the moment the source is 

turned on (Watkins, 1986; Falcone et al., 

2017). 

Diving and Foraging 

Changes in dive behavior in response 

to noise exposure can vary widely. They 

may consist of increased or decreased 

dive times and surface intervals as well 

as changes in the rates of ascent and 

descent during a dive (e.g., Frankel and 

Clark, 2000; Costa et al., 2003; Ng and 

Leung, 2003; Nowacek et al., 2004; 

Goldbogen et al., 2013a; Goldbogen et 

al., 2013b). Variations in dive behavior 

may reflect interruptions in biologically 

significant activities (e.g., foraging) or 

they may be of little biological 

significance. Variations in dive behavior 

may also expose an animal to 

potentially harmful conditions (e.g., 

increasing the chance of ship-strike) or 

may serve as an avoidance response that 

enhances survivorship. The impact of a 

variation in diving resulting from an 

acoustic exposure depends on what the 

animal is doing at the time of the 

exposure, the type and magnitude of the 

response, and the context within which 

the response occurs (e.g., the 

surrounding environmental and 

anthropogenic circumstances). 

Nowacek et al. (2004) reported 

disruptions of dive behaviors in foraging 

North Atlantic right whales when 

exposed to an alerting stimulus, an 

action, they noted, that could lead to an 

increased likelihood of ship strike. The 

alerting stimulus was in the form of an 

18-minute exposure that included three 

2-minute signals played three times 

sequentially. This stimulus was 

designed with the purpose of providing 

signals distinct to background noise that 

serve as localization cues. However, the 

whales did not respond to playbacks of 

either right whale social sounds or 

vessel noise, highlighting the 

importance of the sound characteristics 

in producing a behavioral reaction. 

Although source levels for the proposed 

pile driving activities may exceed the 

received level of the alerting stimulus 

described by Nowacek et al. (2004), 

proposed mitigation strategies (further 

described in the Proposed Mitigation 

section) will reduce the severity of 

response to proposed pile driving 

activities. Converse to the behavior of 

North Atlantic right whales, IndoPacific humpback dolphins have been 

observed to dive for longer periods of 

time in areas where vessels were present 

and/or approaching (Ng and Leung, 

2003). In both of these studies, the 

influence of the sound exposure cannot 

be decoupled from the physical 

presence of a surface vessel, thus 

complicating interpretations of the 

relative contribution of each stimulus to 

the response. Indeed, the presence of 

surface vessels, their approach, and 

speed of approach, seemed to be 

significant factors in the response of the 

Indo-Pacific humpback dolphins (Ng 

and Leung, 2003). Low-frequency 

signals of the Acoustic Thermometry of 

Ocean Climate (ATOC) sound source 

were not found to affect dive times of 

humpback whales in Hawaiian waters 

(Frankel and Clark, 2000) or to overtly 

affect elephant seal dives (Costa et al., 

2003). They did, however, produce 

subtle effects that varied in direction 

and degree among the individual seals, 

illustrating the equivocal nature of 

behavioral effects and consequent 

difficulty in defining and predicting 

them. 

Disruption of feeding behavior can be 

difficult to correlate with anthropogenic 

sound exposure, so it is usually inferred 

by observed displacement from known 

foraging areas, the cessation of 

secondary indicators of foraging (e.g., 

bubble nets or sediment plumes), or 

changes in dive behavior. As for other 

types of behavioral response, the 

frequency, duration, and temporal 

pattern of signal presentation, as well as 

differences in species sensitivity, are 

likely contributing factors to differences 

in response in any given circumstance 

(e.g., Croll et al., 2001; Nowacek et al., 

2004; Madsen et al., 2006; Yazvenko et 

al., 2007; Southall et al., 2019b). An 

understanding of the energetic 

requirements of the affected individuals 

and the relationship between prey 

availability, foraging effort and success, 

and the life history stage of the animal 

can facilitate the assessment of whether 

foraging disruptions are likely to incur 

fitness consequences (Goldbogen et al., 

2013b; Farmer et al., 2018; Pirotta et al., 

2018a; Southall et al., 2019a; Pirotta et 

al., 2021). 

Impacts on marine mammal foraging 

rates from noise exposure have been 

documented, though there is little data 

regarding the impacts of offshore 

turbine construction specifically. 

Several broader examples follow, and it 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 527 

is reasonable to expect that exposure to 

noise produced during the 5 years that 

the proposed rule would be effective 

could have similar impacts. Visual 

tracking, passive acoustic monitoring, 

and movement recording tags were used 

to quantify sperm whale behavior prior 

to, during, and following exposure to 

airgun arrays at received levels in the 

range 140–160 dB at distances of 7–13 

km, following a phase-in of sound 

intensity and full array exposures at 1– 

13 km (Madsen et al., 2006; Miller et al., 

2009). Sperm whales did not exhibit 

horizontal avoidance behavior at the 

surface. However, foraging behavior 

may have been affected. The sperm 

whales exhibited 19 percent less vocal 

(buzz) rate during full exposure relative 

to post exposure, and the whale that 

was approached most closely had an 

extended resting period and did not 

resume foraging until the airguns had 

ceased firing. The remaining whales 

continued to execute foraging dives 

throughout exposure; however, 

swimming movements during foraging 

dives were 6 percent lower during 

exposure than during control periods 

(Miller et al., 2009). Miller et al. (2009) 

noted that more data are required to 

understand whether the differences 

were due to exposure or natural 

variation in sperm whale behavior. 

Balaenopterid whales exposed to 

moderate low-frequency signals similar 

to the ATOC sound source 

demonstrated no variation in foraging 

activity (Croll et al., 2001), whereas five 

out of six North Atlantic right whales 

exposed to an acoustic alarm 

interrupted their foraging dives 

(Nowacek et al., 2004). Although the 

received SPLs were similar in the latter 

two studies, the frequency, duration, 

and temporal pattern of signal 

presentation were different. These 

factors, as well as differences in species 

sensitivity, are likely contributing 

factors to the differential response. The 

source levels of both the proposed 

construction and HRG activities exceed 

the source levels of the signals 

described by Nowacek et al. (2004) and 

Croll et al. (2001), and noise generated 

by US Wind’s activities at least partially 

overlap in frequency with the described 

signals. Blue whales exposed to midfrequency sonar in the Southern 

California Bight were less likely to 

produce low-frequency calls usually 

associated with feeding behavior 

(Melco ́n et al., 2012). However, Melco ́n 

et al. (2012) were unable to determine 

if suppression of low-frequency calls 

reflected a change in their feeding 

performance or abandonment of 

foraging behavior and indicated that 

implications of the documented 

responses are unknown. Further, it is 

not known whether the lower rates of 

calling actually indicated a reduction in 

feeding behavior or social contact since 

the study used data from remotely 

deployed, passive acoustic monitoring 

buoys. Results from the 2010–2011 field 

season of a behavioral response study in 

Southern California waters indicated 

that, in some cases and at low received 

levels, tagged blue whales responded to 

mid-frequency sonar but that those 

responses were mild and there was a 

quick return to their baseline activity 

(Southall et al., 2011; Southall et al., 

2012b; Southall et al., 2019). 

Information on or estimates of the 

energetic requirements of the 

individuals and the relationship 

between prey availability, foraging effort 

and success, and the life history stage of 

the animal will help better inform a 

determination of whether foraging 

disruptions incur fitness consequences. 

Foraging strategies may impact foraging 

efficiency, such as by reducing foraging 

effort and increasing success in prey 

detection and capture, in turn 

promoting fitness and allowing 

individuals to better compensate for 

foraging disruptions. Surface feeding 

blue whales did not show a change in 

behavior in response to mid-frequency 

simulated and real sonar sources with 

received levels between 90 and 179 dB 

re 1 mPa, but deep feeding and nonfeeding whales showed temporary 

reactions including cessation of feeding, 

reduced initiation of deep foraging 

dives, generalized avoidance responses, 

and changes to dive behavior (DeRuiter 

et al., 2017; Goldbogen et al., 2013b; 

Sivle et al., 2015). Goldbogen et al. 

(2013b) indicate that disruption of 

feeding and displacement could impact 

individual fitness and health. However, 

for this to be true, we would have to 

assume that an individual whale could 

not compensate for this lost feeding 

opportunity by either immediately 

feeding at another location, by feeding 

shortly after cessation of acoustic 

exposure, or by feeding at a later time. 

There is no indication that individual 

fitness and health would be impacted, 

particularly since unconsumed prey 

would likely still be available in the 

environment in most cases following the 

cessation of acoustic exposure. 

Similarly, while the rates of foraging 

lunges decrease in humpback whales 

due to sonar exposure, there was 

variability in the response across 

individuals, with one animal ceasing to 

forage completely and another animal 

starting to forage during the exposure 

(Sivle et al., 2016). In addition, almost 

half of the animals that demonstrated 

avoidance were foraging before the 

exposure, but the others were not; the 

animals that avoided while not feeding 

responded at a slightly lower received 

level and greater distance than those 

that were feeding (Wensveen et al., 

2017). These findings indicate the 

behavioral state of the animal and 

foraging strategies play a role in the type 

and severity of a behavioral response. 

For example, when the prey field was 

mapped and used as a covariate in 

examining how behavioral state of blue 

whales is influenced by mid-frequency 

sound, the response in blue whale deepfeeding behavior was even more 

apparent, reinforcing the need for 

contextual variables to be included 

when assessing behavioral responses 

(Friedlaender et al., 2016). 

Vocalizations and Auditory Masking 

Marine mammals vocalize for 

different purposes and across multiple 

modes, such as whistling, production of 

echolocation clicks, calling, and singing. 

Changes in vocalization behavior in 

response to anthropogenic noise can 

occur for any of these modes and may 

result directly from increased vigilance 

or a startle response, or from a need to 

compete with an increase in background 

noise (see Erbe et al., 2016 review on 

communication masking), the latter of 

which is described more below. 

For example, in the presence of 

potentially masking signals, humpback 

whales and killer whales have been 

observed to increase the length of their 

songs (Miller et al., 2000; Fristrup et al., 

2003; Foote et al., 2004) and blue 

whales increased song production (Di 

Iorio and Clark, 2009), while North 

Atlantic right whales have been 

observed to shift the frequency content 

of their calls upward while reducing the 

rate of calling in areas of increased 

anthropogenic noise (Parks et al., 2007). 

In some cases, animals may cease or 

reduce sound production during 

production of aversive signals (Bowles 

et al., 1994; Thode et al., 2020; Cerchio 

et al., 2014; McDonald et al., 1995). 

Blackwell et al. (2015) showed that 

whales increased calling rates as soon as 

airgun signals were detectable before 

ultimately decreasing calling rates at 

higher received levels. 

Sound can disrupt behavior through 

masking, or interfering with, an animal’s 

ability to detect, recognize, or 

discriminate between acoustic signals of 

interest (e.g., those used for intraspecific 

communication and social interactions, 

prey detection, predator avoidance, or 

navigation) (Richardson et al., 1995; 

Erbe and Farmer, 2000; Tyack, 2000; 

Erbe et al., 2016). Masking occurs when 

the receipt of a sound is interfered with 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
528 Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 

by another coincident sound at similar 

frequencies and at similar or higher 

intensity and may occur whether the 

sound is natural (e.g., snapping shrimp, 

wind, waves, precipitation) or 

anthropogenic (e.g., shipping, sonar, 

seismic exploration) in origin. The 

ability of a noise source to mask 

biologically important sounds depends 

on the characteristics of both the noise 

source and the signal of interest (e.g., 

signal-to-noise ratio, temporal 

variability, direction), in relation to each 

other and to an animal’s hearing 

abilities (e.g., sensitivity, frequency 

range, critical ratios, frequency 

discrimination, directional 

discrimination, age, or TTS hearing 

loss), and existing ambient noise and 

propagation conditions. 

Masking these acoustic signals can 

disturb the behavior of individual 

animals, groups of animals, or entire 

populations. Masking can lead to 

behavioral changes including vocal 

changes (e.g., Lombard effect, increasing 

amplitude, or changing frequency), 

cessation of foraging or lost foraging 

opportunities, and leaving an area, to 

both signalers and receivers, in an 

attempt to compensate for noise levels 

(Erbe et al., 2016) or because sounds 

that would typically have triggered a 

behavior were not detected. In humans, 

significant masking of tonal signals 

occurs as a result of exposure to noise 

in a narrow band of similar frequencies. 

As the sound level increases, the 

detection of frequencies above those of 

the masking stimulus decreases. This 

principle is expected to apply to marine 

mammals as well because of common 

biomechanical cochlear properties 

across taxa. 

Therefore, when the coincident 

(masking) sound is man-made, it may be 

considered harassment when disrupting 

behavioral patterns. It is important to 

distinguish TTS and PTS, which persist 

after the sound exposure, from masking, 

which only occurs during the sound 

exposure. Because masking (without 

resulting in threshold shift) is not 

associated with abnormal physiological 

function, it is not considered a 

physiological effect, but rather a 

potential behavioral effect. 

The frequency range of the potentially 

masking sound is important in 

determining any potential behavioral 

impacts. For example, low-frequency 

signals may have less effect on highfrequency echolocation sounds 

produced by odontocetes but are more 

likely to affect detection of mysticete 

communication calls and other 

potentially important natural sounds 

such as those produced by surf and 

some prey species. The masking of 

communication signals by 

anthropogenic noise may be considered 

as a reduction in the communication 

space of animals (e.g., Clark et al., 2009; 

Matthews, 2017) and may result in 

energetic or other costs as animals 

change their vocalization behavior (e.g., 

Miller et al., 2000; Foote et al., 2004; 

Parks et al., 2007; Di Iorio and Clark, 

2009; Holt et al., 2009). Masking can be 

reduced in situations where the signal 

and noise come from different 

directions (Richardson et al., 1995), 

through amplitude modulation of the 

signal, or through other compensatory 

behaviors (Houser and Moore, 2014). 

Masking can be tested directly in 

captive species (e.g., Erbe, 2008), but in 

wild populations it must be either 

modeled or inferred from evidence of 

masking compensation. There are few 

studies addressing real-world masking 

sounds likely to be experienced by 

marine mammals in the wild (e.g., 

Branstetter et al., 2013; Cholewiak et al., 

2018). 

The echolocation calls of toothed 

whales are subject to masking by highfrequency sound. Human data indicate 

low-frequency sound can mask highfrequency sounds (i.e., upward 

masking). Studies on captive 

odontocetes by Au et al. (1974, 1985, 

1993) indicate that some species may 

use various processes to reduce masking 

effects (e.g., adjustments in echolocation 

call intensity or frequency as a function 

of background noise conditions). There 

is also evidence that the directional 

hearing abilities of odontocetes are 

useful in reducing masking at the highfrequencies these cetaceans use to 

echolocate, but not at the low-tomoderate frequencies they use to 

communicate (Zaitseva et al., 1980). A 

study by Nachtigall and Supin (2008) 

showed that false killer whales adjust 

their hearing to compensate for ambient 

sounds and the intensity of returning 

echolocation signals. 

Impacts on signal detection, measured 

by masked detection thresholds, are not 

the only important factors to address 

when considering the potential effects 

of masking. As marine mammals use 

sound to recognize conspecifics, prey, 

predators, or other biologically 

significant sources (Branstetter et al., 

2016), it is also important to understand 

the impacts of masked recognition 

thresholds (often called ‘‘informational 

masking’’). Branstetter et al. (2016) 

measured masked recognition 

thresholds for whistle-like sounds of 

bottlenose dolphins and observed that 

they are approximately 4 dB above 

detection thresholds (energetic masking) 

for the same signals. Reduced ability to 

recognize a conspecific call or the 

acoustic signature of a predator could 

have severe negative impacts. 

Branstetter et al. (2016) observed that if 

‘‘quality communication’’ is set at 90 

percent recognition the output of 

communication space models (which 

are based on 50 percent detection) 

would likely result in a significant 

decrease in communication range. 

As marine mammals use sound to 

recognize predators (Allen et al., 2014; 

Cummings and Thompson, 1971; Cure ́

et al., 2015; Fish and Vania, 1971), the 

presence of masking noise may also 

prevent marine mammals from 

responding to acoustic cues produced 

by their predators, particularly if it 

occurs in the same frequency band. For 

example, harbor seals that reside in the 

coastal waters off British Columbia are 

frequently targeted by mammal-eating 

killer whales. The seals acoustically 

discriminate between the calls of 

mammal-eating and fish-eating killer 

whales (Deecke et al., 2002), a capability 

that should increase survivorship while 

reducing the energy required to attend 

to all killer whale calls. Similarly, 

sperm whales (Cure ́ et al., 2016; 

Isojunno et al., 2016), long-finned pilot 

whales (Visser et al., 2016), and 

humpback whales (Cure ́ et al., 2015) 

changed their behavior in response to 

killer whale vocalization playbacks; 

these findings indicate that some 

recognition of predator cues could be 

missed if the killer whale vocalizations 

were masked. The potential effects of 

masked predator acoustic cues depend 

on the duration of the masking noise 

and the likelihood of a marine mammal 

encountering a predator during the time 

that detection and recognition of 

predator cues are impeded. 

Redundancy and context can also 

facilitate detection of weak signals. 

These phenomena may help marine 

mammals detect weak sounds in the 

presence of natural or manmade noise. 

Most masking studies in marine 

mammals present the test signal and the 

masking noise from the same direction. 

The dominant background noise may be 

highly directional if it comes from a 

particular anthropogenic source such as 

a ship or industrial site. Directional 

hearing may significantly reduce the 

masking effects of these sounds by 

improving the effective signal-to-noise 

ratio. 

Masking affects both senders and 

receivers of acoustic signals and, at 

higher levels and longer duration, can 

potentially have long-term chronic 

effects on marine mammals at the 

population level as well as at the 

individual level. Low-frequency 

ambient sound levels have increased by 

as much as 20 dB (more than three times 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 529 

in terms of sound pressure level (SPL)) 

in the world’s ocean from pre-industrial 

periods, with most of the increase from 

distant commercial shipping 

(Hildebrand, 2009; Cholewiak et al., 

2018). All anthropogenic sound sources, 

but especially chronic and lowerfrequency signals (e.g., from commercial 

vessel traffic), contribute to elevated 

ambient sound levels, thus intensifying 

masking. 

In addition to making it more difficult 

for animals to perceive and recognize 

acoustic cues in their environment, 

anthropogenic sound presents separate 

challenges for animals that are 

vocalizing. When they vocalize, animals 

are aware of environmental conditions 

that affect the ‘‘active space’’ (or 

communication space) of their 

vocalizations, which is the maximum 

area within which their vocalizations 

can be detected before it drops to the 

level of ambient noise (Brenowitz, 2004; 

Brumm et al., 2004; Lohr et al., 2003). 

Animals are also aware of 

environmental conditions that affect 

whether listeners can discriminate and 

recognize their vocalizations from other 

sounds, which is more important than 

simply detecting that a vocalization is 

occurring (Brenowitz, 1982; Brumm et 

al., 2004; Dooling, 2004; Marten and 

Marler, 1977; Patricelli and Blickley, 

2006). Most species that vocalize have 

evolved with an ability to adjust their 

vocalizations to increase the signal-tonoise ratio, active space, and 

recognizability/distinguishability of 

their vocalizations in the face of 

temporary changes in background noise 

(Brumm et al., 2004; Patricelli and 

Blickley, 2006). Vocalizing animals can 

adjust their vocalization characteristics 

such as the frequency structure, 

amplitude, temporal structure, and 

temporal delivery (repetition rate), or 

ceasing to vocalize. 

Many animals will combine several of 

these strategies to compensate for high 

levels of background noise. 

Anthropogenic sounds that reduce the 

signal-to-noise ratio of animal 

vocalizations, increase the masked 

auditory thresholds of animals listening 

for such vocalizations, or reduce the 

active space of an animal’s vocalizations 

impair communication between 

animals. Most animals that vocalize 

have evolved strategies to compensate 

for the effects of short-term or temporary 

increases in background or ambient 

noise on their songs or calls. Although 

the fitness consequences of these vocal 

adjustments are not directly known in 

all instances, like most other trade-offs 

animals must make, some of these 

strategies likely come at a cost (Patricelli 

and Blickley, 2006; Noren et al., 2017; 

Noren et al., 2020). Shifting songs and 

calls to higher frequencies may also 

impose energetic costs (Lambrechts, 

1996). 

Marine mammals are also known to 

make vocal changes in response to 

anthropogenic noise. In cetaceans, 

vocalization changes have been reported 

from exposure to anthropogenic noise 

sources such as sonar, vessel noise, and 

seismic surveying (e.g., Gordon et al., 

2003; Di Iorio and Clark, 2009; Hatch et 

al., 2012; Holt et al., 2009; Holt et al., 

2011; Lesage et al., 1999; McDonald et 

al., 2009; Parks et al., 2007; Risch et al., 

2012; Rolland et al., 2012), as well as 

changes in the natural acoustic 

environment (Dunlop et al., 2014). 

Vocal changes can be temporary or can 

be persistent. For example, model 

simulation suggests that the increase in 

starting frequency for the North Atlantic 

right whale upcall over the last 50 years 

resulted in increased detection ranges 

between right whales. The frequency 

shift, coupled with an increase in call 

intensity by 20 dB, led to a call 

detectability range of less than 3 km to 

over 9 km (Tennessen and Parks, 2016). 

Holt et al. (2009) measured killer whale 

call source levels and background noise 

levels in the 1 to 40 kHz band and 

reported that the whales increased their 

call source levels by 1-dB SPL for every 

1-dB SPL increase in background noise 

level. Similarly, another study on St. 

Lawrence River belugas reported a 

similar rate of increase in vocalization 

activity in response to passing vessels 

(Scheifele et al., 2005). Di Iorio and 

Clark (2009) showed that blue whale 

calling rates vary in association with 

seismic sparker survey activity, with 

whales calling more on days with 

surveys than on days without surveys. 

They suggested that the whales called 

more during seismic survey periods as 

a way to compensate for the elevated 

noise conditions. 

In some cases, these vocal changes 

may have fitness consequences, such as 

an increase in metabolic rates and 

oxygen consumption, as observed in 

bottlenose dolphins when increasing 

their call amplitude (Holt et al., 2015). 

A switch from vocal communication to 

physical, surface-generated sounds such 

as pectoral fin slapping or breaching 

was observed for humpback whales in 

the presence of increasing natural 

background noise levels, indicating that 

adaptations to masking may also move 

beyond vocal modifications (Dunlop et 

al., 2010). 

While these changes all represent 

possible tactics by the sound-producing 

animal to reduce the impact of masking, 

the receiving animal can also reduce 

masking by using active listening 

strategies such as orienting to the sound 

source, moving to a quieter location, or 

reducing self-noise from hydrodynamic 

flow by remaining still. The temporal 

structure of noise (e.g., amplitude 

modulation) may also provide a 

considerable release from masking 

through comodulation masking release 

(a reduction of masking that occurs 

when broadband noise, with a 

frequency spectrum wider than an 

animal’s auditory filter bandwidth at the 

frequency of interest, is amplitude 

modulated) (Branstetter and Finneran, 

2008; Branstetter et al., 2013). Signal 

type (e.g., whistles, burst-pulse, sonar 

clicks) and spectral characteristics (e.g., 

frequency modulated with harmonics) 

may further influence masked detection 

thresholds (Branstetter et al., 2016; 

Cunningham et al., 2014). 

Masking is more likely to occur in the 

presence of broadband, relatively 

continuous noise sources, such as 

vessels. Several studies have shown 

decreases in marine mammal 

communication space and changes in 

behavior as a result of the presence of 

vessel noise. For example, right whales 

were observed to shift the frequency 

content of their calls upward while 

reducing the rate of calling in areas of 

increased anthropogenic noise (Parks et 

al., 2007) as well as increasing the 

amplitude (intensity) of their calls 

(Parks, 2009; Parks et al., 2011). Clark et 

al. (2009) observed that right whales’ 

communication space decreased by up 

to 84 percent in the presence of vessels. 

Cholewiak et al. (2018) also observed 

loss in communication space in 

Stellwagen National Marine Sanctuary 

for North Atlantic right whales, fin 

whales, and humpback whales with 

increased ambient noise and shipping 

noise. Although humpback whales off 

Australia did not change the frequency 

or duration of their vocalizations in the 

presence of ship noise, their source 

levels were lower than expected based 

on source level changes to wind noise, 

potentially indicating some signal 

masking (Dunlop, 2016). Multiple 

delphinid species have also been shown 

to increase the minimum or maximum 

frequencies of their whistles in the 

presence of anthropogenic noise and 

reduced communication space (e.g., 

Holt et al., 2009; Holt et al., 2011; 

Gervaise et al., 2012; Williams et al., 

2013; Hermannsen et al., 2014; Papale et 

al., 2015; Liu et al., 2017). While 

masking impacts are not a concern from 

lower intensity, higher frequency HRG 

surveys, some degree of masking would 

be expected in the vicinity of turbine 

pile driving and concentrated support 

vessel operation. However, pile driving 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
530 Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 

is an intermittent sound and would not 

be continuous throughout the day. 

Habituation and Sensitization 

Habituation can occur when an 

animal’s response to a stimulus wanes 

with repeated exposure, usually in the 

absence of unpleasant associated events 

(Wartzok et al., 2003). Animals are most 

likely to habituate to sounds that are 

predictable and unvarying. It is 

important to note that habituation is 

appropriately considered as a 

‘‘progressive reduction in response to 

stimuli that are perceived as neither 

aversive nor beneficial,’’ rather than as, 

more generally, moderation in response 

to human disturbance having a neutral 

or positive outcome (Bejder et al., 2009). 

The opposite process is sensitization, 

when an unpleasant experience leads to 

subsequent responses, often in the form 

of avoidance, at a lower level of 

exposure. 

Both habituation and sensitization 

require an ongoing learning process. As 

noted, behavioral state may affect the 

type of response. For example, animals 

that are resting may show greater 

behavioral change in response to 

disturbing sound levels than animals 

that are highly motivated to remain in 

an area for feeding (Richardson et al., 

1995; National Research Council (NRC), 

2003; Wartzok et al., 2003; Southall et 

al., 2019b). Controlled experiments with 

captive marine mammals have shown 

pronounced behavioral reactions, 

including avoidance of loud sound 

sources (e.g., Ridgway et al., 1997; 

Finneran et al., 2003; Houser et al., 

2013a; Houser et al., 2013b; Kastelein et 

al., 2018). Observed responses of wild 

marine mammals to loud impulsive 

sound sources (typically airguns or 

acoustic harassment devices) have been 

varied but often consist of avoidance 

behavior or other behavioral changes 

suggesting discomfort (Morton and 

Symonds, 2002; Richardson et al., 1995; 

Nowacek et al., 2007; Tougaard et al., 

2009; Brandt et al., 2011; Brandt et al., 

2012; Da ̈hne et al., 2013; Brandt et al., 

2014; Russell et al., 2016; Brandt et al., 

2018). 

Stone (2015) reported data from at-sea 

observations during 1,196 airgun 

surveys from 1994 to 2010. When large 

arrays of airguns (considered to be 500 

cubic inches (in3) or more) were firing, 

lateral displacement, more localized 

avoidance, or other changes in behavior 

were evident for most odontocetes. 

However, significant responses to large 

arrays were found only for the minke 

whale and fin whale. Behavioral 

responses observed included changes in 

swimming or surfacing behavior with 

indications that cetaceans remained 

near the water surface at these times. 

Behavioral observations of gray whales 

during an airgun survey monitored 

whale movements and respirations 

pre-, during, and post-seismic survey 

(Gailey et al., 2016). Behavioral state 

and water depth were the best ‘natural’ 

predictors of whale movements and 

respiration and after considering natural 

variation, none of the response variables 

were significantly associated with 

survey or vessel sounds. Many 

delphinids approach low-frequency 

airgun source vessels with no apparent 

discomfort or obvious behavioral change 

(e.g., Barkaszi et al., 2012), indicating 

the importance of frequency output in 

relation to the species’ hearing 

sensitivity. 

Physiological Responses 

An animal’s perception of a threat 

may be sufficient to trigger stress 

responses consisting of some 

combination of behavioral responses, 

autonomic nervous system responses, 

neuroendocrine responses, or immune 

responses (e.g., Selye, 1950; Moberg and 

Mench, 2000). In many cases, an 

animal’s first, and sometimes most 

economical (in terms of energetic costs), 

response is behavioral avoidance of the 

potential stressor. Autonomic nervous 

system responses to stress typically 

involve changes in heart rate, blood 

pressure, and gastrointestinal activity. 

These responses have a relatively short 

duration and may or may not have a 

significant long-term effect on an 

animal’s fitness. 

Neuroendocrine stress responses often 

involve the hypothalamus-pituitaryadrenal system. Virtually all 

neuroendocrine functions that are 

affected by stress—including immune 

competence, reproduction, metabolism, 

and behavior—are regulated by pituitary 

hormones. Stress-induced changes in 

the secretion of pituitary hormones have 

been implicated in failed reproduction, 

altered metabolism, reduced immune 

competence, and behavioral disturbance 

(e.g., Moberg, 1987; Blecha, 2000). 

Increases in the circulation of 

glucocorticoids are also equated with 

stress (Romano et al., 2004). 

The primary distinction between 

stress (which is adaptive and does not 

normally place an animal at risk) and 

‘‘distress’’ is the cost of the response. 

During a stress response, an animal uses 

glycogen stores that can be quickly 

replenished once the stress is alleviated. 

In such circumstances, the cost of the 

stress response would not pose serious 

fitness consequences. However, when 

an animal does not have sufficient 

energy reserves to satisfy the energetic 

costs of a stress response, energy 

resources must be diverted from other 

functions. This state of distress will last 

until the animal replenishes its 

energetic reserves sufficiently to restore 

normal function. 

Relationships between these 

physiological mechanisms, animal 

behavior, and the costs of stress 

responses are well studied through 

controlled experiments and for both 

laboratory and free-ranging animals 

(e.g., Holberton et al., 1996; Hood et al., 

1998; Jessop et al., 2003; Krausman et 

al., 2004; Lankford et al., 2005). Stress 

responses due to exposure to 

anthropogenic sounds or other stressors 

and their effects on marine mammals 

have also been reviewed (Fair and 

Becker, 2000; Romano et al., 2002b) 

and, more rarely, studied in wild 

populations (e.g., Lusseau and Bejder, 

2007; Romano et al., 2002a; Rolland et 

al., 2012). For example, Rolland et al. 

(2012) found that noise reduction from 

reduced ship traffic in the Bay of Fundy 

was associated with decreased stress in 

North Atlantic right whales. 

These and other studies lead to a 

reasonable expectation that some 

marine mammals will experience 

physiological stress responses upon 

exposure to acoustic stressors and that 

it is possible that some of these would 

be classified as ‘‘distress.’’ In addition, 

any animal experiencing TTS would 

likely also experience stress responses 

(NRC, 2003; NRC, 2017). Respiration 

naturally varies with different behaviors 

and variations in respiration rate as a 

function of acoustic exposure can be 

expected to co-occur with other 

behavioral reactions, such as a flight 

response or an alteration in diving. 

However, respiration rates in and of 

themselves may be representative of 

annoyance or an acute stress response. 

Mean exhalation rates of gray whales at 

rest and while diving were found to be 

unaffected by seismic surveys 

conducted adjacent to the whale feeding 

grounds (Gailey et al., 2007). Studies 

with captive harbor porpoises show 

increased respiration rates upon 

introduction of acoustic alarms 

(Kastelein et al., 2001; Kastelein et al., 

2006a) and emissions for underwater 

data transmission (Kastelein et al., 

2005). However, exposure of the same 

acoustic alarm to a striped dolphin 

under the same conditions did not elicit 

a response (Kastelein et al., 2006a), 

again highlighting the importance in 

understanding species differences in the 

tolerance of underwater noise when 

determining the potential for impacts 

resulting from anthropogenic sound 

exposure. 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 531 

Stranding 

The definition for a stranding under 

title IV of the MMPA is that (A) a marine 

mammal is dead and is (i) on a beach 

or shore of the United States, or (ii) in 

waters under the jurisdiction of the 

United States (including any navigable 

waters); or (B) a marine mammal is alive 

and is (i) on a beach or shore of the 

United States and is unable to return to 

the water, (ii) on a beach or shore of the 

United States and, although able to 

return to the water, is in need of 

apparent medical attention, or (iii) in 

the waters under the jurisdiction of the 

United States (including any navigable 

waters), but is unable to return to its 

natural habitat under its own power or 

without assistance (16 U.S.C. 1421h). 

Marine mammal strandings have been 

linked to a variety of causes, such as 

illness from exposure to infectious 

agents, biotoxins, or parasites; 

starvation; unusual oceanographic or 

weather events; or anthropogenic causes 

including fishery interaction, ship 

strike, entrainment, entrapment, sound 

exposure, or combinations of these 

stressors sustained concurrently or in 

series. There have been multiple events 

worldwide in which marine mammals 

(primarily beaked whales, or other deep 

divers) have stranded coincident with 

relatively nearby activities utilizing 

loud sound sources (primarily military 

training events), and five in which midfrequency active sonar has been more 

definitively determined to have been a 

contributing factor. 

There are multiple theories regarding 

the specific mechanisms responsible for 

marine mammal strandings caused by 

exposure to loud sounds. One primary 

theme is the behaviorally mediated 

responses of deep-diving species 

(odontocetes), in which their startled 

response to an acoustic disturbance (1) 

affects ascent or descent rates, the time 

they stay at depth or the surface, or 

other regular dive patterns that are used 

to physiologically manage gas formation 

and absorption within their bodies, such 

that the formation or growth of gas 

bubbles damages tissues or causes other 

injury, or (2) results in their flight to 

shallow areas, enclosed bays, or other 

areas considered ‘‘out of habitat,’’ in 

which they become disoriented and 

physiologically compromised. For more 

information on marine mammal 

stranding events and potential causes, 

please see the Mortality and Stranding 

section of NMFS Proposed Incidental 

Take Regulations for the Navy’s 

Training and Testing Activities in the 

Hawaii-Southern California Training 

and Testing Study Area (50 CFR part 

218, volume 83, No. 123, June 26, 2018). 

The construction activities proposed 

by US Wind (i.e., pile driving) do not 

inherently have the potential to result in 

marine mammal strandings. While 

vessel strikes could kill or injure a 

marine mammals (which may 

eventually strand), the required 

mitigation measures would reduce the 

potential for take from these activities to 

de minimus levels (see Proposed 

Mitigation section for more details). As 

described above, no mortality or serious 

injury is anticipated or proposed to be 

authorized from any Project activities. 

Of the strandings documented to date 

worldwide, NMFS is not aware of any 

being attributed to pile driving or to the 

types of HRG equipment proposed for 

use during the Project. Recently, there 

has been heightened interest in HRG 

surveys and their potential role in 

recent marine mammals strandings 

along the U.S. east coast. HRG surveys 

involve the use of certain sources to 

image the ocean bottom, which are very 

different from seismic airguns used in 

oil and gas surveys or tactical military 

sonar, in that they produce much 

smaller impact zones. Marine mammals 

may respond to exposure to these 

sources by, for example, avoiding the 

immediate area, which is why offshore 

wind developers have authorization to 

allow for Level B (behavioral) 

harassment, including US Wind. 

However, because of the combination of 

lower source levels, higher frequency, 

narrower beam-width (for some 

sources), and other factors, the area 

within which a marine mammal might 

be expected to be behaviorally disturbed 

by HRG sources is much smaller (by 

orders of magnitude) than the impact 

areas for seismic airguns or the military 

sonar with which a small number of 

marine mammal have been causally 

associated. Specifically, estimated 

harassment zones for HRG surveys are 

typically less than 200m (such as those 

associated with the Project), while zones 

for military mid-frequency active sonar 

or seismic airgun surveys typically 

extend for several kms ranging up to 10s 

of km. Further, because of this much 

smaller ensonified area, any marine 

mammal exposure to HRG sources is 

reasonably expected to be at 

significantly lower levels and shorter 

duration (associated with less severe 

responses), and there is no evidence 

suggesting, or reason to speculate, that 

marine mammals exposed to HRG 

survey noise are likely to be injured, 

much less strand, as a result. Last, all 

but one of the small number of marine 

mammal stranding events that have 

been causally associated with exposure 

to loud sound sources have been deepdiving toothed whale species (not 

mysticetes), which are known to 

respond differently to loud sounds. 

Potential Effects of Disturbance on 

Marine Mammal Fitness 

The different ways that marine 

mammals respond to sound are 

sometimes indicators of the ultimate 

effect that exposure to a given stimulus 

will have on the well-being (survival, 

reproduction, etc.) of an animal. There 

are numerous data relating the exposure 

of terrestrial mammals from sound to 

effects on reproduction or survival, and 

data for marine mammals continues to 

grow. Several authors have reported that 

disturbance stimuli may cause animals 

to abandon nesting and foraging sites 

(Sutherland and Crockford, 1993); may 

cause animals to increase their activity 

levels and suffer premature deaths or 

reduced reproductive success when 

their energy expenditures exceed their 

energy budgets (Daan et al., 1996; Feare, 

1976; Mullner et al., 2004); or may cause 

animals to experience higher predation 

rates when they adopt risk-prone 

foraging or migratory strategies (Frid 

and Dill, 2002). Each of these studies 

addressed the consequences of animals 

shifting from one behavioral state (e.g., 

resting or foraging) to another 

behavioral state (e.g., avoidance or 

escape behavior) because of human 

disturbance or disturbance stimuli. 

Attention is the cognitive process of 

selectively concentrating on one aspect 

of an animal’s environment while 

ignoring other things (Posner, 1994). 

Because animals (including humans) 

have limited cognitive resources, there 

is a limit to how much sensory 

information they can process at any 

time. The phenomenon called 

‘‘attentional capture’’ occurs when a 

stimulus (usually a stimulus that an 

animal is not concentrating on or 

attending to) ‘‘captures’’ an animal’s 

attention. This shift in attention can 

occur consciously or subconsciously 

(for example, when an animal hears 

sounds that it associates with the 

approach of a predator) and the shift in 

attention can be sudden (Dukas, 2002; 

van Rij, 2007). Once a stimulus has 

captured an animal’s attention, the 

animal can respond by ignoring the 

stimulus, assuming a ‘‘watch and wait’’ 

posture, or treat the stimulus as a 

disturbance and respond accordingly, 

which includes scanning for the source 

of the stimulus or ‘‘vigilance’’ 

(Cowlishaw et al., 2004). 

Vigilance is an adaptive behavior that 

helps animals determine the presence or 

absence of predators, assess their 

distance from conspecifics, or to attend 

cues from prey (Bednekoff and Lima, 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
532 Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 

1998; Treves, 2000). Despite those 

benefits, however, vigilance has a cost 

of time; when animals focus their 

attention on specific environmental 

cues, they are not attending to other 

activities such as foraging or resting. 

These effects have generally not been 

demonstrated for marine mammals, but 

studies involving fish and terrestrial 

animals have shown that increased 

vigilance may substantially reduce 

feeding rates (Saino, 1994; Beauchamp 

and Livoreil, 1997; Fritz et al., 2002; 

Purser and Radford, 2011). Animals will 

spend more time being vigilant, which 

may translate to less time foraging or 

resting, when disturbance stimuli 

approach them more directly, remain at 

closer distances, have a greater group 

size (e.g., multiple surface vessels), or 

when they co-occur with times that an 

animal perceives increased risk (e.g., 

when they are giving birth or 

accompanied by a calf). 

The primary mechanism by which 

increased vigilance and disturbance 

appear to affect the fitness of individual 

animals is by disrupting an animal’s 

time budget and, as a result, reducing 

the time they might spend foraging and 

resting (which increases an animal’s 

activity rate and energy demand while 

decreasing their caloric intake/energy). 

In a study of northern resident killer 

whales off Vancouver Island, exposure 

to boat traffic was shown to reduce 

foraging opportunities and increase 

traveling time (Holt et al., 2021). A 

simple bioenergetics model was applied 

to show that the reduced foraging 

opportunities equated to a decreased 

energy intake of 18 percent while the 

increased traveling incurred an 

increased energy output of 3–4 percent, 

which suggests that a management 

action based on avoiding interference 

with foraging might be particularly 

effective. 

On a related note, many animals 

perform vital functions, such as feeding, 

resting, traveling, and socializing, on a 

diel cycle (24-hour cycle). Behavioral 

reactions to noise exposure (such as 

disruption of critical life functions, 

displacement, or avoidance of important 

habitat) are more likely to be significant 

for fitness if they last more than one diel 

cycle or recur on subsequent days 

(Southall et al., 2007). Consequently, a 

behavioral response lasting less than 1 

day and not recurring on subsequent 

days is not considered particularly 

severe unless it could directly affect 

reproduction or survival (Southall et al., 

2007). It is important to note the 

difference between behavioral reactions 

lasting or recurring over multiple days 

and anthropogenic activities lasting or 

recurring over multiple days. For 

example, just because certain activities 

last for multiple days does not 

necessarily mean that individual 

animals will be either exposed to those 

activity-related stressors (i.e., sonar) for 

multiple days or further exposed in a 

manner that would result in sustained 

multi-day substantive behavioral 

responses. However, special attention is 

warranted where longer-duration 

activities overlay areas in which 

animals are known to congregate for 

longer durations for biologically 

important behaviors. 

There are few studies that directly 

illustrate the impacts of disturbance on 

marine mammal populations. Lusseau 

and Bejder (2007) present data from 

three long-term studies illustrating the 

connections between disturbance from 

whale-watching boats and populationlevel effects in cetaceans. In Shark Bay, 

Australia, the abundance of bottlenose 

dolphins was compared within adjacent 

control and tourism sites over three 

consecutive 4.5-year periods of 

increasing tourism levels. Between the 

second and third time periods, in which 

tourism doubled, dolphin abundance 

decreased by 15 percent in the tourism 

area and did not change significantly in 

the control area. In Fiordland, New 

Zealand, two populations (Milford and 

Doubtful Sounds) of bottlenose dolphins 

with tourism levels that differed by a 

factor of seven were observed and 

significant increases in traveling time 

and decreases in resting time were 

documented for both. Consistent shortterm avoidance strategies were observed 

in response to tour boats until a 

threshold of disturbance was reached 

(average of 68 minutes between 

interactions), after which the response 

switched to a longer-term habitat 

displacement strategy. For one 

population, tourism only occurred in a 

part of the home range. However, 

tourism occurred throughout the home 

range of the Doubtful Sound population 

and once boat traffic increased beyond 

the 68-minute threshold (resulting in 

abandonment of their home range/ 

preferred habitat), reproductive success 

drastically decreased (increased 

stillbirths) and abundance decreased 

significantly (from 67 to 56 individuals 

in a short period). 

In order to understand how the effects 

of activities may or may not impact 

species and stocks of marine mammals, 

it is necessary to understand not only 

what the likely disturbances are going to 

be but how those disturbances may 

affect the reproductive success and 

survivorship of individuals, and then 

how those impacts to individuals 

translate to population-level effects. 

Following on the earlier work of a 

committee of the U.S. NRC (NRC, 2005), 

New et al. (2014), in an effort termed the 

Potential Consequences of Disturbance 

(PCoD), outline an updated conceptual 

model of the relationships linking 

disturbance to changes in behavior and 

physiology, health, vital rates, and 

population dynamics. This framework is 

a four-step process progressing from 

changes in individual behavior and/or 

physiology, to changes in individual 

health, then vital rates, and finally to 

population-level effects. In this 

framework, behavioral and 

physiological changes can have direct 

(acute) effects on vital rates, such as 

when changes in habitat use or 

increased stress levels raise the 

probability of mother-calf separation or 

predation; indirect and long-term 

(chronic) effects on vital rates, such as 

when changes in time/energy budgets or 

increased disease susceptibility affect 

health, which then affects vital rates; or 

no effect to vital rates (New et al., 2014). 

Since the PCoD general framework 

was outlined and the relevant 

supporting literature compiled, multiple 

studies developing state-space energetic 

models for species with extensive longterm monitoring (e.g., southern elephant 

seals, North Atlantic right whales, 

Ziphiidae beaked whales, and 

bottlenose dolphins) have been 

conducted and can be used to 

effectively forecast longer-term, 

population-level impacts from 

behavioral changes. While these are 

very specific models with very specific 

data requirements that cannot yet be 

applied broadly to project-specific risk 

assessments for the majority of species, 

they are a critical first step towards 

being able to quantify the likelihood of 

a population level effect. Since New et 

al. (2014), several publications have 

described models developed to examine 

the long-term effects of environmental 

or anthropogenic disturbance of foraging 

on various life stages of selected species 

(e.g., sperm whale, Farmer et al., 2018; 

California sea lion, McHuron et al., 

2018; blue whale, Pirotta et al., 2018a; 

humpback whale, Dunlop et al., 2021). 

These models continue to add to 

refinement of the approaches to the 

PCoD framework. Such models also 

help identify what data inputs require 

further investigation. Pirotta et al. 

(2018b) provides a review of the PCoD 

framework with details on each step of 

the process and approaches to applying 

real data or simulations to achieve each 

step. 

Despite its simplicity, there are few 

complete PCoD models available for any 

marine mammal species due to a lack of 

data available to parameterize many of 

the steps. To date, no PCoD model has 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 533 

been fully parameterized with empirical 

data (Pirotta et al., 2018a) due to the fact 

they are data intensive and logistically 

challenging to complete. Therefore, 

most complete PCoD models include 

simulations, theoretical modeling, and 

expert opinion to move through the 

steps. For example, PCoD models have 

been developed to evaluate the effect of 

wind farm construction on the North 

Sea harbor porpoise populations (e.g., 

King et al., 2015; Nabe-Nielsen et al., 

2018). These models include a mix of 

empirical data, expert elicitation (King 

et al., 2015) and simulations of animals’ 

movements, energetics, and/or survival 

(New et al., 2014; Nabe-Nielsen et al., 

2018). 

PCoD models may also be approached 

in different manners. Dunlop et al. 

(2021) modeled migrating humpback 

whale mother-calf pairs in response to 

seismic surveys using both a forwards 

and backwards approach. While a 

typical forwards approach can 

determine if a stressor would have 

population-level consequences, Dunlop 

et al. demonstrated that working 

backwards through a PCoD model can 

be used to assess the ‘‘worst case’’ 

scenario for an interaction of a target 

species and stressor. This method may 

be useful for future management goals 

when appropriate data becomes 

available to fully support the model. In 

another example, harbor porpoise PCoD 

model investigating the impact of 

seismic surveys on harbor porpoise 

included an investigation on underlying 

drivers of vulnerability. Harbor porpoise 

movement and foraging were modeled 

for baseline periods and then for periods 

with seismic surveys as well; the 

models demonstrated that temporal (i.e., 

seasonal) variation in individual 

energetics and their link to costs 

associated with disturbances was key in 

predicting population impacts 

(Gallagher et al., 2021). 

Behavioral change, such as 

disturbance manifesting in lost foraging 

time, in response to anthropogenic 

activities is often assumed to indicate a 

biologically significant effect on a 

population of concern. However, as 

described above, individuals may be 

able to compensate for some types and 

degrees of shifts in behavior, preserving 

their health and thus their vital rates 

and population dynamics. For example, 

New et al. (2013) developed a model 

simulating the complex social, spatial, 

behavioral, and motivational 

interactions of coastal bottlenose 

dolphins in the Moray Firth, Scotland, 

to assess the biological significance of 

increased rate of behavioral disruptions 

caused by vessel traffic. Despite a 

modeled scenario in which vessel traffic 

increased from 70 to 470 vessels a year 

(a six-fold increase in vessel traffic) in 

response to the construction of a 

proposed offshore renewables’ facility, 

the dolphins’ behavioral time budget, 

spatial distribution, motivations, and 

social structure remain unchanged. 

Similarly, two bottlenose dolphin 

populations in Australia were also 

modeled over 5 years against a number 

of disturbances (Reed et al., 2020), and 

results indicated that habitat/noise 

disturbance had little overall impact on 

population abundances in either 

location, even in the most extreme 

impact scenarios modeled. 

By integrating different sources of 

data (e.g., controlled exposure data, 

activity monitoring, telemetry tracking, 

and prey sampling) into a theoretical 

model to predict effects from sonar on 

a blue whale’s daily energy intake, 

Pirotta et al. (2021) found that tagged 

blue whales’ activity budgets, lunging 

rates, and ranging patterns caused 

variability in their predicted cost of 

disturbance. This method may be useful 

for future management goals when 

appropriate data becomes available to 

fully support the model. Harbor 

porpoise movement and foraging were 

modeled for baseline periods and then 

for periods with seismic surveys as well; 

the models demonstrated that the 

seasonality of the seismic activity was 

an important predictor of impact 

(Gallagher et al., 2021). 

In their table 1, Keen et al. (2021) 

summarize the emerging themes in 

PCoD models that should be considered 

when assessing the likelihood and 

duration of exposure and the sensitivity 

of a population to disturbance (see table 

1 from Keen et al., 2021, below). The 

themes are categorized by life history 

traits (movement ecology, life history 

strategy, body size, and pace of life), 

disturbance source characteristics 

(overlap with biologically important 

areas, duration and frequency, and 

nature and context), and environmental 

conditions (natural variability in prey 

availability and climate change). Keen et 

al. (2021) then summarize how each of 

these features influence an assessment, 

noting, for example, that individual 

animals with small home ranges have a 

higher likelihood of prolonged or yearround exposure, that the effect of 

disturbance is strongly influenced by 

whether it overlaps with biologically 

important habitats when individuals are 

present, and that continuous disruption 

will have a greater impact than 

intermittent disruption. 

Nearly all PCoD studies and experts 

agree that infrequent exposures of a 

single day or less are unlikely to impact 

individual fitness, let alone lead to 

population level effects (Booth et al., 

2016; Booth et al., 2017; Christiansen 

and Lusseau, 2015; Farmer et al., 2018; 

Wilson et al., 2020; Harwood and Booth, 

2016; King et al., 2015; McHuron et al., 

2018; National Academies of Sciences, 

Engineering, and Medicine (NAS), 2017; 

New et al., 2014; Pirotta et al., 2018a; 

Southall et al., 2007; Villegas-Amtmann 

et al., 2015). As described through this 

proposed rule, NMFS expects that any 

behavioral disturbance that would occur 

due to animals being exposed to 

construction activity would be of a 

relatively short duration, with behavior 

returning to a baseline state shortly after 

the acoustic stimuli ceases or the animal 

moves far enough away from the source. 

Given this, and NMFS’ evaluation of the 

available PCoD studies, and the required 

mitigation discussed later, any such 

behavioral disturbance resulting from 

US Wind’s activities is not expected to 

impact individual animals’ health or 

have effects on individual animals’ 

survival or reproduction, thus no 

detrimental impacts at the population 

level are anticipated. Marine mammals 

may temporarily avoid the immediate 

area but are not expected to 

permanently abandon the area or their 

migratory or foraging behavior. Impacts 

to breeding, feeding, sheltering, resting, 

or migration are not expected nor are 

shifts in habitat use, distribution, or 

foraging success. 

Potential Effects From Vessel Strike 

Vessel collisions with marine 

mammals, also referred to as vessel 

strikes or ship strikes, can result in 

death or serious injury of the animal. 

Wounds resulting from ship strike may 

include massive trauma, hemorrhaging, 

broken bones, or propeller lacerations 

(Knowlton and Kraus, 2001). An animal 

at the surface could be struck directly by 

a vessel, a surfacing animal could hit 

the bottom of a vessel, or an animal just 

below the surface could be cut by a 

vessel’s propeller. Superficial strikes 

may not kill or result in the death of the 

animal. Lethal interactions are typically 

associated with large whales, which are 

occasionally found draped across the 

bulbous bow of large commercial ships 

upon arrival in port. Although smaller 

cetaceans are more maneuverable in 

relation to large vessels than are large 

whales, they may also be susceptible to 

strike. The severity of injuries typically 

depends on the size and speed of the 

vessel (Knowlton and Kraus, 2001; Laist 

et al., 2001; Vanderlaan and Taggart, 

2007; Conn and Silber, 2013). Impact 

forces increase with speed, as does the 

probability of a strike at a given distance 

(Silber et al., 2010; Gende et al., 2011). 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
534 Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 

The most vulnerable marine mammals 

are those that spend extended periods of 

time at the surface in order to restore 

oxygen levels within their tissues after 

deep dives (e.g., the sperm whale). In 

addition, some baleen whales seem 

generally unresponsive to vessel sound, 

making them more susceptible to vessel 

collisions (Nowacek et al., 2004). These 

species are primarily large, slow-moving 

whales. Marine mammal responses to 

vessels may include avoidance and 

changes in dive pattern (NRC, 2003). 

An examination of all known ship 

strikes from all shipping sources 

(civilian and military) indicates vessel 

speed is a principal factor in whether a 

vessel strike occurs and, if so, whether 

it results in injury, serious injury, or 

mortality (Knowlton and Kraus, 2001; 

Laist et al., 2001; Jensen and Silber, 

2003; Pace and Silber, 2005; Vanderlaan 

and Taggart, 2007; Conn and Silber, 

2013). In assessing records in which 

vessel speed was known, Laist et al. 

(2001) found a direct relationship 

between the occurrence of a whale 

strike and the speed of the vessel 

involved in the collision. The authors 

concluded that most deaths occurred 

when a vessel was traveling in excess of 

13 kn. 

Jensen and Silber (2003) detailed 292 

records of known or probable ship 

strikes of all large whale species from 

1975 to 2002. Of these, vessel speed at 

the time of collision was reported for 58 

cases. Of these 58 cases, 39 (or 67 

percent) resulted in serious injury or 

death (19 of those resulted in serious 

injury as determined by blood in the 

water, propeller gashes or severed 

tailstock, and fractured skull, jaw, 

vertebrae, hemorrhaging, massive 

bruising, or other injuries noted during 

necropsy and 20 resulted in death). 

Operating speeds of vessels that struck 

various species of large whales ranged 

from 2 to 51 kn. The majority (79 

percent) of these strikes occurred at 

speeds of 13 kn or greater. The average 

speed that resulted in serious injury or 

death was 18.6 kn. Pace and Silber 

(2005) found that the probability of 

death or serious injury increased rapidly 

with increasing vessel speed. 

Specifically, the predicted probability of 

serious injury or death increased from 

45 to 75 percent as vessel speed 

increased from 10 to 14 kn and 

exceeded 90 percent at 17 kn. Higher 

speeds during collisions result in greater 

force of impact and also appear to 

increase the chance of severe injuries or 

death. While modeling studies have 

suggested that hydrodynamic forces 

pulling whales toward the vessel hull 

increase with increasing speed (Clyne, 

1999; Knowlton et al., 1995), this is 

inconsistent with Silber et al. (2010), 

which demonstrated that there is no 

such relationship (i.e., hydrodynamic 

forces are independent of speed). 

In a separate study, Vanderlaan and 

Taggart (2007) analyzed the probability 

of lethal mortality of large whales at a 

given speed, showing that the greatest 

rate of change in the probability of a 

lethal injury to a large whale as a 

function of vessel speed occurs between 

8.6 and 15 kn. The chances of a lethal 

injury decline from approximately 80 

percent at 15 kn to approximately 20 

percent at 8.6 kn. At speeds below 11.8 

kn, the chances of lethal injury drop 

below 50 percent, while the probability 

asymptotically increases toward 100 

percent above 15 kn. 

The Jensen and Silber (2003) report 

notes that the Large Whale Ship Strike 

Database represents a minimum number 

of collisions, because the vast majority 

probably goes undetected or unreported. 

In contrast, the Project’s personnel are 

likely to detect any strike that does 

occur because of the required personnel 

training and lookouts, along with the 

inclusion of Protected Species 

Observers (as described in the Proposed 

Mitigation section), and they are 

required to report all ship strikes 

involving marine mammals. 

There are no known vessel strikes of 

marine mammals by any offshore wind 

energy vessel in the United States. 

Given the extensive mitigation and 

monitoring measures (see the Proposed 

Mitigation and Proposed Monitoring 

and Reporting section) that would be 

required of US Wind, NMFS believes 

that a vessel strike is not likely to occur. 

Potential Effects to Marine Mammal 

Habitat 

US Wind’s proposed activities could 

potentially affect marine mammal 

habitat through the introduction of 

impacts to the prey species of marine 

mammals (through noise, oceanographic 

processes, or reef effects), acoustic 

habitat (sound in the water column), 

water quality, and biologically 

important habitat for marine mammals. 

Effects on Prey 

Sound may affect marine mammals 

through impacts on the abundance, 

behavior, or distribution of prey species 

(e.g., crustaceans, cephalopods, fish, 

and zooplankton). Marine mammal prey 

varies by species, season, and location 

and, for some, is not well documented. 

Here, we describe studies regarding the 

effects of noise on known marine 

mammal prey. 

Fish utilize the soundscape and 

components of sound in their 

environment to perform important 

functions such as foraging, predator 

avoidance, mating, and spawning (e.g., 

Zelick and Mann, 1999; Fay, 2009). The 

most likely effects on fishes exposed to 

loud, intermittent, low-frequency 

sounds are behavioral responses (i.e., 

flight or avoidance). Short duration, 

sharp sounds (such as pile driving or 

airguns) can cause overt or subtle 

changes in fish behavior and local 

distribution. The reaction of fish to 

acoustic sources depends on the 

physiological state of the fish, past 

exposures, motivation (e.g., feeding, 

spawning, migration), and other 

environmental factors. Key impacts to 

fishes may include behavioral 

responses, hearing damage, barotrauma 

(pressure-related injuries), and 

mortality. While it is clear that the 

behavioral responses of individual prey, 

such as displacement or other changes 

in distribution, can have direct impacts 

on the foraging success of marine 

mammals, the effects on marine 

mammals of individual prey that 

experience hearing damage, barotrauma, 

or mortality is less clear, though 

obviously population scale impacts that 

meaningfully reduce the amount of prey 

available could have more serious 

impacts. 

Fishes, like other vertebrates, have a 

variety of different sensory systems to 

glean information from ocean around 

them (Astrup and Mohl, 1993; Astrup, 

1999; Braun and Grande, 2008; Carroll 

et al., 2017; Hawkins and Johnstone, 

1978; Ladich and Popper, 2004; Ladich 

and Schulz-Mirbach, 2016; Mann, 2016; 

Nedwell et al., 2004; Popper et al., 2003; 

Popper et al., 2005). Depending on their 

hearing anatomy and peripheral sensory 

structures, which vary among species, 

fishes hear sounds using pressure and 

particle motion sensitivity capabilities 

and detect the motion of surrounding 

water (Fay et al., 2008) (terrestrial 

vertebrates generally only detect 

pressure). Most marine fishes primarily 

detect particle motion using the inner 

ear and lateral line system while some 

fishes possess additional morphological 

adaptations or specializations that can 

enhance their sensitivity to sound 

pressure, such as a gas-filled swim 

bladder (Braun and Grande, 2008; 

Popper and Fay, 2011). 

Hearing capabilities vary considerably 

between different fish species with data 

only available for just over 100 species 

out of the 34,000 marine and freshwater 

fish species (Eschmeyer and Fong, 

2016). In order to better understand 

acoustic impacts on fishes, fish hearing 

groups are defined by species that 

possess a similar continuum of 

anatomical features, which result in 

varying degrees of hearing sensitivity 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 535 

(Popper and Hastings, 2009a). There are 

four hearing groups defined for all fish 

species (modified from Popper et al., 

2014) within this analysis, and they 

include: fishes without a swim bladder 

(e.g., flatfish, sharks, rays, etc.); fishes 

with a swim bladder not involved in 

hearing (e.g., salmon, cod, pollock, etc.); 

fishes with a swim bladder involved in 

hearing (e.g., sardines, anchovy, herring, 

etc.); and fishes with a swim bladder 

involved in hearing and high-frequency 

hearing (e.g., shad and menhaden). Most 

marine mammal fish prey species would 

not be likely to perceive or hear mid- or 

high-frequency sonars. While hearing 

studies have not been done on sardines 

and northern anchovies, it would not be 

unexpected for them to have hearing 

similarities to Pacific herring (up to 2– 

5 kHz) (Mann et al., 2005). Currently, 

less data are available to estimate the 

range of best sensitivity for fishes 

without a swim bladder. 

In terms of physiology, multiple 

scientific studies have documented a 

lack of mortality or physiological effects 

to fish from exposure to low- and midfrequency sonar and other sounds 

(Halvorsen et al., 2012a; J<rgensen et al., 

2005; Juanes et al., 2017; Kane et al., 

2010; Kvadsheim and Sevaldsen, 2005; 

Popper et al., 2007; Popper et al., 2016; 

Watwood et al., 2016). Techer et al. 

(2017) exposed carp in floating cages for 

up to 30 days to low-power 23 and 46 

kHz source without any significant 

physiological response. Other studies 

have documented either a lack of TTS 

in species whose hearing range cannot 

perceive sonar (such as Navy sonar), or 

for those species that could perceive 

sonar-like signals, any TTS experienced 

would be recoverable (Halvorsen et al., 

2012a; Ladich and Fay, 2013; Popper 

and Hastings, 2009a, 2009b; Popper et 

al., 2014; Smith, 2016). Only fishes that 

have specializations that enable them to 

hear sounds above about 2,500 Hz (2.5 

kHz), such as herring (Halvorsen et al., 

2012a; Mann et al., 2005; Mann, 2016; 

Popper et al., 2014), would have the 

potential to receive TTS or exhibit 

behavioral responses from exposure to 

mid-frequency sonar. In addition, any 

sonar induced TTS to fish whose 

hearing range could perceive sonar 

would only occur in the narrow 

spectrum of the source (e.g., 3.5 kHz) 

compared to the fish’s total hearing 

range (e.g., 0.01 kHz to 5 kHz). 

In terms of behavioral responses, 

Juanes et al. (2017) discuss the potential 

for negative impacts from anthropogenic 

noise on fish, but the author’s focus was 

on broader based sounds, such as ship 

and boat noise sources. Watwood et al. 

(2016) also documented no behavioral 

responses by reef fish after exposure to 

mid-frequency active sonar. Doksaeter et 

al. (2009; 2012) reported no behavioral 

responses to mid-frequency sonar (such 

as naval sonar) by Atlantic herring; 

specifically, no escape reactions 

(vertically or horizontally) were 

observed in free swimming herring 

exposed to mid-frequency sonar 

transmissions. Based on these results 

(Doksaeter et al., 2009; Doksaeter et al., 

2012; Sivle et al., 2012), Sivle et al. 

(2014) created a model in order to report 

on the possible population-level effects 

on Atlantic herring from active sonar. 

The authors concluded that the use of 

sonar poses little risk to populations of 

herring regardless of season, even when 

the herring populations are aggregated 

and directly exposed to sonar. Finally, 

Bruintjes et al. (2016) commented that 

fish exposed to any short-term noise 

within their hearing range might 

initially startle but would quickly return 

to normal behavior. 

Pile driving noise during construction 

is of particular concern as the very high 

sound pressure levels could potentially 

prevent fish from reaching breeding or 

spawning sites, finding food, and 

acoustically locating mates. A playback 

study in West Scotland revealed that 

there was a significant movement 

response to the pile driving stimulus in 

both species at relatively low received 

sound pressure levels (sole: 144–156 dB 

re 1mPa Peak; cod: 140–161 dB re 1 mPa 

Peak, particle motion between 6.51 * 

103 and 8.62 * 104 m/s2 peak) (MuellerBlenkle et al., 2010). The swimming 

speed of sole increased significantly 

during the playback of construction 

noise when compared to the playbacks 

of before and after construction. While 

not statistically significant, cod also 

displayed a similar behavioral response 

during before, during, and after 

construction playbacks. However, cod 

demonstrated a specific and significant 

freezing response at the onset and 

cessation of the playback recording. In 

both species, indications were present 

displaying directional movements away 

from the playback source. During wind 

farm construction in the eastern Taiwan 

Strait, Type 1 soniferous fish chorusing 

showed a relatively lower intensity and 

longer duration while Type 2 chorusing 

exhibited higher intensity and no 

changes in its duration. Deviation from 

regular fish vocalization patterns may 

affect fish reproductive success, cause 

migration, augmented predation, or 

physiological alterations. 

Occasional behavioral reactions to 

activities that produce underwater noise 

sources are unlikely to cause long-term 

consequences for individual fish or 

populations. The most likely impact to 

fish from impact and vibratory pile 

driving activities at the project areas 

would be temporary behavioral 

avoidance of the area. Any behavioral 

avoidance by fish of the disturbed area 

would still leave significantly large 

areas of fish and marine mammal 

foraging habitat in the nearby vicinity. 

The duration of fish avoidance of an 

area after pile driving stops is unknown, 

but a rapid return to normal 

recruitment, distribution and behavior 

is anticipated. In general, impacts to 

marine mammal prey species are 

expected to be minor and temporary due 

to the expected short daily duration of 

individual pile driving events and the 

relatively small areas being affected. 

SPLs of sufficient strength have been 

known to cause fish auditory 

impairment, injury, and mortality. 

Popper et al. (2014) found that fish with 

or without air bladders could 

experience TTS at 186 dB SELcum. 

Mortality could occur for fish without 

swim bladders at >216 dB SELcum. Those 

with swim bladders or at the egg or 

larvae life stage, mortality was possible 

at >203 dB SELcum. Other studies found 

that 203 dB SELcum or above caused a 

physiological response in other fish 

species (Casper et al., 2012; Halvorsen 

et al., 2012a; Halvorsen et al., 2012b; 

Casper et al., 2013a; Casper et al., 

2013b). However, in most fish species, 

hair cells in the ear continuously 

regenerate and loss of auditory function 

likely is restored when damaged cells 

are replaced with new cells. Halvorsen 

et al. (2012a) showed that a TTS of 4– 

6 dB was recoverable within 24 hours 

for one species. Impacts would be most 

severe when the individual fish is close 

to the source and when the duration of 

exposure is long. Injury caused by 

barotrauma can range from slight to 

severe and can cause death and is most 

likely for fish with swim bladders. 

Barotrauma injuries have been 

documented during controlled exposure 

to impact pile driving (Halvorsen et al., 

2012b; Casper et al., 2013a). 

As described in the Proposed 

Mitigation section below, US Wind 

would utilize a sound attenuation 

device which would reduce potential 

for injury to marine mammal prey. 

Other fish that experience hearing loss 

as a result of exposure to impulsive 

sound sources may have a reduced 

ability to detect relevant sounds such as 

predators, prey, or social vocalizations. 

However, PTS has not been known to 

occur in fishes and any hearing loss in 

fish may be as temporary as the 

timeframe required to repair or replace 

the sensory cells that were damaged or 

destroyed (Popper et al., 2005; Popper et 

al., 2014; Smith, 2006). It is not known 

if damage to auditory nerve fibers could 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
536 Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 

occur, and if so, whether fibers would 

recover during this process. In addition, 

most acoustic effects, if any, are 

expected to be short-term and localized. 

Long-term consequences for fish 

populations, including key prey species 

within the project area, would not be 

expected. 

Required soft-starts would allow prey 

and marine mammals to move away 

from the source prior to any noise levels 

that may physically injure prey and the 

use of the noise attenuation devices 

would reduce noise levels to the degree 

any mortality or injury of prey is also 

minimized. Use of bubble curtains, in 

addition to reducing impacts to marine 

mammals, for example, is a key 

mitigation measure in reducing injury 

and mortality of ESA-listed salmon on 

the U.S. west coast. However, we 

recognize some mortality, physical 

injury and hearing impairment in 

marine mammal prey may occur, but we 

anticipate the amount of prey impacted 

in this manner is minimal compared to 

overall availability. Any behavioral 

responses to pile driving by marine 

mammal prey are expected to be brief. 

We expect that other impacts, such as 

stress or masking, would occur in fish 

that serve as marine mammals prey 

(Popper et al., 2019); however, those 

impacts would be limited to the 

duration of impact pile driving, and, if 

prey were to move out the area in 

response to noise, these impacts would 

be minimized. 

In addition to fish, prey sources such 

as marine invertebrates could 

potentially be impacted by noise 

stressors as a result of the proposed 

activities. However, most marine 

invertebrates’ ability to sense sounds is 

limited. Invertebrates appear to be able 

to detect sounds (Pumphrey, 1950; 

Frings and Frings, 1967) and are most 

sensitive to low-frequency sounds 

(Packard et al., 1990; Budelmann and 

Williamson, 1994; Lovell et al., 2005; 

Mooney et al., 2010). Data on response 

of invertebrates such as squid, another 

marine mammal prey species, to 

anthropogenic sound is more limited 

(de Soto, 2016; Sole et al., 2017). Data 

suggest that cephalopods are capable of 

sensing the particle motion of sounds 

and detect low frequencies up to 1–1.5 

kHz, depending on the species, and so 

are likely to detect airgun noise (Kaifu 

et al., 2008; Hu et al., 2009; Mooney et 

al., 2010; Samson et al., 2014). Sole et 

al. (2017) reported physiological 

injuries to cuttlefish in cages placed atsea when exposed during a controlled 

exposure experiment to low-frequency 

sources (315 Hz, 139 to 142 dB re 1 

mPa2; 400 Hz, 139 to 141 dB re 1 mPa2). 

Fewtrell and McCauley (2012) reported 

squids maintained in cages displayed 

startle responses and behavioral changes 

when exposed to seismic airgun sonar 

(136–162 re 1 mPa2·s). Jones et al. (2020) 

found that when squid (Doryteuthis 

pealeii) were exposed to impulse pile 

driving noise, body pattern changes, 

inking, jetting, and startle responses 

were observed and nearly all squid 

exhibited at least one response. 

However, these responses occurred 

primarily during the first eight impulses 

and diminished quickly, indicating 

potential rapid, short-term habituation. 

Cephalopods have a specialized 

sensory organ inside the head called a 

statocyst that may help an animal 

determine its position in space 

(orientation) and maintain balance 

(Budelmann, 1992). Packard et al. 

(1990) showed that cephalopods were 

sensitive to particle motion, not sound 

pressure, and Mooney et al. (2010) 

demonstrated that squid statocysts act 

as an accelerometer through which 

particle motion of the sound field can be 

detected. Auditory injuries (lesions 

occurring on the statocyst sensory hair 

cells) have been reported upon 

controlled exposure to low-frequency 

sounds, suggesting that cephalopods are 

particularly sensitive to low-frequency 

sound (Andre et al., 2011; Sole et al., 

2013). Behavioral responses, such as 

inking and jetting, have also been 

reported upon exposure to lowfrequency sound (McCauley et al., 2000; 

Samson et al., 2014). Squids, like most 

fish species, are likely more sensitive to 

low-frequency sounds and may not 

perceive mid- and high-frequency 

sonars. 

With regard to potential impacts on 

zooplankton, McCauley et al. (2017) 

found that exposure to airgun noise 

resulted in significant depletion for 

more than half the taxa present and that 

there were two to three times more dead 

zooplankton after airgun exposure 

compared with controls for all taxa, 

within 1 km of the airguns. However, 

the authors also stated that in order to 

have significant impacts on r-selected 

species (i.e., those with high growth 

rates and that produce many offspring) 

such as plankton, the spatial or 

temporal scale of impact must be large 

in comparison with the ecosystem 

concerned, and it is possible that the 

findings reflect avoidance by 

zooplankton rather than mortality 

(McCauley et al., 2017). In addition, the 

results of this study are inconsistent 

with a large body of research that 

generally finds limited spatial and 

temporal impacts to zooplankton as a 

result of exposure to airgun noise (e.g., 

Dalen and Knutsen, 1987; Payne, 2004; 

Stanley et al., 2011). Most prior research 

on this topic, which has focused on 

relatively small spatial scales, has 

showed minimal effects (e.g., 

Kostyuchenko, 1973; Booman et al., 

1996; S#tre and Ona, 1996; Pearson et 

al., 1994; Bolle et al., 2012). 

A modeling exercise was conducted 

as a follow-up to the McCauley et al. 

(2017) study (as recommended by 

McCauley et al.), in order to assess the 

potential for impacts on ocean 

ecosystem dynamics and zooplankton 

population dynamics (Richardson et al., 

2017). Richardson et al. (2017) found 

that a full-scale airgun survey would 

impact copepod abundance within the 

survey area, but that effects at a regional 

scale were minimal (2 percent decline 

in abundance within 150 km of the 

survey area and effects not discernible 

over the full region). The authors also 

found that recovery within the survey 

area would be relatively quick (3 days 

following survey completion) and 

suggest that the quick recovery was due 

to the fast growth rates of zooplankton, 

and the dispersal and mixing of 

zooplankton from both inside and 

outside of the impacted region. The 

authors also suggest that surveys in 

areas with more dynamic ocean 

circulation in comparison with the 

study region and/or with deeper waters 

(i.e., typical offshore wind locations) 

would have less net impact on 

zooplankton. 

Notably, a recently described study 

produced results inconsistent with 

those of McCauley et al. (2017). 

Researchers conducted a field and 

laboratory study to assess if exposure to 

airgun noise affects mortality, predator 

escape response, or gene expression of 

the copepod Calanus finmarchicus 

(Fields et al., 2019). Immediate 

mortality of copepods was significantly 

higher, relative to controls, at distances 

of 5 m or less from the airguns. 

Mortality 1 week after the airgun blast 

was significantly higher in the copepods 

placed 10 m from the airgun but was not 

significantly different from the controls 

at a distance of 20 m from the airgun. 

The increase in mortality, relative to 

controls, did not exceed 30 percent at 

any distance from the airgun. Moreover, 

the authors caution that even this higher 

mortality in the immediate vicinity of 

the airguns may be more pronounced 

than what would be observed in freeswimming animals due to increased 

flow speed of fluid inside bags 

containing the experimental animals. 

There were no sub-lethal effects on the 

escape performance, or the sensory 

threshold needed to initiate an escape 

response, at any of the distances from 

the airgun that were tested. Whereas 

McCauley et al. (2017) reported an SEL 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 537 

of 156 dB at a range of 509–658 m, with 

zooplankton mortality observed at that 

range, Fields et al. (2019) reported an 

SEL of 186 dB at a range of 25 m, with 

no reported mortality at that distance. 

The presence of large numbers of 

turbines has been shown to impact 

meso- and sub-meso-scale water column 

circulation, which can affect the 

density, distribution, and energy 

content of zooplankton and thereby, 

their availability as marine mammal 

prey. Topside, atmospheric wakes result 

in wind speed reductions influencing 

upwelling and downwelling in the 

ocean while underwater structures such 

as WTG and OSS foundations may 

cause turbulent current wakes, which 

impact circulation, stratification, 

mixing, and sediment resuspension 

(Daewel et al., 2022). Overall, the 

presence of structures such as wind 

turbines is, in general, likely to result in 

certain oceanographic effects in the 

marine environment and may alter 

marine mammal prey, such as 

aggregations and distribution of 

zooplankton through changing the 

strength of tidal currents and associated 

fronts, changes in stratification, primary 

production, the degree of mixing, and 

stratification in the water column (Chen 

et al., 2021; Johnson et al., 2021; 

Christiansen et al., 2022; Dorrell et al., 

2022). 

US Wind intends to install up to 114 

WTG and 4 OSS foundations, with 

turbine operations commencing in 2025 

and all turbines being operational in 

2027. As described above, there is 

scientific uncertainty around the scale 

of oceanographic impacts (meters to 

kilometers) associated with turbine 

operation. The Project is located 

offshore of Maryland along the midAtlantic Bight, and the project area does 

not include key foraging grounds for 

marine mammals with planktonic diets 

(e.g., North Atlantic right whale), as all 

known prime foraging habitat is located 

much further north, off southern New 

England and north into Canada. This 

foraging area is approximately 544.1 km 

(338.1 mi) north of the project area, and 

it would be highly unlikely for this 

foraging area to be influenced by 

activities related to the proposed 

Project. 

Although the project area does not 

provide high-quality foraging habitat for 

plankton-feeding marine mammals, 

such as North Atlantic right whales, 

coastal Maryland may provide seasonal 

high-quality foraging habitat for 

piscivorous marine mammals, such as 

humpback whales. Generally speaking, 

and depending on the extent, impacts 

on prey could impact the distribution of 

marine mammals in an area, potentially 

necessitating additional energy 

expenditure to find and capture prey. 

However, at the temporal and spatial 

scales anticipated for this activity, any 

such impacts on prey are not expected 

to impact the reproduction or survival 

of any individual marine mammals. 

Although studies assessing the impacts 

of offshore wind development on 

marine mammals are limited, the 

repopulation of wind energy areas by 

harbor porpoises (Brandt et al., 2016; 

Lindeboom et al., 2011) and harbor seals 

(Lindeboom et al., 2011; Russell et al., 

2016) following the installation of wind 

turbines are promising. Overall, any 

impacts to marine mammal foraging 

capabilities due to effects on prey 

aggregation from the turbine presence 

and operation during the effective 

period of the proposed rule is likely to 

be limited. 

In general, impacts to marine mammal 

prey species are expected to be 

relatively minor and temporary due to 

the expected short daily duration of 

individual pile driving events and the 

relatively small areas being affected. In 

addition, NMFS does not expect HRG 

acoustic sources to impact fish and most 

sources are likely outside the hearing 

range of the primary prey species in the 

project area. 

Overall, the combined impacts of 

sound exposure and oceanographic 

impacts on marine mammal habitat 

resulting from the proposed activities 

would not be expected to have 

measurable effects on populations of 

marine mammal prey species. Prey 

species exposed to sound might move 

away from the sound source, experience 

TTS, experience masking of biologically 

relevant sounds, or show no obvious 

direct effects. 

Reef Effects 

The presence of monopile, post-piled 

jacket, and pin pile foundations, scour 

protection, and cable protection will 

result in a conversion of the existing 

sandy bottom habitat to a hard bottom 

habitat with areas of vertical structural 

relief. This could potentially alter the 

existing habitat by creating an ‘‘artificial 

reef effect’’ that results in colonization 

by assemblages of both sessile and 

mobile animals within the new hardbottom habitat (Wilhelmsson et al., 

2006; Reubens et al., 2013; Bergstro ̈m et 

al., 2014; Coates et al., 2014). This 

colonization by marine species, 

especially hard-substrate preferring 

species, can result in changes to the 

diversity, composition, and/or biomass 

of the area thereby impacting the 

trophic composition of the site 

(Wilhelmsson et al., 2010; Krone et al., 

2013; Bergstro ̈m et al., 2014; Hooper et 

al., 2017; Raoux et al., 2017; Harrison 

and Rousseau, 2020; Taormina et al., 

2020; Buyse et al., 2022a; ter Hofstede 

et al., 2022). 

Artificial structures can create 

increased habitat heterogeneity 

important for species diversity and 

density (Langhamer, 2012). The WTG, 

OSS, and meteorological tower 

foundations will extend through the 

water column, which may serve to 

increase settlement of meroplankton or 

planktonic larvae on the structures in 

both the pelagic and benthic zones 

(Boehlert and Gill, 2010). Fish and 

invertebrate species are also likely to 

aggregate around the foundations and 

scour protection which could provide 

increased prey availability and 

structural habitat (Boehlert and Gill, 

2010; Bonar et al., 2015). Further, 

instances of species previously 

unknown, rare, or nonindigenous to an 

area have been documented at artificial 

structures, changing the composition of 

the food web and possibly the 

attractability of the area to new or 

existing predators (Adams et al., 2014; 

de Mesel, 2015; Bishop et al., 2017; 

Hooper et al., 2017; Raoux et al., 2017; 

van Hal et al., 2017; Degraer et al., 2020; 

Fernandez-Betelu et al., 2022). Notably, 

there are examples of these sites 

becoming dominated by marine 

mammal prey species, such as filterfeeding species and suspension-feeding 

crustaceans (Andersson and O ̈ hman, 

2010; Slavik et al., 2019; Hutchison et 

al., 2020; Pezy et al., 2020; Mavraki et 

al., 2022). 

Numerous studies have documented 

significantly higher fish concentrations 

including species like cod and pouting 

(Trisopterus luscus), flounder 

(Platichthys flesus), eelpout (Zoarces 

viviparus), and eel (Anguilla anguilla) 

near in-water structures than in 

surrounding soft bottom habitat 

(Langhamer and Wilhelmsson, 2009; 

Bergstro ̈m et al., 2013; Reubens et al., 

2013). In the German Bight portion of 

the North Sea, fish were most densely 

congregated near the anchorages of 

jacket foundations, and the structures 

extending through the water column 

were thought to make it more likely that 

juvenile or larval fish encounter and 

settle on them (Rhode Island Coastal 

Resources Management Council, 2010; 

Krone et al., 2013). In addition, fish can 

take advantage of the shelter provided 

by these structures while also being 

exposed to stronger currents created by 

the structures, which generate increased 

feeding opportunities and decreased 

potential for predation (Wilhelmsson et 

al., 2006). The presence of the 

foundations and resulting fish 

aggregations around the foundations is 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
538 Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 

expected to be a long-term habitat 

impact, but the increase in prey 

availability could potentially be 

beneficial for some marine mammals. 

The most likely impact on marine 

mammal habitats from the project is 

expected to be from pile driving, which 

may affect marine mammal food sources 

such as forage fish and could also affect 

acoustic habitat effects on marine 

mammal prey (e.g., fish). 

Water Quality 

Temporary and localized reduction in 

water quality will occur as a result of inwater construction activities. Most of 

this effect will occur during pile driving 

and installation of the cables, including 

auxiliary work such as dredging and 

scour placement. These activities will 

disturb bottom sediments and may 

cause a temporary increase in 

suspended sediment in the project area. 

Currents should quickly dissipate any 

raised total suspended sediment (TSS) 

levels, and levels should return to 

background levels once the project 

activities in that area cease. No direct 

impacts on marine mammals are 

anticipated due to increased TSS and 

turbidity; however, turbidity within the 

water column has the potential to 

reduce the level of oxygen in the water 

and irritate the gills of prey fish species 

in the proposed project area. However, 

turbidity plumes associated with the 

project would be temporary and 

localized, and fish in the proposed 

project area would be able to move away 

from and avoid the areas where plumes 

may occur. Therefore, it is expected that 

the impacts on prey fish species from 

turbidity, and therefore on marine 

mammals, would be minimal and 

temporary. 

Equipment used by US Wind within 

the project area, including ships and 

other marine vessels, potentially 

aircrafts, and other equipment, are also 

potential sources of by-products (e.g., 

hydrocarbons, particulate matter, heavy 

metals). All equipment is properly 

maintained in accordance with 

applicable legal requirements. All such 

operating equipment meets Federal 

water quality standards, where 

applicable. Given these requirements, 

impacts to water quality are expected to 

be minimal. 

Acoustic Habitat 

Acoustic habitat is the soundscape, 

which encompasses all of the sound 

present in a particular location and 

time, as a whole when considered from 

the perspective of the animals 

experiencing it. Animals produce sound 

for, or listen for sounds produced by, 

conspecifics (communication during 

feeding, mating, and other social 

activities), other animals (finding prey 

or avoiding predators), and the physical 

environment (finding suitable habitats, 

navigating). Together, sounds made by 

animals and the geophysical 

environment (e.g., produced by 

earthquakes, lightning, wind, rain, 

waves) make up the natural 

contributions to the total acoustics of a 

place. These acoustic conditions, 

termed acoustic habitat, are one 

attribute of an animal’s total habitat. 

Soundscapes are also defined by, and 

acoustic habitat influenced by, the total 

contribution of anthropogenic sound. 

This may include incidental emissions 

from sources such as vessel traffic or 

may be intentionally introduced to the 

marine environment for data acquisition 

purposes (as in the use of airgun arrays) 

or for Navy training and testing 

purposes (as in the use of sonar and 

explosives and other acoustic sources). 

Anthropogenic noise varies widely in its 

frequency, content, duration, and 

loudness and these characteristics 

greatly influence the potential habitatmediated effects to marine mammals 

(please also see the previous discussion 

on Masking), which may range from 

local effects for brief periods of time to 

chronic effects over large areas and for 

long durations. Depending on the extent 

of effects to habitat, animals may alter 

their communications signals (thereby 

potentially expending additional 

energy) or miss acoustic cues (either 

conspecific or adventitious). Problems 

arising from a failure to detect cues are 

more likely to occur when noise stimuli 

are chronic and overlap with 

biologically relevant cues used for 

communication, orientation, and 

predator/prey detection (Francis and 

Barber, 2013). For more detail on these 

concepts, see: Barber et al., 2009; 

Pijanowski et al., 2011; Francis and 

Barber, 2013; Lillis et al., 2014. 

The term ‘‘listening area’’ refers to the 

region of ocean over which sources of 

sound can be detected by an animal at 

the center of the space. Loss of 

communication space concerns the area 

over which a specific animal signal, 

used to communicate with conspecifics 

in biologically important contexts (e.g., 

foraging, mating), can be heard, in 

noisier relative to quieter conditions 

(Clark et al., 2009). Lost listening area 

concerns the more generalized 

contraction of the range over which 

animals would be able to detect a 

variety of signals of biological 

importance, including eavesdropping on 

predators and prey (Barber et al., 2009). 

Such metrics do not, in and of 

themselves, document fitness 

consequences for the marine animals 

that live in chronically noisy 

environments. Long-term populationlevel consequences mediated through 

changes in the ultimate survival and 

reproductive success of individuals are 

difficult to study, and particularly so 

underwater. However, it is increasingly 

well documented that aquatic species 

rely on qualities of natural acoustic 

habitats, with researchers quantifying 

reduced detection of important 

ecological cues (e.g., Francis and Barber, 

2013; Slabbekoorn et al., 2010) as well 

as survivorship consequences in several 

species (e.g., Simpson et al., 2014; 

Nedelec et al., 2014). 

Potential Effects From Offshore Wind 

Farm Operational Noise 

Although this proposed rulemaking 

primarily covers the noise produced 

from construction activities relevant to 

the Maryland Offshore Wind Project 

offshore wind facility, operational noise 

was a consideration in NMFS’ analysis 

of the project, as all turbines would 

become operational within the effective 

dates of the rule (if issued). It is 

expected that all turbines would be 

operational in Q1 2028. Once 

operational, offshore wind turbines are 

known to produce continuous, nonimpulsive underwater noise, primarily 

below 1 kHz (Tougaard et al., 2020; 

Sto ̈ber and Thomsen, 2021). 

In both newer, quieter, direct-drive 

systems and older generation, geared 

turbine designs, recent scientific studies 

indicate that operational noise from 

turbines is on the order of 110 to 125 dB 

re 1 mPa root-mean-square sound 

pressure level (SPLrms) at an 

approximate distance of 50 m (Tougaard 

et al., 2020). Recent measurements of 

operational sound generated from wind 

turbines (direct drive, 6 MW, jacket 

foundations) at Block Island wind farm 

(BIWF) indicate average broadband 

levels of 119 dB at 50 m from the 

turbine, with levels varying with wind 

speed (HDR, Inc., 2019). Interestingly, 

measurements from BIWF turbines 

showed operational sound had less 

tonal components compared to 

European measurements of turbines 

with gear boxes. 

Tougaard et al. (2020) further stated 

that the operational noise produced by 

WTGs is static in nature and lower than 

noise produced by passing ships. This is 

a noise source in this region to which 

marine mammals are likely already 

habituated. Furthermore, operational 

noise levels are likely lower than those 

ambient levels already present in active 

shipping lanes, such that operational 

noise would likely only be detected in 

very close proximity to the WTG 

(Thomsen et al., 2006; Tougaard et al., 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 539 

2020). Similarly, recent measurements 

from a wind farm (3 MW turbines) in 

China found at above 300 Hz, turbines 

produced sound that was similar to 

background levels (Zhang et al., 2021). 

Other studies by Jansen and de Jong 

(2016) and Tougaard et al. (2009) 

determined that, while marine 

mammals would be able to detect 

operational noise from offshore wind 

farms (again, based on older 2 MW 

models) for several kilometers, they 

expected no significant impacts on 

individual survival, population 

viability, marine mammal distribution, 

or the behavior of the animals 

considered in their study (harbor 

porpoises and harbor seals). In addition, 

Madsen et al. (2006) found the intensity 

of noise generated by operational wind 

turbines to be much less than the noises 

present during construction, although 

this observation was based on a single 

turbine with a maximum power of 2 

MW. 

More recently, Sto ̈ber and Thomsen 

(2021) used monitoring data and 

modeling to estimate noise generated by 

more recently developed, larger (10 

MW) direct-drive WTGs. Their findings, 

similar to Tougaard et al. (2020), 

demonstrate that there is a trend that 

operational noise increases with turbine 

size. Their study predicts broadband 

source levels could exceed 170-dB 

SPLrms for a 10-MW WTG; however, 

those noise levels were generated based 

on geared turbines; newer turbines 

operate with direct drive technology. 

The shift from using gear boxes to direct 

drive technology is expected to reduce 

the levels by 10 dB. The findings in the 

Sto ̈ber and Thomsen (2021) study have 

not been experimentally validated, 

though the modeling (using largely 

geared turbines) performed by Tougaard 

et al. (2020) yields similar results for a 

hypothetical 10 MW WTG. 

Recently, Holme et al. (2023) 

cautioned that Tougaard et al. (2020) 

and Sto ̈ber and Thomsen (2021) 

extrapolated levels for larger turbines 

should be interpreted with caution since 

both studies relied on data from smaller 

turbines (0.45 to 6.15 MW) collected 

over a variety of environmental 

conditions. They demonstrated that the 

model presented in Tougaard et al. 

(2020) tends to potentially overestimate 

levels (up to approximately 8 dB) 

measured to those in the field, 

especially with measurements closer to 

the turbine for larger turbines. Holme et 

al. (2023) measured operational noise 

from larger turbines (6.3 and 8.3 MW) 

associated with three wind farms in 

Europe and found no relationship 

between turbine activity (power 

production, which is proportional to the 

blade’s revolutions per minute) and 

noise level, though it was noted that this 

missing relationship may have been 

masked by the area’s relatively high 

ambient noise sound levels. Sound 

levels (RMS) of a 6.3-MW direct-drive 

turbine were measured to be 117.3 dB 

at a distance of 70 m. However, 

measurements from 8.3 MW turbines 

were inconclusive as turbine noise was 

deemed to have been largely masked by 

ambient noise. 

Finally, operational turbine 

measurements are available from the 

Coastal Virginia Offshore Wind (CVOW) 

pilot pile project, where two 7.8 m 

monopile WTGs were installed (HDR, 

2023). Compared to BIWF, levels at 

CVOW were higher (10–30 dB) below 

120 Hz, believed to be caused by the 

vibrations associated with the monopile 

structure, while above 120 Hz levels 

were consistent among the two wind 

farms. 

Overall, noise from operating turbines 

would raise ambient noise levels in the 

immediate vicinity of the turbines; 

however, the spatial extent of increased 

noise levels would be limited. NMFS 

proposes to require US Wind to measure 

operational noise levels. US Wind did 

not request, and NMFS is not proposing 

to authorize, take incidental to 

operational noise from WTGs. 

Therefore, the topic is not discussed or 

analyzed further herein. 

Estimated Take of Marine Mammals 

This section provides an estimate of 

the number of incidental takes proposed 

for authorization through the 

regulations, which will inform both 

NMFS’ consideration of ‘‘small 

numbers’’ and the negligible impact 

determination. 

Harassment is the only type of take 

expected to result from these activities. 

Except with respect to certain activities 

not pertinent here, section 3(18) of the 

MMPA defines ‘‘harassment’’ as any act 

of pursuit, torment, or annoyance, 

which has the potential to injure a 

marine mammal or marine mammal 

stock in the wild (Level A harassment) 

or has the potential to disturb a marine 

mammal or marine mammal stock in the 

wild by causing disruption of behavioral 

patterns, including, but not limited to, 

migration, breathing, nursing, breeding, 

feeding, or sheltering (Level B 

harassment). 

Authorized takes would primarily be 

by Level B harassment, as noise from 

pile driving and HRG surveys, could 

result in behavioral disturbance of 

marine mammals that qualifies as take. 

Impacts such as masking and TTS can 

contribute to the disruption of 

behavioral patterns and are accounted 

for within those takes proposed for 

authorization. There is also some 

potential for auditory injury (Level A 

harassment) of all marine mammals 

except North Atlantic right whales. 

However, the amount of Level A 

harassment that US Wind requested, 

and NMFS proposes to authorize, is 

low. While NMFS is proposing to 

authorize Level A harassment and Level 

B harassment, the proposed mitigation 

and monitoring measures are expected 

to minimize the amount and severity of 

such taking to the extent practicable (see 

Proposed Mitigation and Proposed 

Monitoring and Reporting). 

As described previously, no serious 

injury or mortality is anticipated or 

proposed to be authorized incidental to 

the specified activities. Even without 

mitigation, both pile driving activities 

and HRG surveys would not have the 

potential to directly cause marine 

mammal mortality or serious injury. 

However, NMFS is proposing measures 

to more comprehensively reduce 

impacts to marine mammal species. 

While, in general, there is a low 

probability that mortality or serious 

injury of marine mammals could occur 

from vessel strikes, the mitigation and 

monitoring measures contained within 

this proposed rule are expected to avoid 

vessel strikes (see Proposed Mitigation 

section). No other activities have the 

potential to result in mortality or serious 

injury. 

For acoustic impacts, we estimate take 

by considering: (1) acoustic thresholds 

above which the best available science 

indicates marine mammals will be 

behaviorally harassed or incur some 

degree of permanent hearing 

impairment; (2) the area or volume of 

water that will be ensonified above 

these levels in a day; (3) the density or 

occurrence of marine mammals within 

these ensonified areas; and (4) the 

number of days of activities. We note 

that while these factors can contribute 

to a basic calculation to provide an 

initial prediction of potential takes, 

additional information that can 

qualitatively inform take estimates is 

also sometimes available (e.g., previous 

monitoring results or average group 

size). Below, we describe the factors 

considered here in more detail and 

present the proposed take estimates. 

As described below, there are 

multiple methods available to predict 

density or occurrence and, for each 

species and activity, the largest value 

resulting from the three take estimation 

methods described below (i.e., densitybased, PSO-based, or mean group size) 

was carried forward as the amount of 

take proposed for authorization, by 

Level B harassment. The amount of take 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
540 Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 

proposed for authorization, by Level A 

harassment, reflects the density-based 

exposure estimates and, for some 

species and activities, consideration of 

other data such as mean group size. 

Below, we describe NMFS’ acoustic 

thresholds, acoustic and exposure 

modeling methodologies, marine 

mammal density calculation 

methodology, occurrence information, 

and the modeling and methodologies 

applied to estimate take for each of the 

Project’s proposed construction 

activities. NMFS has carefully 

considered all information and analysis 

presented by US Wind, as well as all 

other applicable information and, based 

on the best available science, concurs 

that the estimates of the types and 

amounts of take for each species and 

stock are reasonable, and is proposing to 

authorize the amount requested. NMFS 

notes the take estimates described 

herein for foundation installation can be 

considered conservative as the estimates 

do not reflect the implementation of 

clearance and shutdown zones for any 

marine mammal species or stock. 

Acoustic Thresholds 

NMFS recommends the use of 

acoustic thresholds that identify the 

received level of underwater sound 

above which exposed marine mammals 

would be reasonably expected to be 

behaviorally harassed (Level B 

harassment) or to incur PTS of some 

degree (Level A harassment). A 

summary of all NMFS’ thresholds can 

be found at https://

www.fisheries.noaa.gov/national/ 

marine-mammal-protection/marinemammal-acoustic-technical-guidance. 

Level B Harassment 

Though significantly driven by 

received level, the onset of behavioral 

disturbance from anthropogenic noise 

exposure is also informed to varying 

degrees by other factors related to the 

source or exposure context (e.g., 

frequency, predictability, duty cycle, 

duration of the exposure, signal-to-noise 

ratio, distance to the source, ambient 

noise, and the receiving animal’s 

hearing, motivation, experience, 

demography, behavior at time of 

exposure, life stage, depth) and can be 

difficult to predict (e.g., Southall et al., 

2007, 2021; Ellison et al., 2012). Based 

on what the available science indicates 

and the practical need to use a threshold 

based on a metric that is both 

predictable and measurable for most 

activities, NMFS typically uses a 

generalized acoustic threshold based on 

received level to estimate the onset of 

behavioral harassment. 

NMFS generally predicts that marine 

mammals are likely to be behaviorally 

harassed in a manner considered to be 

Level B harassment when exposed to 

underwater anthropogenic noise above 

the received sound pressure levels 

(SPLRMS) of 120 dB for continuous 

sources (e.g., vibratory pile driving, 

drilling) and above the received SPLRMS

160 dB for non-explosive impulsive or 

intermittent sources (e.g., impact pile 

driving, scientific sonar). Generally 

speaking, Level B harassment take 

estimates based on these behavioral 

harassment thresholds are expected to 

include any likely takes by TTS as, in 

most cases, the likelihood of TTS occurs 

at distances from the source less than 

those at which behavioral harassment is 

likely. TTS of a sufficient degree can 

manifest as behavioral harassment, as 

reduced hearing sensitivity and the 

potential reduced opportunities to 

detect important signals (conspecific 

communication, predators, prey) may 

result in changes in behavioral patterns 

that would not otherwise occur. 

The proposed Project’s construction 

activities include the use of impulsive 

or intermittent sources (i.e., impact pile 

driving, some HRG acoustic sources); 

therefore, the 160-dB re 1 mPa (rms) 

threshold is applicable to our analysis. 

Level A Harassment 

NMFS’ Technical Guidance for 

Assessing the Effects of Anthropogenic 

Sound on Marine Mammal Hearing 

(Version 2.0, Technical Guidance) 

(NMFS, 2018) identifies dual criteria to 

assess auditory injury (Level A 

harassment) to five different marine 

mammal groups (based on hearing 

sensitivity) as a result of exposure to 

noise from two different types of 

sources (impulsive or non-impulsive). 

As dual metrics, NMFS considers onset 

of PTS (Level A harassment) to have 

occurred when either one of the two 

metrics is exceeded (i.e., metric 

resulting in the largest isopleth). As 

described above, US Wind’s proposed 

activities include the use of impulsive 

sources. NMFS’ thresholds identifying 

the onset of PTS are provided in table 

8. The references, analysis, and 

methodology used in the development 

of the thresholds are described in 

NMFS’ 2018 Technical Guidance, which 

may be accessed at https://

www.fisheries.noaa.gov/national/ 

marine-mammal-protection/marinemammal-acoustic-technical-guidance. 

TABLE 8—PERMANENT THRESHOLD SHIFT (PTS) ONSET THRESHOLDS

[NMFS, 2018] 

Hearing group 

PTS onset thresholds * 

(received level) 

Impulsive Non-impulsive 

Low-Frequency (LF) Cetaceans ................... Lp,0-pk,flat: 219 dB; LE,p, LF,24h: 183 dB ........................................... LE,p, LF,24h: 199 dB. 

Mid-Frequency (MF) Cetaceans ................... Lp,0-pk,flat: 230 dB; LE,p, MF,24h: 185 dB .......................................... LE,p, MF,24h: 198 dB. 

High-Frequency (HF) Cetaceans ................. Lp,0-pk,flat: 202 dB; LE,p, HF,24h: 155 dB .......................................... LE,p, HF,24h: 173 dB. 

Phocid Pinnipeds (PW) (Underwater) .......... Lp,0-pk.flat: 218 dB; LE,p, PW,24h: 185 dB .......................................... LE,p, PW,24h: 201 dB. 

Otariid Pinnipeds (OW) (Underwater) .......... Cell 9: Lp,0-pk,flat: 232 dB; LE,p, OW,24h: 203 dB .............................. Cell 10: LE,p, OW,24h: 219 dB. 

* Dual metric thresholds for impulsive sounds: Use whichever results in the largest isopleth for calculating PTS onset. If a non-impulsive sound 

has the potential of exceeding the peak sound pressure level thresholds associated with impulsive sounds, these thresholds are recommended 

for consideration. 

Note: Peak sound pressure level (Lp,0-pk) has a reference value of 1 μPa, and weighted cumulative sound exposure level (LE,p) has a reference value of 1μPa2s. In this table, thresholds are abbreviated to be more reflective of International Organization for Standardization standards 

(ISO, 2017). The subscript ‘‘flat’’ is included to indicate peak sound pressure are flat weighted or unweighted within the generalized hearing 

range of marine mammals (i.e., 7 Hz to 160 kHz). The subscript associated with cumulative sound exposure level thresholds indicates the designated marine mammal auditory weighting function (LF, MF, and HF cetaceans, and PW and OW pinnipeds) and that the recommended accumulation period is 24 hours. The weighted cumulative sound exposure level thresholds could be exceeded in a multitude of ways (i.e., varying 

exposure levels and durations, duty cycle). When possible, it is valuable for action proponents to indicate the conditions under which these 

thresholds will be exceeded. 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 541 

Below, we describe the assumptions 

and methodologies used to estimate 

take, in consideration of acoustic 

thresholds and appropriate marine 

mammals density and occurrence 

information, for WTG, OSS, and 

meteorological tower installation, and 

HRG surveys. Resulting distances to 

thresholds, densities used, activityspecific exposure estimates (as relevant 

to the analysis), and activity-specific 

take estimates can be found in each 

activity subsection below. At the end of 

this section, we present the amount of 

annual and 5-year take that US Wind 

requested, and NMFS proposes to 

authorize, from all activities combined. 

Acoustic and Exposure Modeling 

The predominant underwater noise 

associated with the construction of the 

Project results from impact pile driving. 

US Wind employed Marine Acoustic, 

Inc., (MAI) to conduct acoustic 

modeling to better understand sound 

fields produced during these activities 

(see appendix A of ITA Application). 

The basic acoustic modeling approach is 

to characterize the sounds produced by 

the source and determine how the 

sounds propagate within the 

surrounding water column. MAI derived 

surrogate source spectra for each pile 

type and conducted sophisticated 

propagation modeling (as described 

below). To assess the potential for take 

from impact pile driving, MAI also 

conducted animal movement modeling; 

MAI estimated species-specific 

exposure probability by considering the 

range- and depth-dependent sound 

fields in relation to animal movement in 

simulated representative construction 

scenarios. More details on these 

acoustic source modeling, propagation 

modeling and exposure modeling 

methods are described below. 

The amount of sound generated 

during pile driving varies with the 

energy required to drive piles to a 

desired depth and depends on the 

sediment resistance encountered. 

Sediment types with greater resistance 

require hammers that deliver higher 

energy strikes and/or an increased 

number of strikes relative to 

installations in softer sediment. 

Maximum sound levels usually occur 

during the last stage of impact pile 

driving where the greatest resistance is 

encountered (Betke, 2008). Therefore, 

variations in hammer energies must be 

taken into account during acoustic 

source modeling. 

For impact pile driving, MAI derived 

surrogate source spectra for each impact 

pile driving scenario based upon 

available measured or modeled source 

spectra for hammer energies and pile 

diameters similar to those expected for 

the Project impact pile driving activities 

(table 9). Source spectra (or a 

representative of sound by frequency) 

were then adjusted based upon pile 

diameters and hammer energies that 

would be used by US Wind using pile 

driving scaling laws (Von Pein et al., 

2022), which are derived from a large 

number of measurements for wide 

ranges of hammer energies, pile 

diameters, and other parameters. 

MAI used the predicted spectrum of 

an 11-m diameter monopile developed 

for the South Fork Wind Farm (Denes et 

al., 2018; Denes et al., 2021) as a 

surrogate source signature in modeling 

of the 11-m monopile for the WTG 

foundations for the Project. The 

surrogate spectrum was predicted 

assuming an IHC S-4000 hammer with 

a maximum strike energy of 4,000 kJ, 

while the planned scenario includes an 

11-m monopile with a hammer capable 

of a 4,400-kJ maximum strike energy of 

4,400 kJ. Hence, MAI adjusted the 

spectra accordingly to account for 

slightly higher maximum source levels. 

The expected difference in sound level 

between 4,000 and 4,400 kJ can be 

approximated using energy scaling laws 

(Von Pein et al., 2022), and is estimated 

to be minimal (0.4 dB). 

MAI used a 3-m post-piled pin pile 

source spectrum in the modeling for 

impact pile driving of OSS foundations 

that was based upon the mean of the 

measured spectra of a 6-m pile reported 

by Bruns et al. (2014) and a 3.5-m 

FINO2 pile reported by Matuschek and 

Betke (2009) (see appendix A of the 

LOA application for additional detail on 

deriving source spectra for the 3-m pin 

pile). The resulting representative 

source level for the 3-m pin pile (208 

dBSEL) is comparable to the estimated 

value for a 2.4-m diameter post-piled 

pin pile driven by a 1,700-kJ Menck 

hammer (209 dBSEL) measured by 

Molnar et al. (2020). Molnar et al. (2020) 

estimated this value by back calculating 

the source level assuming transmission 

loss of 15 * log10 (range) based upon a 

measured SEL of 188 dB at a range of 

25 m from the pile during uninitiated 

impact pile driving. This suggests that 

the modeling for the 3-m pin pile is 

representative of a post-piled pin pile. 

The spectrum derived for the 3-m pin 

pile was scaled to represent the 1.8 m 

pin piles for the Met tower based upon 

the maximum hammer energy and pile 

diameter using relationships presented 

in Von Pein et al. (2022). The 3-m postpiled pin pile source levels being scaled 

down by 8 dB and a SEL source level 

of 199 dB for the 1.8-m pin pile (see 

section 4.4, ‘‘Source Characterization,’’ 

in appendix A of the ITA application for 

a full description of scaling) (table 11). 

Once acoustic modeling for the 

monopile at a maximum hammer energy 

of 4,400 kJ was performed, the modeled 

sound fields were then adjusted by a 

broadband sound reduction to represent 

the lower strike energy levels (i.e., 1,100 

kJ, 2,200 kJ, and 3,300 kJ) planned for 

portions of the monopile installation. To 

account for the differences in hammer 

energies planned for use and the 

maximum hammer energy (4,400 kJ), the 

modeled spectra for the 4,400-kJ 

hammer was scaled using 10*log10(E1/ 

E2) (where E1 is the lower strike energy 

level and E2 is the modeled energy 

level), to represent each of the lower 

proposed hammer energies (Von Pein et 

al., 2022). This resulted in the 

application of scaling factors of ¥6, ¥3, 

and ¥1 dB to represent the 1,100 kJ, 

2,200 kJ, and 3,300 kJ hammer energies, 

respectively, as shown in table 10. The 

ramp up of hammer energy is accounted 

for when calculating the cumulative 

SEL over the installation of each 

monopile using the number of strikes at 

each energy level. The broadband 

scaling factor (table 10) was subtracted 

from the modeled received levels for the 

indicated number of strikes before the 

cumulative SEL was calculated. This 

hammer strike energy progression for 

monopile installation was considered in 

the calculation of the acoustic ranges 

and acoustic exposures. Although US 

Wind originally considered and 

modeled maximum hammer strikes at 

an energy of 4,400 kJ, the final hammer 

schedule (table 10) did not include any 

strikes at the 4,400 kJ energy level as US 

Wind has indicated they do not plan to 

use hammer energies above 3,300 kJ. 

SEL acoustic ranges assume a hammer 

schedule up to a maximum energy of 

3,300 kJ, however, peak and RMS 

acoustic ranges assume a hammer 

schedule up to a maximum energy of 4, 

400 kJ (tables 14 and 15). For additional 

details on surrogate source spectra 

development and scaling, please see 

section 4.4, ‘‘Source Characterization,’’ 

in appendix A of US Wind’s ITA 

application. 

US Wind would use at least two noise 

abatement systems (NAS) during all pile 

driving associated with foundation 

installations, such as a double bubble 

curtain or single bubble curtain and an 

encapsulated bubble or foam sleeve, to 

reduce sound levels. NAS, such as 

bubble curtains, are often used to 

decrease the sound levels radiated from 

a source. Hence, hypothetical 

broadband attenuation levels of 0 dB, 10 

dB, and 20 dB were incorporated into 

the foundation source models to gauge 

effects on the ranges to thresholds given 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
542 Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 

these levels of attenuation (appendix A 

of the ITA application). Although two 

attenuation levels were evaluated, 

NMFS anticipates that the noise 

attenuation systems ultimately chosen 

will be capable of reliably reducing 

source levels by 10 dB; therefore, this 

assumption was carried forward in this 

analysis for monopile, jacket, and Met 

tower foundation pile driving 

installation. See the Proposed 

Mitigation section for more information 

regarding the justification for the 10-dB 

assumption. 

Key modeling assumptions for the 

monopiles and pin piles are listed in 

table 10 (additional modeling details 

and input parameters can be found in 

appendix A of the ITA application). 

Hammer energy schedules for 

monopiles (11-m), 3-m pin piles, and 

1.8-m pin piles (are also provided in 

table 10 and the resulting broadband 

source levels of the monopiles and pin 

piles are presented in table 11. 

TABLE 9—SURROGATE SPECTRA HAMMER ENERGIES AND PILE DIAMETERS

Foundation type 

Maximum 

hammer 

energy 

(kJ) 

Representative foundation 

Representative 

hammer 

energy 

(kJ) 

Reference 

11-m Monopile ................................ 1 4,400 11-m monopile ............................... 4,400 Denes et al., 2021. 

3-m Pin Pile .................................... 1,500 6-m pin pile 2 .................................. (4) Bruns et al., 2014. 

3.5-m FINO2 pile 3 ......................... Matuschek and Betke, 2009. 

1.8-m Pin Pile ................................. 500 3-m Skirt Pile ................................. 1,500 MAI, 2022. 

1 US Wind confirmed with NMFS that their maximum hammer energy will not exceed 3,300 kJ (Jodziewicz, 2023). 

2 Measured at a distance of 15 m. 

3 Measured at a distance of 500 m. 

4 Hammer energies were not available. 

TABLE 10—KEY PILING ASSUMPTIONS AND HAMMER ENERGY SCHEDULES FOR MONOPILES AND PIN PILES

Foundation type 

Hammer 

energy 

(kJ) 

Duration 

at energy 

level 

(min) 

Strikes 

per minute 

Strike 

count 

Hammer 

energy 

scaling 

factor 

(dB) 

Seabed 

penetration 

depth 

(m) 

Piling 

time per 

day 

(min) 

Number of 

piles per 

day 

11-m Monopile 1 ................................................ 1,100 30 20 600 ¥6 50 120 1 

2,200 60 40 2,400 ¥3 

3,300 30 60 1,800 ¥1 1 4,400 .................... .................... .................... 0 

3-m Pin Pile ....................................................... 3 1,500 480 40 19,200 n/a 5 50–60 6 480 4 

1.8-m Pin Pile .................................................... 3 500 360 4 8.3 2,988 n/a 5 51–53 6 360 3 

1While US Wind would use a hammer capable of striking the pile at 4,400 kJ, US Wind has committed to not using hammer energies about 3,300 kJ (Jodziewicz, 

2023). Modeled sound fields were adjusted by broadband sound reduction to represent the lower strike energy levels planned for monopile installation. 2Assumed this maximum hammer energy for the duration of installation. 

3Although the fractional number of 8.3 hammer strikes per minute is unlikely to be accomplished during installation, this number instead of the rounded, more realistic value of 8 strikes per minute is included as it results in a higher number of total hammer blows than if the rounded blows per minute value were used. 4Subject to final design. 

5Piling time refers to all pin piles installed within a 24-hour period. 

TABLE 11—BROADBAND SOURCE LEVELS, ASSUMING 10-dB ATTENUATION, DERIVED FROM SOURCE MODELING

Pile type 

Max hammer 

energy 

(kJ) a

Source level (dB) at 1 m 

SELss SPL Source 

(dB) re 1μ 

Pa2 m2

Peak SPL 

(dB) re 1μ 

Pa 

RMS SPL 

(dB) re 1μ 

Pa 

11-m Monopile ............................. 4,400 214 262 224 Denes et al. (2018; 2021). 

3-m Pin Pile b c ............................. 1,500 198 249 208 Bruns et al., 2014; Matuschek and Betke, 2009. 

1.8 m Pin Pile c ............................. 500 189 237 199 MAI, 2022. 

SELss = single strike SEL. 

aAssumes MHU 4400 hammer. 

bBased upon measured spectra of a 6-m pile reported by Bruns et al. (2014). cBased upon measured spectra of a 3.5-m pile reported by Matuschek and Betke (2009). 

After calculating source levels, MAI 

used the Navy Standard Parabolic 

Equation (NSPE) propagation model to 

estimate distances to NMFS’ harassment 

thresholds. The NSPE is a modern 

iteration of the well-known Rangedependent Acoustic Model (RAM) 

(Collins, 1993). The propagation of 

sound through the environment can be 

modeled by predicting the acoustic 

propagation loss—a measure, in 

decibels, of the decrease in sound level 

between a source and a receiver some 

distance away. Geometric spreading of 

acoustic waves is the predominant way 

by which propagation loss occurs. 

Propagation loss also happens when the 

sound is absorbed and scattered within 

the water column, as well as absorbed, 

scattered, and reflected at the water 

surface and within the seabed. 

Propagation loss depends on the 

acoustic properties of the ocean and 

seabed and its value changes with 

frequency. 

A single representative location of 

intermediate water depth (27 m) was 

selected for the underwater acoustic 

propagation modeling analysis. A 

sensitivity analysis was conducted to 

assess the differences in acoustic 

propagation at the selected 

intermediate-depth model location (27 

m), the deepest location (42 m), and 

shallowest location (13 m) within the 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 543 

Project Area. The results of the 

sensitivity analysis indicated that 

although acoustic propagation was not 

significantly different between the sites, 

lower received levels were predicted at 

the shallowest and deepest locations 

relative to the intermediate depth 

modeling location. Therefore, of the 

three considered modeling locations, 

the intermediate depth (27 m) location 

was selected to provide the most 

conservative and representative 

modeling results. MAI included 

physical site parameters, such as 

bathymetry, water surface roughness, 

seasonal sound velocity profiles, wind 

speed, and sediment type/size into the 

acoustic propagation model. The model 

generated the predicted noise during 

impact pile driving scenarios for the 11- 

m monopiles, 3-m pin piles, and 1.8-m 

pin piles. The May sound velocity 

profile was selected to be representative 

of the proposed pile driving 

construction period as this profile 

represented the largest acoustic 

propagation ranges (see appendix A of 

the ITA application). Pile driving 

sources were included in the 

propagation model as vertical line 

arrays. The pile beampattern was 

created from a vertical line array of 

elements with 1-m spacing from the 

surface to the seafloor. This 

representative array was used to create 

a frequency-specific beampattern (see 

appendix A of the ITA application). 

MAI followed this propagation process 

for each one-third octave center 

frequency in the bands from 10 Hz to 25 

kHz with radials running at 10° 

intervals to a range of 50 km. Based 

upon the source levels derived for each 

pile driving source (table 11), the onethird octave band source levels were 

added to each transmission loss value to 

produce a received level value at each 

range, depth, and bearing point. The 

combined sound fields for each 

frequency were then summed to 

generate a representative broadband 

sound field. This process was followed 

for each radial around each pile driving 

source to produce an N * twodimensional grid of received sound 

levels in range, depth and bearing. The 

resulting predicted acoustic SEL field 

was assessed with the appropriate 

marine mammal weighting functions for 

low-frequency, mid-frequency, and 

high-frequency cetaceans as well as 

pinnipeds in water (NMFS, 2018). These 

weighting functions were applied to 

individual sound received levels to 

reflect the susceptibility of each hearing 

group to noise-induced threshold shifts. 

To estimate the probability of 

exposure of animals to sound above 

NMFS’ harassment thresholds during 

foundation installation, MAI integrated 

the sound fields generated from the 

source and propagation models 

described above with marine mammal 

species-typical behavioral parameters 

(e.g., dive parameters, swimming speed, 

and course/direction changes) using the 

Acoustic Integration Model (AIM) 

(Frankel et al., 2002). AIM is a Monte 

Carlo based statistical model in which 

multiple iterations of realistic 

predictions of acoustic source use as 

well as animal distribution and 

movement patterns are conducted to 

provide statistical predictions of 

estimated effects from exposure to 

underwater sound transmissions. For 

each species, separate AIM simulations 

were developed and iterated for each 

modeling scenario and activity location. 

During the simulations, animats 

(modeled receivers representing 

individual marine mammals) were 

randomly distributed in the model 

simulation area and the predicted 

received sound level was estimated 

every 30 seconds to create a history over 

a 24-hour period. Animats were 

programmed to reflect off the 

boundaries of the model simulation area 

and remain within this simulation area. 

The model simulation area was 

delineated by four boundaries 

consisting of lines of latitude (37.5° to 

39° N) and lines of longitude (73.75° to 

75.5° W). These lines extended one 

latitude or longitude beyond the model 

simulation area to ensure that the region 

was large enough to capture anticipated 

substantial behavior reactions and an 

adequate number of animats would be 

modeled in all directions. This model 

area box, which included the model 

simulation area, was approximately 

20,000 km2 in size. Animats were also 

pre-programmed to move every 30 

seconds based upon species-specific 

behaviors, yet were limited in 

movements by the coastline and 

minimum occurrence depth for each 

species, based upon scientific literature. 

Animat movement behavior parameters 

included diving, swimming, aversion, 

and residency patterns based upon 

existing scientific literature for each 

species in the model (see table B–1 in 

appendix A of the ITA application). 

Animat movement behavior parameters 

for seals were modeled based upon 

harbor seal parameters (see table B–1 in 

appendix A of the ITA application). At 

the end of each 30-second interval, the 

received sound level (in dB RMS) for 

each animat was recorded. 

The output of the simulation is the 

exposure history for each animat within 

the simulation, and the combined 

history of all animats gives a probability 

density function of exposure during the 

project. The acoustic exposure history 

for each animat was analyzed to 

produce Level A harassment and Level 

B harassment exposure estimates. MAI 

estimated the amount of potential 

acoustic exposures above NMFS’ Level 

A (PTS) harassment and Level B 

(behavioral) harassment thresholds 

predicted to occur within the Project 

area from any pile driving event (see 

below in section WTG, OSS, and Met 

tower Foundation Installation for more 

details). Once an animat received an 

exposure from a sound field greater than 

the Level A harassment (PTS) threshold, 

the animat was eliminated from further 

analysis; animats not exposed to sound 

fields greater than the Level A 

harassment threshold were further 

analyzed to determine whether the 

animat would be exposed to sound 

fields greater than the Level B 

harassment (behavioral) threshold. 

Therefore, animats were not counted as 

both Level A harassment and Level B 

harassment exposures. 

To obtain acoustic exposure estimates 

for each species per pile, the numbers 

of modeled animat sound exposures 

were multiplied by the ratio of the 

modeled animat density to the realworld marine mammal density estimate 

for the buffered Lease Area (Roberts et 

al., 2023, see below for more details on 

how a 5.25-km buffer zone around the 

Lease Area was calculated and densities 

were estimated). The animat exposure 

estimates per pile are the product of the 

number of modeled exposures 

multiplied by the ratio of real-world 

density per month (Roberts et al., 2023) 

to model density. The daily exposures 

were then multiplied by the planned 

number of piles driven each month and 

then summed for the year for each of 

years 1–3 when pile driving would take 

place. US Wind plans to install only one 

monopile per day, four 3-m pin piles 

per day, and three 1.8-m pin piles per 

day (for Met tower). 

Density and Occurrence 

In this section, we provide the 

information about marine mammal 

density, presence, and group dynamics 

that informed the take calculations for 

all activities. US Wind applied the 2022 

Duke University Marine Geospatial 

Ecology Laboratory Habitat-based 

Marine Mammal Density Models for the 

U.S. Atlantic (Duke Model-Roberts et 

al., 2016; Roberts et al., 2023) to 

estimate take from foundation 

installation and HRG surveys (please see 

each activity subsection below for the 

resulting densities). The models 

estimate absolute density (individuals/ 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
544 Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 

100 km2) by statistically correlating 

sightings reported on shipboard and 

aerial surveys with oceanographic 

conditions. For most marine mammal 

species, densities are provided on a 

monthly basis. Where monthly densities 

are not available (e.g., pilot whales), 

annual densities are provided. 

Moreover, some species are represented 

as guilds (e.g., seals (representing 

Phocidae spp., primarily harbor and 

gray seals and pilot whales 

(representing short-finned and longfinned pilot whales)). 

The Duke habitat-based density 

models delineate species’ density into 5 

* 5 km (3.1 * 3.1 mi) grid cells. US 

Wind calculated mean monthly (or 

annual) densities for each species for 

each grid cell within the Lease Area and 

5.25 km buffer perimeter around the 

Lease Area that represented the largest 

10-dB attenuated expected range to 

NMFS’ harassment thresholds. The 

buffer perimeter was calculated based 

upon the largest range to Level B 

harassment threshold, which was 5.25 

km for impact pile driving of 11-m 

monopiles at a maximum hammer 

energy of 4,400 kJ. This distance was 

added as a buffer surrounding the Lease 

Area for all pile driving and HRG 

activities, and marine mammal densities 

were compiled for this buffered area 

(see figure 6–1 in the LOA application). 

All 5 × 5 km grid cells in the models 

that fell within the analysis polygon 

were considered in the calculations. If 

the centroid of the grid cell, or a 

minimum of half the cell, fell within the 

buffered lease area boundary, the cell 

was included in the density analysis 

(see section 3.2 of appendix A of the 

ITA application for additional 

information on how the centroid of each 

grid cell was determined). 

Densities were computed monthly for 

each species where monthly densities 

were available. For the pilot whale guild 

(i.e., long-finned and short-finned), 

monthly densities are unavailable, so 

annual mean densities were used 

instead. Additionally, the models 

provide density for pilot whales and 

seals as guilds. To obtain density 

estimates for long-finned and shortfinned pilot whales, US Wind scaled the 

guild density by the relative abundance 

of each species in the Project Area based 

upon sighting, biopsy, and stranding 

data (Garrison and Rosel, 2017; Palka et 

al., 2021; Hayes et al., 2023; Maryland 

Marine Mammal Stranding Program, 

2023). Biopsy and stranding data 

indicated that short-finned pilot whales 

are more likely than long-finned pilot 

whales to occur along the Maryland 

coast (Garrison and Rosel, 2017; Hayes 

et al., 2023). Based on these data, US 

Wind partitioned total pilot whale 

exposures based upon the assumption 

that 60 percent of exposures would be 

to short-finned pilot whales and 40 

percent of exposures would be to longfinned pilot whales. 

The equation below shows how local 

occurrence scaling is applied to 

compute density for pilot whales. 

Dshort-finned = Dboth × (Nshort-finned/ 

(Nshort-finned + Nlong-finned)), 

where D represents density and N 

represents occurrence. 

Density estimates for gray seals, 

harbor seals, and harp seals were not 

scaled by local occurrence as limited atsea data was available for these seal 

species in the Project Area (i.e., no local 

abundance estimates could be 

calculated). Although harp seals are 

considered extralimital in the Project 

Area, the MD DNR and National 

Aquarium at Baltimore (NAB) have 

documented harp seal strandings 

inshore of the Lease Area (NAB, 2023a). 

Over the past 10 years, stranding reports 

of harp seals in Maryland have become 

more common in areas such as Ocean 

City (NAB, 2023b). Although stranding 

records for harbor and gray seals exist 

as well for coastal Maryland, stranding 

records may not accurately reflect the 

numbers and distribution of seals 

offshore in the vicinity of the Project 

Area. In addition, the Roberts et al. 

(2023) density data includes all three 

species of seals in the seal guild. MAI 

conducted animat modeling using 

harbor seal behavior parameters (see 

appendix B, ‘‘Animat Modeling 

Parameters,’’ of appendix A of the ITA 

application) and, while behavioral 

parameters may differ slightly between 

seal species, NMFS concurs that harbor 

seal behavior is a suitable proxy for all 

seals as any behavioral differences 

between seal species are not likely to be 

large enough to require separate 

modeling. Harbor seals are likely to be 

the prevalent seal species in the Project 

Area and, given the difficulty predicting 

the likely proportion of exposures by 

species, exposure estimates for seals are 

presented for gray seals, harbor seals, 

and harp seals collectively. 

The density models (Roberts et al., 

2023) also do not distinguish between 

bottlenose dolphin stocks and only 

provide densities for bottlenose 

dolphins as a species. For impact pile 

driving, take of each bottlenose dolphin 

stock was allocated based upon the 

progression of pile driving from the 

southeastern corner of Lease Area in 

year 1 (2025) towards the western 

portion of the Lease Area in years 2 and 

3, as described further in the WTG, OSS, 

and Met Tower Foundation Installation 

section. Mean monthly density 

estimates are provided in table 12. 

TABLE 12—MEAN MONTHLY MARINE MAMMAL DENSITY ESTIMATES (ANIMALS PER 100 km2) CONSIDERING A 5.25-km 

BUFFER AROUND THE LEASE AREA 1

Species Jan Feb March April May June July Aug Sept Oct Nov Dec 

North Atlantic right whale .................................. 0.075 0.076 0.063 0.045 0.008 0.003 0.001 0.001 0.002 0.004 0.011 0.036 

Fin whale ........................................................... 0.214 0.184 0.154 0.135 0.094 0.111 0.041 0.028 0.04 0.037 0.045 0.151 

Humpback whale ............................................... 0.091 0.062 0.083 0.187 0.142 0.102 0.02 0.011 0.027 0.112 0.143 0.088 

Minke whale ...................................................... 0.069 0.089 0.114 0.687 0.750 0.155 0.05 0.02 0.01 0.055 0.025 0.064 

Sei whale ........................................................... 0.029 0.021 0.034 0.061 0.02 0.005 0.001 0 0.001 0.006 0.017 0.046 

Killer whale 2 ................................................ 0.002 

Atlantic spotted dolphin ..................................... 0.003 0.001 0.002 0.013 0.046 0.09 0.396 1.505 0.475 0.335 0.243 0.032 

Pantropical spotted dolphin 2 ............................ 0.004 

Bottlenose dolphin 3 .......................................... 3.855 1.316 1.659 5.668 15.225 15.92 18.323 20.608 16.47 14.689 17.13 11.705 

Short-finned pilot whale and long-finned pilot 

whale 4 ........................................................... 0.039 

Common dolphin ............................................... 4.298 1.869 1.972 3.268 3.289 1.471 1.301 0.501 0.044 0.765 5.746 7.939 

Risso’s dolphin .................................................. 0.045 0.006 0.006 0.056 0.051 0.018 0.017 0.018 0.01 0.023 0.092 0.169 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 545 

TABLE 12—MEAN MONTHLY MARINE MAMMAL DENSITY ESTIMATES (ANIMALS PER 100 km2) CONSIDERING A 5.25-km 

BUFFER AROUND THE LEASE AREA 1—Continued 

Species Jan Feb March April May June July Aug Sept Oct Nov Dec 

Rough-toothed dolphin 2 .................................... 0.002 

Striped dolphin 2 .......................................... 0.004 

Harbor porpoise ................................................ 3.653 3.336 2.586 3.191 0.615 0.002 0.001 0.001 0 0 0.002 2.025 

Seals 4 ............................................................... 16.993 12.084 7.569 11.879 9.843 1.087 0.408 0.236 0.405 2.158 3.222 15.741 

1Species that were modeled as a representative group rather than as individual species. 

2Annual densities are shown for species with insufficient sightings to derive density estimates by month. 

3Two stocks of common bottlenose dolphin (the western North Atlantic migratory coastal stock and the western North Atlantic offshore stock) may occur in the 

Project area. Both stocks are presented here. 4 Densities are only available for the combined seal and pilot whale groups in the Roberts et al. (2023) dataset. Seals include harbor seals, gray seals, and harp 

seals were in the seal guild. 5 Density estimates are presented yet take is not requested for these species due to low density estimates and few occurrences in the Project area. 

For some species and activities, PSO 

survey data for the Lease Area (RPS, 

2023; Smultea, 2022) and group size 

data compiled from RPS (2013) and DoN 

(2017b) indicate that the density-based 

exposure estimates may be insufficient 

to account for the number of individuals 

of a species that may be encountered 

during the planned activities. This is 

particularly true for uncommon or rare 

species with very low densities in the 

models. Hence, consideration of other 

data is required to ensure the potential 

for take is adequately assessed. 

In cases where the acoustic exposure 

estimate for a species was less than the 

mean group size, the take request was 

increased to the mean group size (in 

some cases multiple groups were 

assumed) and rounded to the nearest 

integer (table 13). Requested take for 

pile driving activities was adjusted 

according to average group size in table 

13 and rounded to the nearest whole 

number. 

Additional detail regarding the 

density and occurrence as well as the 

assumptions and methodology used to 

estimate take for specific activities is 

included in the activity-specific 

subsections below and in section 6.1 of 

the ITA application. Average group 

sizes used in take estimates, where 

applicable, for all activities are provided 

in table 13. 

TABLE 13—AVERAGE MARINE MAMMAL GROUP SIZES USED IN TAKE ESTIMATE CALCULATIONS

Species Mean group size Source 1

Fin whale 2 3 .................................................................................................................................................... 1.64 RPS, 2023. 

North Atlantic right whale 3 ............................................................................................................................. 2.00 RPS, 2023. 

Humpback whale 3 .......................................................................................................................................... 1.95 RPS, 2023. 

Atlantic spotted dolphin 3 ................................................................................................................................ 5.89 RPS, 2023. 

Pantropical spotted dolphin 3 .......................................................................................................................... 4.33 RPS, 2023. 

Common dolphin 3 .......................................................................................................................................... 7.00 RPS, 2023. 

Killer whale 4 ................................................................................................................................................... 2.5 DoN, 2017. 

Long-finned pilot whale 3 ................................................................................................................................ 11.0 DoN, 2017. 

Short-finned pilot whale 3 ................................................................................................................................ 16.0 DoN, 2017. 

Risso’s dolphin 3 ............................................................................................................................................. 8.47 DoN, 2017. 

Rough-toothed dolphin 4 ................................................................................................................................. 5.50 DoN, 2017. 

Striped dolphin 4 .............................................................................................................................................. 45.59 DoN, 2017. 

Harbor porpoise 5 ............................................................................................................................................ 3.00 RPS, 2023. 

1PSO data from the Smultea Associate PSO interim report (Smultea, 2022) was not used to assess group sizes as the activity documented in 

the report occurred outside the pile driving and HRG micro-siting periods planned for the Project. 2For fin whales, US Wind adjusted take by Level A harassment according to group size for years 1 and 3. 

3 US Wind adjusted take by Level B harassment for these species according to group size. 

4For killer whales, rough-toothed dolphins, and striped dolphins, NMFS adjusted take by Level B harassment according to the assumption that 

one group of each species would be encountered per year of impact pile driving. 5For harbor porpoises, US Wind adjusted take by Level A harassment according to group size for years 2 and 3 and take by Level B harassment according to group size for years 1 and 3. 

WTG, OSS, and Met Tower Foundation 

Installation 

Here, we describe the results from the 

acoustic, exposure, and take estimate 

methodologies outlined above for WTG, 

OSS, and meteorological tower 

installation pile driving activities that 

have the potential to result in 

harassment of marine mammals. We 

present acoustic ranges to Level A 

harassment and Level B harassment 

thresholds, densities, exposure 

estimates and take estimates following 

the aforementioned assumptions (e.g., 

construction and hammer schedules). 

As previously described, MAI 

integrated the results from acoustic 

source and propagation modeling into 

an animal movement model to calculate 

acoustic ranges for 16 marine mammal 

species considered common in the 

project area. The acoustic ranges 

represent distances to NMFS’ 

harassment isopleths independent of 

movement of a receiver. The pile 

progression schedule (refer back to table 

3) was taken into account when 

calculating the acoustic ranges to SEL 

thresholds (see appendix A of the ITA 

application of additional details on 

calculations). The modeled sound fields 

represented the single strike SELs at the 

modeled strike energies (table 11). The 

single strike SEL fields were converted 

to cumulative SEL fields based on the 

different strike energy levels and the 

number of expected hammer blows at 

each energy. The difference between a 

single strike SEL and the cumulative 

SEL was calculated using 10 * log10

(number of strikes). MAI calculated 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
546 Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 

acoustic ranges for the 11-m monopile 

assuming one monopile would be 

installed per day using 4,800 impact 

hammer strikes (table 3). For the 3-m 

pin piles for the OSSs scenario, MAI 

calculated the acoustic ranges assuming 

4 pin piles would be installed per day 

with 19,200 hammer strikes each day 

(table 3). MAI calculated acoustic ranges 

for the 1.8-m pin piles for the Met tower 

foundation assuming 3 pin piles would 

be installed per day with an associated 

2,998 impact hammer strikes that day 

(table 3). The maximum received levelover-depth was calculated at each range 

step and along each radial. The 

maximum and 95th percentile acoustic 

range to the marine mammal regulatory 

thresholds were then calculated for each 

of the modeling scenarios (table 14). The 

maximum acoustic range value 

represents the greatest distance along 

any single radial. The 95th percentile 

acoustic range (R95%) is an improved 

representation of the range to the 

threshold as it eliminates major outliers 

and better represents all the modeled 

radials. All acoustic ranges presented to 

regulatory thresholds are the 95th 

percentile range. PTS peak sound 

pressure level thresholds and the Level 

B behavioral harassment threshold (160- 

dB RMS sound pressure level) represent 

instantaneous exposures. The distances 

to the PTS dB SEL threshold are likely 

an overestimate as it assumes an animal 

remains at the distance for the entire 

duration of pile driving (however, an 

animal could come closer for a shorter 

period of time and still incur PTS or an 

animal could move further away and, 

thus, not be exposure to the entire 

duration of piling in a 24-hour period 

that would result in the exceedance of 

the PTS SELcum threshold). Acoustic 

ranges to the Level A harassment and 

Level B harassment thresholds are 

shown in tables 14 and 15, respectively. 

TABLE 14—ACOUSTIC RANGES (R95%) IN METERS (m) TO MARINE MAMMAL LEVEL A HARASSMENT THRESHOLDS (SEL 

AND PEAK 1) DURING IMPACT PILE DRIVING 11-m MONOPILES, 3-m PIN PILES, AND 1.8-m PIN PILES, ASSUMING 10- 

dB ATTENUATION

Pile installed 

Maximum 

hammer 

energy 

(kJ) 

Activity 

duration 

(min/day) 

Distances to Level A harassment thresholds (m) 

Low-frequency 

cetaceans 

Mid-frequency 

cetaceans 

High-frequency 

cetaceans Phocids 

219 

Lp, pk

183 

LE, 24hr

230 

Lp, pk

185 

LE, 24hr

202 

Lp, pk

155 

LE, 24hr

218 

Lp, pk

185 

LE, 24hr

11 m Monopile .............................. 2 3,300 120 <50 2,900 <50 0 200 250 <50 100 

3 m Pin Piles ................................. 1,500 480 <50 1,400 <50 0 <50 100 <50 50 

1.8 m Pin Pile ................................ 500 240 <50 50 <50 0 <50 0 <50 0 

1SEL acoustic ranges assumed a maximum hammer energy of 3,300 kJ while peak acoustic ranges assumed a maximum hammer energy of 4,400 kJ. US Wind 

confirmed with NMFS that they would not utilize hammer energies above 3,300 kJ (Jodziewicz, 2023). 

TABLE 15—ACOUSTIC RANGES (R95%) IN METERS (m) TO MARINE MAMMAL LEVEL B HARASSMENT THRESHOLDS (160-dB 

SPL) DURING IMPACT PILE DRIVING 11-m MONOPILES, 3-m PIN PILES, AND 1.8-m PIN PILES, ASSUMING 10-dB ATTENUATION

Pile installed Hammer energy 

(kJ) 

Distance to Level B 

harassment threshold 

(m) (160 dB) 

11-m Monopile ..................................................................................................................................... 4,400 5,250 

3-m Pin Piles ....................................................................................................................................... 1,500 500 

1.8-m Pin Pile ...................................................................................................................................... 500 100 

To estimate take from foundation 

installation activities, US Wind used the 

pile installation construction schedule 

shown in table 16, assuming 22 total 

days of foundation installation activities 

during the MarWin campaign, 58 total 

days of pile installation activities during 

the Momentum Wind campaign, and 39 

total days of pile installation during the 

Future Development campaign. 

TABLE 16—PILE INSTALLATION CONSTRUCTION SCHEDULE USED FOR TAKE ESTIMATION

Campaign Year Structure Foundation 

type 

Number of 

piles 

Expected 

number of 

days to 

install 

foundation 

type 

Installation 

rate per 

day 

Total 

number of 

installation 

days for 

campaign 

MarWin ................................................... 2025 WTG ................. 11-m Monopile ....... 21 21 1 22 

OSS .................. 3-m Pin Piles ......... 4 1 4 

Momentum Wind .................................... 2026 WTG ................. 11-m Monopile ....... 55 55 1 58 

OSS .................. 3-m Pin Piles ......... 8 2 4 

Met tower ......... 1.8-m Pin Piles ...... 3 1 3 

Future Development ............................... 2027 WTG ................. 11-m Monopile ....... 38 38 1 39 

OSS .................. 3-m Pin Piles ......... 4 1 4 

To estimate the amount of Level A 

harassment and Level B harassment that 

may occur incidental to foundation 

installation, US Wind used the animat 

modeling described above to integrate 

the predicted received sound level 

fields of the impact pile driving 

resulting from the acoustic modeling of 

the impact pile driving sources (acoustic 

ranges) with the four-dimensional 

movements of marine mammals. US 

Wind used the modeled SEL and peak 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 547 

SEL received by each individual animat 

over the duration of the model 

simulation (24 hours) to calculate the 

potential for that animat to have been 

exposed to sound levels exceeding the 

Level A harassment threshold. To 

estimate the amount of Level B 

(behavioral) harassment that may occur 

incidental to foundation installation, US 

Wind used the modeled root mean 

square (RMS) sound pressure levels to 

estimate the potential for marine 

mammal behavioral responses for 

animats that did not experience 

exposure to sound levels that exceeded 

Level A harassment thresholds. 

Modeled results for Level A harassment 

and Level B harassment exposure 

estimates were subsampled to reflect the 

duty cycle of each construction 

activity’s source to create multiple 

estimates of sound exposure for each 

source and marine mammal 

combinations. The number of modeled 

exposures were multiplied by the ratio 

of real-world density and animat model 

densities to obtain per pile animat 

exposure estimates. US Wind calculated 

maximum acoustic exposure estimates 

on an annual basis according to the 

annual installation schedule (table 16) 

for the 11-m monopile, 3-m skirt pile, 

and 1.8-m pin pile, assuming a 10-dB 

sound level attenuation each year. As 

described above, MAI multiplied the 

final acoustic per pile exposure estimate 

for each modeled species by the number 

of piles to be installed per month to 

obtain a monthly exposure estimate for 

each species. To obtain annual exposure 

estimates, MAI summed the monthly 

exposure estimates for each modeled 

species for each year of pile driving 

(years 1–3). MAI conducted these 

calculations for both Level A 

harassment and Level B harassment 

exposure estimates for each modeled 

species. Table 17 identifies the amount 

of take calculated for impact installation 

of monopiles for WTGs, table 18 

identifies the amount of take calculated 

for impact installation of 3-m pin piles 

for jacket foundations for OSSs, and 

table 19 identifies the amount of take 

calculated for impact installation of 1.8- 

m pin piles for the Met tower. No take 

by Level A harassment is anticipated or 

proposed for authorization during 

impact pile driving of 3-m pin piles for 

OSSs (table 18) or 1.8-m pin piles for 

the Met tower (table 19). Take proposed 

for authorization for all impact pile 

driving activities combined across years 

1–3 and carried forward for this 

proposed rule as shown in table 20. 

Bottlenose dolphin estimated take by 

Level B harassment was distributed 

between the coastal stock and offshore 

stock based upon the where impact pile 

driving would take place within the 

Lease Area throughout years 1–3 and 

how pile driving locations may overlap 

the expected ranges of the coastal and 

offshore stocks. North of Cape Hatteras, 

NC, the coastal stocks of bottlenose 

dolphins are expected to occur in waters 

less than 25 m deep and within 34 km 

of shore (Kenney, 1990; Torres et al., 

2003). Impact pile driving would 

progress from the southeastern corner of 

the Lease Area in year 1 and extend 

west during years 2 and 3. During year 

1, impact pile driving would occur 

furthest offshore, with the ensonified 

zone above NMFS harassment threshold 

beyond the expected range of the coastal 

stock, therefore, US Wind allocated 100 

percent of estimated take by Level B 

harassment during year 1 to the offshore 

stock. During years 2 and 3, pile driving 

would take place further west than year 

1 and within the range of the coastal 

stock as well. As pile driving is 

expected to progress westward into 

shallower waters and further into the 

range of the coastal stock during years 

2 and 3, estimated take by Level B 

harassment would increase for the 

coastal stock as compared to the 

offshore stock as the pile driving 

locations progress west. US Wind 

distributed estimated take by Level B 

harassment between stocks for years 2 

and 3 as follows: year 2 (70 percent 

offshore stock, 30 percent coastal stock) 

and year 3 (15 percent offshore stock; 85 

percent coastal stock). 

For Atlantic spotted dolphins, it was 

expected that five groups would be 

observed during pile driving activities 

in year 1 and 10 groups would be 

observed in years 2 and 3 (RPS, 2023). 

Although acoustic exposures were 

calculated as zero for each species of 

pilot whales each year, based upon 

sighting data in the area (DoN, 2017), it 

was assumed that one pilot whale group 

of each species may be encountered. US 

Wind adjusted pilot whale requested 

take by Level B harassment for years 1 

to 3. For Risso’s dolphin, it was 

expected that two groups of nine would 

be observed for each year of pile driving 

(years 1 through 3) and taken by Level 

B harassment. Although killer whales, 

rough-toothed dolphins, and striped 

dolphins are expected to be rare in the 

Project Area due to habitat preferences, 

a very small amount of exposures (e.g., 

0.22) were modeled; therefore, it was 

assumed one group of each species may 

be encountered during the LOA period. 

For harbor porpoises, it was expected 

that one group of three (RPS, 2023) 

would be taken by Level A harassment 

in years 2 and 3 and one group of three 

would be taken by Level B harassment 

in years 1 and 3. US Wind adjusted 

requested take for harbor porpoises, 

accordingly. Year 2 request for take by 

Level B harassment for harbor porpoises 

during pile driving activities was not 

adjusted for group size as the estimated 

acoustic exposure was greater than the 

average expected group size, and the 

acoustic exposure estimate was rounded 

up to the nearest whole number. 

Correcting for group size for these 

species is used as a conservative 

measure to ensure all animals in a group 

are accounted for in the take request. 

TABLE 17—MODELED LEVEL A HARASSMENT AND LEVEL B HARASSMENT EXPOSURES ASSUMING 10-dB SOUND ATTENUATION DURING IMPACT PILE DRIVING OF 11-m MONOPILE FOUNDATIONS IN THE BUFFERED LEASE AREA OVER 3 

YEARS AND PROPOSED TAKE (IN PARENTHESES) 

Marine mammal species 

Level A harassment 

(SELcum) 6

Level B harassment 

(160 dBrms) 

Year 1 

(2025) 8

Year 2 

(2026) 9

Year 3 

(2027) 10

Year 1 

(2025) 8

Year 2 

(2026) 9

Year 3 

(2027) 10

North Atlantic right whale 1 2 ......................................................... 0.01 (0) 0.05 (0) 0.02 (0) 3 0.06 (2) 3 0.24 (2) 3 0.08 (2) 

Fin whale 1 ..................................................................................... 3 0.39 (2) 3 1.16 (2) 3 0.68 (2) 4 3.94 (4) 4 11.57 (12) 4 6.83 (7) 

Humpback whale ........................................................................... 3 0.42 (2) 3 1.55 (2) 3 0.67 (2) 4 2.52 (3) 4 9.29 (10) 4 4.05 (5) 

Minke whale .................................................................................. 4 0.49 (1) 4 5.55 (6) 4 1.11 (2) 4 2.96 (3) 4 33.31 (34) 4 6.66 (7) 

Sei whale 1 .................................................................................... 4 0.1 (1) 4 0.12 (1) 4 0.02 (1) 4 0.11 (1) 4 0.83 (1) 4 0.17 (1) 

Killer whale .................................................................................... 0 (0) 0 (0) 0 (0) 3 0.08 (3) 3 0.22 (3) 3 0.15 (3) 

Atlantic spotted dolphin ................................................................. 0 (0) 0 (0) 0 (0) 3 14.07 (24) 3 38.86 (54) 3 50.75 (54) 

Bottlenose dolphin (offshore stock/coastal stock) 5 ...................... 0 (0) 0 (0) 0 (0) 4 846.85 (847) 4 2,320.67 (2,321) 4 1,711.04 (1,721) 

Common dolphin ........................................................................... 0 (0) 0 (0) 0 (0) 4 28.63 (29) 4 233.12 (234) 4 96.48 (97) 

Long-finned pilot whale ................................................................. 0 (0) 0 (0) 0 (0) 3 0 (11) 3 0 (11) 3 0 (11) 

Short-finned pilot whale ................................................................ 0 (0) 0 (0) 0 (0) 3 0 (16) 3 0 (16) 3 0 (16) 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
548 Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 

TABLE 17—MODELED LEVEL A HARASSMENT AND LEVEL B HARASSMENT EXPOSURES ASSUMING 10-dB SOUND ATTENUATION DURING IMPACT PILE DRIVING OF 11-m MONOPILE FOUNDATIONS IN THE BUFFERED LEASE AREA OVER 3 

YEARS AND PROPOSED TAKE (IN PARENTHESES)—Continued 

Marine mammal species 

Level A harassment 

(SELcum) 6

Level B harassment 

(160 dBrms) 

Year 1 

(2025) 8

Year 2 

(2026) 9

Year 3 

(2027) 10

Year 1 

(2025) 8

Year 2 

(2026) 9

Year 3 

(2027) 10

Pantropical spotted dolphin ........................................................... 0 (0) 0 (0) 0 (0) 3 0.17 (5) 3 0.45 (5) 3 0.31 (5) 

Risso’s dolphin .............................................................................. 0 (0) 0 (0) 0 (0) 3 0.79 (9) 3 4.33 (9) 3 1.94 (9) 

Rough toothed dolphin .................................................................. 0 (0) 0 (0) 0 (0) 3 0.04 (6) 3 0.11 (6) 3 0.08 (6) 

Striped dolphin .............................................................................. 0 (0) 0 (0) 0 (0) 3 0.17 (46) 3 0.45 (46) 3 0.31 (46) 

Harbor porpoise 6 .......................................................................... 0 (0) 3 1.19 (3) 3 0.01 (3) 3 0.03 (3) 3 15.83 (16) 3 0.08 (3) 

Gray seal 5 ..................................................................................... 0 (0) 0 (0) 0 (0) 4 17.87 (18) 4 234.31 (235) 4 30.02 (31) 

Harbor seal 5.

Harp seal 5.

1 Listed as Endangered under the Endangered Species Act (ESA) 

2 Level A harassment exposures were initially estimated for this species, but due to the mitigation measures that US Wind will be required to abide by, no Level A 

harassment take is expected, nor proposed to be authorized. 3Proposed take adjusted according to group size in table 13. 

4Proposed take rounded to the nearest whole number. 

5Two stocks of common bottlenose dolphin (the western North Atlantic migratory coastal stock and the western North Atlantic offshore stock) may occur in the 

Project area. Both stocks are presented together here. 6Peak levels were not considered because SEL distances were larger than peak in all cases, with the exception of harbor porpoise. Peak exposure estimates were 

greater than the cumulative SEL exposure estimates for harbor porpoises due to the frequency weighting of the SEL-based metric and a lower peak threshold for 

high-frequency cetaceans compared to other marine mammal hearing groups. 7Exposure estimates include harbor seals, gray seals, and harp seals combined. 

8 During the MarWin campaign in year 1, US Wind plans to install 21 11-m monopiles and 4 3-m pin piles. 

9 During the Momentum Wind campaign in year 2, US Wind plans to install 55 11-m monopiles, 8 3-m pin piles, and 3 1.8-m pin piles. 10 During the Future Development campaign in year 3, US Wind plans to install 38 11-m monopiles and 4 3-m pin piles. 

TABLE 18—MODELED LEVEL B HARASSMENT EXPOSURES (ASSUMING 10-dB SOUND ATTENUATION) DUE TO IMPACT PILE

DRIVING OF 3-m PIN PILES IN THE BUFFERED LEASE AREA OVER 3 YEARS 1 AND PROPOSED TAKE 8

Marine mammal species 

Level B harassment (160 dBrms) 

Year 1 (2025) 5 Year 2 (2026) 6 Year 3 (2027) 7

Exposure 

estimate 

Proposed 

take 

Exposure 

estimate 

Proposed 

take 

Exposure 

estimate 

Proposed 

take 

North Atlantic right whale 2 .............................................. 0 0 0 0 0 0 

Fin whale 2 3 ..................................................................... 0.03 2 0.06 2 0.03 2 

Humpback whale 3 ........................................................... 0.01 2 0.01 2 0.01 2 

Minke whale 4 ................................................................... 0.04 1 0.08 1 0.04 1 

Sei whale 2 ....................................................................... 0 0 0 0 0 0 

Killer whale ....................................................................... 0 0 0 0 0 0 

Atlantic spotted dolphin 3 ................................................. 0.17 6 0.35 6 0.17 6 

Bottlenose dolphin (offshore stock/coastal stock) 4 5 ....... 9.53 10 19.06 19 9.53 10 

Common dolphin 3 ............................................................ 0.57 7 1.14 7 0.57 7 

Long-finned pilot whale .................................................... 0 0 0 0 0 0 

Short-finned pilot whale ................................................... 0 0 0 0 0 0 

Pantropical spotted dolphin ............................................. 0 0 0 0 0 0 

Risso’s dolphin 3 ............................................................... 0.01 9 0.03 9 0.01 9 

Rough toothed dolphin ..................................................... 0 0 0 0 0 0 

Striped dolphin ................................................................. 0 0 0 0 0 0 

Harbor porpoise ............................................................... 0 0 0 0 0 0 

Gray seal 6 ....................................................................... 0.08 0 0.16 0 0.08 0 

Harbor seal 6.

Harp seal 6.

1 Modeled acoustic exposure estimates for all species were zero for take by Level A harassment. Therefore, no take by Level A harassment is 

anticipated or proposed for authorization. 2 Listed as Endangered under the Endangered Species Act (ESA) 

3Proposed take is adjusted according to group size in table 13. 

4Proposed take is rounded to the nearest whole number. 

5Two stocks of common bottlenose dolphin (the western North Atlantic migratory coastal stock and the western North Atlantic offshore stock) 

may occur in the Project area. Both stocks are presented together here. 6Exposure estimates include harbor seals, gray seals, and harp seals combined. 

7 During the MarWin campaign in year 1, US Wind plans to install 21 11-m monopiles and 4 3-m pin piles. 

8 During the Momentum Wind campaign in year 2, US Wind plans to install 55 11-m monopiles, 8 3-m pin piles, and 3 1.8-m pin piles. 9 During the Future Development campaign in year 3, US Wind plans to install 38 11-m monopiles and 4 3-m pin piles. 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 549 

TABLE 19—MODELED LEVEL B HARASSMENT EXPOSURES (ASSUMING 10-dB SOUND ATTENUATION) DUE TO IMPACT PILE

DRIVING OF 1.8-m PIN PILES (ASSUME THREE TOTAL PIN PILES FOR THE MET TOWER) IN THE BUFFERED LEASE

AREA DURING YEAR 2 1 2 AND PROPOSED TAKE 8

Marine mammal species 

Level B 

harassment 

acoustic 

exposure 

estimate 

(160 dBrms) 

Level B 

harassment 

proposed take 

estimate 

North Atlantic right whale 3 .......................................................................................................................... 0 0 

Fin whale 3 4 ................................................................................................................................................. 0.01 2 

Humpback whale 4 ....................................................................................................................................... 0.01 2 

Minke whale 5 ............................................................................................................................................... 0.01 1 

Sei whale 3 ................................................................................................................................................... 0 0 

Killer whale .................................................................................................................................................. 0 0 

Atlantic spotted dolphin ............................................................................................................................... 0 0 

Bottlenose dolphin (offshore stock/coastal stock) 5 6 ................................................................................... 1.91 2 

Common dolphin 4 ....................................................................................................................................... 0.18 7 

Long-finned pilot whale ................................................................................................................................ 0 0 

Short-finned pilot whale ............................................................................................................................... 0 0 

Pantropical spotted dolphin ......................................................................................................................... 0 0 

Risso’s dolphin ............................................................................................................................................. 0 0 

Rough toothed dolphin ................................................................................................................................ 0 0 

Striped dolphin ............................................................................................................................................. 0 0 

Harbor porpoise ........................................................................................................................................... 0 0 

Gray seal 7 ................................................................................................................................................... 0.09 0 

Harbor seal 7.

Harp seal 7.

1 In-water construction activities to install the Met tower would take place only during year 2. 

2 Modeled acoustic exposure estimates for all species were zero for take by Level A harassment. Therefore, no take by Level A harassment is 

anticipated or proposed for authorization. 3 Listed as Endangered under the Endangered Species Act (ESA). 

4Proposed take is adjusted according to group size in table 13. 

5Proposed take is rounded to the nearest whole number. 

6Two stocks of common bottlenose dolphin (the western North Atlantic migratory coastal stock and the western North Atlantic offshore stock) 

may occur in the Project area. Both stocks are presented together here. 7Exposure estimates include harbor seals, gray seals, and harp seals. 

8 During the Momentum Wind campaign in year 2, US Wind plans to install 55 11-m monopiles, 8 3-m pin piles, and 3 1.8-m pin piles. 

TABLE 20—PROPOSED TAKES BY LEVEL A HARASSMENT AND LEVEL B HARASSMENT FOR ALL IMPACT PILE DRIVING

ACTIVITIES IN THE BUFFERED LEASE AREA OVER 3 YEARS

Marine mammal species Population 

estimate 

Proposed take by Level A 

harassment 

Proposed take by Level B 

harassment 

Year 1 

(2025) 

Year 2 

(2026) 

Year 3 

(2027) 

Year 1 

(2025) 

Year 2 

(2026) 

Year 3 

(2027) 

North Atlantic right whale 1 ........................................................ 338 0 0 0 2 2 2 

Fin whale 1 2 .............................................................................. 6,802 2 2 2 6 16 9 

Humpback whale 2 .................................................................... 1,396 2 2 2 5 14 7 

Minke whale .............................................................................. 21,968 1 6 2 4 36 8 

Sei whale 1 ................................................................................ 6,292 1 1 1 1 1 1 

Killer whale 3 .............................................................................. UNK 0 0 0 3 3 3 

Atlantic spotted dolphin 4 ........................................................... 39,921 0 0 0 30 60 60 

Bottlenose dolphin (coastal stock) 5 .......................................... 6,639 0 0 0 0 703 1,462 

Bottlenose dolphin (offshore stock) 5 ........................................ 62,851 0 0 0 857 1,639 259 

Common dolphin ....................................................................... 172,974 0 0 0 36 248 104 

Long-finned pilot whale 6 ........................................................... 39,215 0 0 0 11 11 11 

Short-finned pilot whale 6 .......................................................... 28,924 0 0 0 16 16 16 

Pantropical spotted dolphin ....................................................... 6,593 0 0 0 5 5 5 

Risso’s dolphin 7 ........................................................................ 35,215 0 0 0 18 18 18 

Rough toothed dolphin 3 ............................................................ 136 0 0 0 6 6 6 

Striped dolphin 3 ........................................................................ 67,306 0 0 0 46 46 46 

Harbor porpoise 8 ...................................................................... 95,543 0 3 3 3 16 3 

Gray seal 9 ................................................................................. 27,300 0 0 0 18 235 31 

Harbor seal 9 ............................................................................. 61,336 

Harp seal 9 ................................................................................. 7.6M 

1 Listed as Endangered under the Endangered Species Act (ESA). 

2Total proposed take by Level A harassment was increased according to average group size (table 13), rounded to the nearest whole number, for years 1 and 3. 

3Total proposed take by Level B harassment was increased according to average group size for each year of pile driving activities (table 13). It was assumed that 

one group would be encountered per year. 4Total proposed take by Level B harassment was increased according to average group size for each year of pile driving activities. Proposed takes for Atlantic 

spotted dolphins are based upon the assumption that 5 groups of 6 (RPS, 2023) will be observed during year 1 of pile driving activities, and 10 groups of 6 would be 

observed during each of years 2 and 3 pile driving activities. 5Bottlenose dolphin take by Level B harassment was allocated to each stock based upon the direction of the progression of pile driving throughout project years 1– 

3 as follows: year 1 (100 percent offshore stock); year 2 (70 percent offshore stock; 30 percent coastal stock); year 3 (15 percent offshore stock; 85 percent coastal 

stock). 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
550 Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 

6Total pilot whale acoustic exposures were low, and apportioning take as 60 percent short-finned pilot whale and 40 percent long-finned pilot whale resulted in calculated takes of less than one for both species. As these calculated acoustic exposure estimates were less than average group size for both species, requested take 

by Level B harassment was based upon the assumption of one group of each species being encountered during each year of pile driving activities (table 13). 7Total proposed take by Level B harassment was increased according to average group size for each year of pile driving activities. Proposed take by Level B harassment for Risso’s dolphins is based upon the assumption that two groups of nine (DoN, 2017) would be observed during each year of pile driving. 8Total proposed take was increased according to average group size. It is expected that one group of harbor porpoises would be taken by Level A harassment during years 2 and 3 and by Level B harassment in years 1 and 3. Proposed take represents monopile installation only as exposure estimates for pin pile installation 

were zero. 9Total proposed take by Level B harassment for seals includes harbor seals, gray seals, and harp seals. 

HRG Surveys 

US Wind’s proposed HRG survey 

activity includes the use of impulsive 

sources (i.e., boomers, sparkers) that 

have the potential to harass marine 

mammals. The list of equipment 

proposed is in table 4 (see Detailed 

Description of the Specified Activity). 

Authorized takes would be by Level B 

harassment only in the form of 

disruption of behavioral patterns for 

individual marine mammals resulting 

from exposure to noise from certain 

HRG acoustic sources. Based primarily 

on the characteristics of the signals 

produced by the acoustic sources 

planned for use, Level A harassment is 

neither anticipated nor proposed to be 

authorized. Therefore, the potential for 

Level A harassment is not evaluated 

further in this document. US Wind did 

not request, and NMFS is not proposing 

to authorize, take by Level A harassment 

incidental to HRG surveys. No serious 

injury or mortality is anticipated to 

result from HRG survey activities. 

Specific to HRG surveys, in order to 

better consider the narrower and 

directional beams of the sources, NMFS 

has developed a tool, available at 

https://www.fisheries.noaa.gov/ 

national/marine-mammal-protection/ 

marine-mammal-acoustic-technicalguidance, for determining the distances 

at which sound pressure level (SPLrms) 

generated from HRG surveys reach the 

160-dB threshold. The equations in the 

tool consider water depth, frequencydependent absorption, and some 

directionality to refine estimated 

ensonified zones. The isopleth distances 

corresponding to the Level B 

harassment threshold for each type of 

HRG equipment with the potential to 

result in harassment of marine 

mammals were calculated per NOAA 

Fisheries’ Interim Recommendation for 

Sound Source Level and Propagation 

Analysis for High Resolution 

Geophysical Sources. Input for HRG 

equipment specifications are provided 

in table 4. Micro-siting HRG surveys 

could occur throughout the Lease Area, 

therefore, US Wind assumed a 

maximum depth of 42 m (137.8 ft) 

which corresponds to the maximum 

depth of the Lease Area. The distances 

to the 160-dB RMS re 1 mPa isopleth for 

Level B harassment are presented in 

table 21. 

TABLE 21—DISTANCES CORRESPONDING TO THE LEVEL B HARASSMENT THRESHOLD FOR HRG EQUIPMENT 1

HRG survey equipment Equipment type 

Horizontal 

distance (m) 

to Level B 

harassment 

threshold 

Applied Acoustics S Boomer ...................................................... SBP: Boomer .............................................................................. 35.2 

AA Dura Spark 400 tip ............................................................... SBP: Sparker .............................................................................. 200 

1Of note, NMFS has performed a preliminary review of a report submitted by Rand (2023), that includes measurements of the Geo-Marine 

Geo-Source 400 sparker (400 tip, 800 J), and suggests that NMFS is assuming lower source and received levels than appropriate in its assessments of HRG impacts. NMFS has determined that the values in our assessment remain appropriate, based on the model methodology (i.e., 

source level propagated using spherical spreading) here predicting a peak level 3 dB louder than the maximum measured peak levels at the 

closest measurement range in Rand (2023). NMFS will continue reviewing Rand (2023) and other available data relevant to these sources. 

The survey activities that have the 

potential to result in Level B harassment 

(160-dB SPL) include the noise 

produced by Applied Acoustics S 

Boomer or AA Dura Spark sparker (table 

21), of which the Dura Spark sparker 

results in the greatest calculated 

distance to the Level B harassment 

criteria at 200 m (656 ft). US Wind has 

applied the estimated distance of 200 m 

(656 ft) to the 160 dBRMS90 percent re 1 

mPa Level B harassment criteria as the 

basis for determining potential take 

from all HRG sources. All noiseproducing survey equipment is assumed 

to be operated concurrently. One vessel 

will operate at a time during HRG 

surveys. 

The zone of influence (ZOI) is the 

total ensonified area around the sound 

source over a 24-hour period. The 

maximum ZOI was estimated by 

considering the distance of the daily 

vessel track line (111.2 km) and the 

largest distance from the sound source 

to the isopleth for the Level B 

harassment threshold (200 m for the 

Dura Spark sparker). US Wind 

calculated the distance of the daily 

vessel track line by multiplying the 

estimated average speed of the vessel (4 

kn; 2.06 m/s) by a maximum of 15 hours 

per survey per day. The following 

equation was used to calculate the 

maximum ZOI: 

ZOI = (Distance traveled/day * 2r) + r2, 

where 

r is the maximum distance to the Level B 

threshold (200 m) and the maximum ZOI 

was 44.6 km2. 

Exposure calculations assumed that 

there would be 14 days of HRG 

surveying per year during years 2 (2026) 

and 3 (2027). As described in the ITA 

application, density data were mapped 

within the buffered Lease Area using 

geographic information systems, and 

these data were updated based upon the 

revised data from the Duke Model 

(Roberts et al., 2023). Although HRG 

surveys are expected to occur between 

April and June each year, to be 

conservative, the maximum monthly 

average density for each species for an 

entire year was used and carried 

forward in the take calculations (table 

21). Calculations assume a daylight-only 

schedule for HRG surveys. NMFS 

rounded exposure estimates to the 

nearest whole number to generate take 

estimates, except for species for which 

take is not proposed due to mitigation 

measures (table 22). 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 551 

TABLE 22—MARINE MAMMAL DENSITIES (ANIMALS/100 km2), EXPOSURE ESTIMATES, AND PROPOSED TAKES BY LEVEL B 

HARASSMENT FROM HRG SURVEYS DURING YEARS 2 AND 3 1 2

Marine mammal species 

Maximum 

monthly 

density 

(No./km2) 

Year 2 Year 3 

Exposure 

estimate 

Proposed 

take 

Exposure 

estimate 

Proposed 

take 

North Atlantic right whale 3 .................................................. 0.00076 0.5 4 2 0.5 4 2 

Fin whale 3 ........................................................................... 0.214 1.3 4 2 1.3 4 2 

Humpback whale ................................................................. 0.187 1.2 4 02 1.2 4 2 

Minke whale ......................................................................... 0.75 4.7 5 4.7 5 

Sei whale 3 ........................................................................... 0.061 0.4 0 0.4 0 

Killer whale ........................................................................... 0.002 0.01 0 0.01 0 

Atlantic spotted dolphin ........................................................ 1.505 9.4 9 9.4 9 

Bottlenose dolphin 5 ............................................................. 20.608 128.7 129 128.7 129 

Common dolphin .................................................................. 7.939 49.6 50 49.6 50 

Pilot whale species 6 ............................................................ 0.039 0.2 0 0.2 0 

Pantropical spotted dolphin ................................................. 0.004 0.02 0 0.02 0 

Risso’s dolphin ..................................................................... 0.169 1.1 4 8 1.1 4 8 

Rough-toothed dolphin ......................................................... 0.002 0.01 0 0.01 0 

Striped dolphin ..................................................................... 0.004 0.02 0 0.02 0 

Harbor porpoise ................................................................... 3.653 22.8 23 22.8 23 

Gray seal 7 ........................................................................... 16.993 106.1 106 106.1 106 

Harbor seal 7

Harp seal 7

1 Density estimates are calculated from the 2022 Duke Habitat-Based Marine Mammal Density Models (Roberts et al., 2016; Roberts et al., 

2023). Maximum monthly average density for each marine mammal species was used for take calculations. 2The survey area accounts for waters within and around the Lease Area. 

3 Listed as Endangered under the ESA. 

4Proposed take adjusted for group size. See table 13 for average group size estimates. 

5Two stocks of common bottlenose dolphin (the western North Atlantic migratory coastal stock and the western North Atlantic offshore stock) 

may occur in the Project area. Both stocks are presented here. 6 Densities are only available for the combined seal and pilot whale groups in the Roberts et al. (2023) dataset. 7Proposed take by Level B harassment is for harbor seals, gray seals, and harp seals. 

Total Take Across All Activities 

The amount of Level A harassment 

and Level B harassment NMFS proposes 

to authorize incidental to all Project 

activities combined (i.e., pile driving to 

install WTG, OSS, and Met tower 

foundations, and HRG surveys are 

shown in table 24. The annual amount 

of take that is expected to occur in each 

year based on US Wind’s current 

schedules is provided in table 24. The 

year 1 proposed take includes impact 

pile driving of monopiles for WTGs and 

3-m pin piles for the OSSs. Proposed 

take during year 2 includes all activities 

occurring: WTG, OSS, and Met tower 

foundation installation and HRG 

surveys. Year 3 proposed take includes 

WTG and OSS foundation installation 

and HRG surveys. As mentioned above, 

the timing of installation activities and 

HRG surveys would depend upon vessel 

availability, contractor selection, 

weather, and additional factors. 

However, in the event that activities are 

delayed or spread over 4–5 years 

(instead of 3 years), the maximum 

annual amount of take for each species 

would not exceed the numbers listed in 

table 25. 

For each species, if the acoustic 

exposure (for pile driving activities or 

HRG surveys) was less than the average 

group size (table 13), the average group 

size was rounded to the nearest integer 

and used as the proposed take estimate 

by Level A harassment or Level B 

harassment. If the acoustic exposure 

was greater than the average group size 

(table 13), the acoustic exposure was 

rounded to the nearest integer and used 

as the proposed take estimate by Level 

A harassment or Level B harassment. 

For the species for which modeling 

was conducted, the take estimates are 

considered conservative for a number of 

reasons. The amount of take proposed to 

be authorized assumes the most 

impactful scenario with respect to 

project design and schedules. As 

described in the Description of 

Specified Activity section, US Wind 

may use suction-buckets to install OSS 

foundations. Should US Wind use 

suction-bucket foundations, take would 

not occur from OSS foundation 

installation as noise levels would not be 

elevated to the degree there is a 

potential for take (i.e., no pile driving is 

involved with installing suction 

buckets). All calculated take 

incorporated the highest densities for 

any given species in any given month. 

In addition, the amount of proposed 

Level A harassment does not fully 

account for the likelihood that marine 

mammals would avoid a stimulus when 

possible before the individual 

accumulates enough acoustic energy to 

potentially cause auditory injury, or the 

effectiveness of the proposed 

monitoring and mitigation measures 

(with exception of North Atlantic right 

whales given the enhanced mitigation 

measures proposed for this species). 

TABLE 23—PROPOSED TAKES BY LEVEL A HARASSMENT AND LEVEL B HARASSMENT FOR ALL ACTIVITIES PROPOSED TO

BE CONDUCTED ANNUALLY OVER 3 YEARS 1

Marine mammal species 

Year 1 Year 2 Year 3 

Level A 

harassment 

Level B 

harassment 

Level A 

harassment 

Level B 

harassment 

Level A 

harassment 

Level B 

harassment 

North Atlantic right whale 2 3 ............................................ 0 2 0 4 0 4 

Fin whale 2 3 ..................................................................... 2 6 2 18 2 11 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
552 Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 

TABLE 23—PROPOSED TAKES BY LEVEL A HARASSMENT AND LEVEL B HARASSMENT FOR ALL ACTIVITIES PROPOSED TO

BE CONDUCTED ANNUALLY OVER 3 YEARS 1—Continued 

Marine mammal species 

Year 1 Year 2 Year 3 

Level A 

harassment 

Level B 

harassment 

Level A 

harassment 

Level B 

harassment 

Level A 

harassment 

Level B 

harassment 

Humpback whale 3 ........................................................... 2 5 2 16 2 9 

Minke whale 3 ................................................................... 1 4 6 41 2 13 

Sei whale 3 ....................................................................... 1 1 1 1 1 1 

Killer whale 3 .................................................................... 0 3 0 3 0 3 

Atlantic spotted dolphin 3 ................................................. 0 30 0 69 0 69 

Coastal bottlenose dolphin 4 ............................................ 0 0 0 703 0 1,462 

Offshore bottlenose dolphin 4 ........................................... 0 857 0 1,639 0 259 

Bottlenose dolphin 5 ......................................................... 0 0 0 129 0 129 

Common dolphin .............................................................. 0 36 0 298 0 154 

Long-finned pilot whale 3 .................................................. 0 16 0 16 0 16 

Short-finned pilot whale 3 ................................................. 0 11 0 11 0 11 

Pantropical spotted dolphin 3 ........................................... 0 5 0 5 0 5 

Risso’s dolphin ................................................................. 0 18 0 26 0 26 

Rough-toothed dolphin 3 .................................................. 0 6 0 6 0 6 

Striped dolphin 3 ............................................................... 0 46 0 46 0 46 

Harbor porpoise 3 ............................................................. 0 3 3 39 3 26 

Gray seal 6 ....................................................................... 0 18 0 341 0 147 

Harbor seal 6

Harp seal 6

1The final rule and LOA, if issued, would be effective from January 1, 2025 through December 31, 2029. 

2 Listed as Endangered under the ESA. 

3Average group size applied to the proposed take estimate. 

4Proposed take represents take from impact pile driving activities. 

5Proposed take numbers represent requested take from HRG survey activities. Assumes take from the coastal and offshore stock of 

bottlenose dolphins. 6Proposed take includes harbor seals, gray seals, and harp seals. 

TABLE 24—PROPOSED TAKES OF MARINE MAMMALS (BY LEVEL A HARASSMENT AND LEVEL B HARASSMENT) FOR ALL

ACTIVITIES PROPOSED TO BE CONDUCTED DURING THE CONSTRUCTION OF THE PROJECT AND OVER THE COURSE

OF THE RULE

Marine mammal species 

Total proposed 

take by Level A 

harassment 

Total proposed 

take by Level B 

harassment 

North Atlantic right whale 1 2 ................................................................................................................................ 0 10 

Fin whale 1 2 ......................................................................................................................................................... 6 35 

Humpback whale 2 ............................................................................................................................................... 6 30 

Minke whale 2 ....................................................................................................................................................... 9 58 

Sei whale 2 ........................................................................................................................................................... 3 3 

Killer whale 3 ........................................................................................................................................................ 0 9 

Atlantic spotted dolphin 2 ..................................................................................................................................... 0 168 

Coastal bottlenose dolphin 3 ................................................................................................................................ 0 2,165 

Offshore bottlenose dolphin 3 .............................................................................................................................. 0 2,755 

Bottlenose dolphin 4 ............................................................................................................................................. 0 258 

Common dolphin .................................................................................................................................................. 0 488 

Long-finned pilot whale 2 ..................................................................................................................................... 0 48 

Short-finned pilot whale 2 ..................................................................................................................................... 0 33 

Pantropical spotted dolphin 2 ............................................................................................................................... 0 15 

Risso’s dolphin ..................................................................................................................................................... 0 70 

Rough-toothed dolphin 3 ...................................................................................................................................... 0 18 

Striped dolphin 3 ................................................................................................................................................... 0 138 

Harbor porpoise 2 ................................................................................................................................................. 6 68 

Gray seal 5 ........................................................................................................................................................... 0 496 

Harbor seal.5

Harp seal.5

1The final rule and LOA, if issued, would be effective from January 1, 2025 through December 31, 2029. 

2 Listed as Endangered under the ESA. 

3Total 3-year proposed take by Level B harassment includes impact pile driving activities only. 

4Total 3-year proposed take by Level B harassment includes HRG survey activities for both stocks combined. 

5Proposed take includes harbor seals, gray seals, and harp seals. 

To inform both the negligible impact 

analysis and the small numbers 

determination, NMFS assesses the 

maximum number of takes of marine 

mammals that could occur within any 

given year. In this calculation, the 

maximum estimated number of Level A 

harassment takes in any one year is 

summed with the maximum estimated 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 553 

number of Level B harassment takes in 

any one year for each species to yield 

the highest number of estimated take 

that could occur in any year (table 25). 

Table 25 also depicts the number of 

takes proposed relative to the 

abundance of each stock. The takes 

enumerated here represent daily 

instances of take, not necessarily 

individual marine mammals taken. One 

take represents a day in which an 

animal was exposed to noise above the 

associated harassment threshold at least 

once. Some takes represent a brief 

exposure above a threshold, while in 

some cases takes could represent a 

longer, or repeated, exposure of one 

individual animal above a threshold 

within a 24-hour period. Whether or not 

every take assigned to a species 

represents a different individual 

depends on the daily and seasonal 

movement patterns of the species in the 

area. For example, activity areas with 

continuous activities (all or nearly every 

day) overlapping known feeding areas 

(where animals are known to remain for 

days or weeks on end) or areas where 

species with small home ranges live 

(e.g., some pinnipeds) are more likely to 

result in repeated takes to some 

individuals. Alternatively, activities that 

are not occurring on consecutive days 

for the duration of the project (e.g., 

foundation installation) or occurring in 

an area where animals are migratory and 

not expected to remain for multiple 

days, represent circumstances where 

repeat takes of the same individuals are 

less likely. For example, 100 takes could 

represent 100 individuals each taken on 

one day within the year, or it could 

represent 5 individuals each taken on 20 

days within the year. The combination 

of number of individuals each taken and 

number of days on which take would 

occur would depend upon the activity, 

the presence of biologically important 

areas in the project area, and the 

movement patterns of the marine 

mammal species exposed. Where 

information to better contextualize the 

enumerated takes for a given species is 

available, it is discussed in the 

Negligible Impact Analysis and 

Determination and/or Small Numbers 

sections, as appropriate. 

TABLE 25—MAXIMUM NUMBER OF PROPOSED TAKES (BY LEVEL A HARASSMENT AND LEVEL B HARASSMENT) THAT

COULD OCCUR IN ANY ONE YEAR OF THE PROJECT RELATIVE TO STOCK POPULATION SIZE 1

Marine mammal species NMFS stock 

abundance 

Maximum 

annual 

Level A 

harassment 

Maximum 

annual 

Level B 

harassment 

Maximum 

annual take 

Maximum 

proposed take 

(instances) 

as a percentage 

of stock 

abundance) 1 2

North Atlantic right whale 3 4 .......................................................... 338 0 4 4 1.18 

Fin whale 3 4 ................................................................................... 6,802 2 18 20 0.29 

Humpback whale 4 ......................................................................... 1,396 2 16 18 1.29 

Minke whale ................................................................................... 21,968 6 41 47 0.21 

Sei whale 3 4 ................................................................................... 6,292 1 1 2 0.03 

Killer whale 4 .................................................................................. UNK 0 3 3 UNK 

Atlantic spotted dolphin 4 ............................................................... 39,921 0 69 69 0.17 

Coastal bottlenose dolphin 5 .......................................................... 6,639 0 1,591 1,591 24.0 

Offshore bottlenose dolphin 5 ......................................................... 62,851 0 1,768 1,768 2.81 

Common dolphin ............................................................................ 172,974 0 298 298 0.17 

Long-finned pilot whale 4 ................................................................ 39,215 0 16 16 0.04 

Short-finned pilot whale 4 ............................................................... 28,924 0 11 11 0.04 

Pantropical spotted dolphin 4 ......................................................... 6,593 0 5 5 0.08 

Risso’s dolphin 4 ............................................................................. 35,215 0 26 26 0.07 

Rough-toothed dolphin 4 ................................................................ 136 0 6 6 4.41 

Striped dolphin 4 ............................................................................. 67,036 0 46 46 0.07 

Harbor porpoise 4 ........................................................................... 95,543 3 39 42 0.04 

Gray seal 6 ..................................................................................... 27,300 0 341 341 1.25 

Harbor seal 6 .................................................................................. 61,336 0.56 

Harp seal 6 ..................................................................................... 7.6M 0.0004 

1Year 2 (2026) represents the most impactful year overall. 

2The values in this column represent the assumption that each take proposed to be authorized would occur to a unique individual. Given the 

scope of work proposed, this is highly unlikely for species common to the project area (e.g., North Atlantic right whales, humpback whales) such 

that the actual percentage of the population taken is less than the percentages identified here. 3 Listed as Endangered under the ESA. 

4Proposed take is based on average group size. 

5 Maximum proposed take for each bottlenose dolphin species includes the maximum proposed take by Level B harassment of any year for 

HRG surveys. 6Assumes 100 percent of the take by Level B harassment is from either the gray seal stock, harbor seal stock, or harp seal stock. 

Proposed Mitigation 

In order to promulgate a rulemaking 

under section 101(a)(5)(A) of the 

MMPA, NMFS must set forth the 

permissible methods of taking pursuant 

to the activity, and other means of 

effecting the least practicable adverse 

impact on the species or stock and its 

habitat, paying particular attention to 

rookeries, mating grounds, and areas of 

similar significance, and on the 

availability of the species or stock for 

taking for certain subsistence uses (latter 

not applicable for this action). NMFS’ 

regulations require applicants for 

incidental take authorizations to include 

information about the availability and 

feasibility (economic and technological) 

of equipment, methods, and manner of 

conducting the activity or other means 

of effecting the least practicable adverse 

impact upon the affected species or 

stocks and their habitat (50 CFR 

216.104(a)(11)). 

In evaluating how mitigation may or 

may not be appropriate to ensure the 

least practicable adverse impact on 

species or stocks and their habitat, as 

well as subsistence uses where 

applicable, we carefully consider two 

primary factors: 

(1) The manner in which, and the 

degree to which, the successful 

implementation of the measure(s) is 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
554 Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 

expected to reduce impacts to marine 

mammals, marine mammal species or 

stocks, and their habitat. This considers 

the nature of the potential adverse 

impact being mitigated (likelihood, 

scope, range). It further considers the 

likelihood that the measure will be 

effective if implemented (probability of 

accomplishing the mitigating result if 

implemented as planned), the 

likelihood of effective implementation 

(probability implemented as planned); 

and, 

(2) The practicability of the measures 

for applicant implementation, which 

may consider such things as cost, 

impact on operations, and, in the case 

of a military readiness activity, 

personnel safety, practicality of 

implementation, and impact on the 

effectiveness of the military readiness 

activity. 

The mitigation strategies described 

below are consistent with those required 

and successfully implemented under 

previous incidental take authorizations 

issued in association with in-water 

construction activities (e.g., soft-start, 

establishing shutdown zones). 

Additional measures have also been 

incorporated to account for the fact that 

the proposed construction activities 

would occur offshore. Modeling was 

performed to estimate harassment 

zones, which were used to inform 

mitigation measures for the Project’s 

activities to minimize Level A 

harassment and Level B harassment to 

the extent practicable, while providing 

estimates of the areas within which 

Level B harassment might occur. 

Generally speaking, the mitigation 

measures considered and proposed to be 

required here fall into three categories: 

temporal (seasonal and daily) work 

restrictions, real-time measures 

(shutdown, clearance, and vessel strike 

avoidance), and noise attenuation/ 

reduction measures. Seasonal work 

restrictions are designed to avoid or 

minimize operations when marine 

mammals are concentrated or engaged 

in behaviors that make them more 

susceptible or make impacts more 

likely, in order to reduce both the 

number and severity of potential takes 

and are effective in reducing both 

chronic (longer-term) and acute effects. 

Real-time measures, such as 

implementation of shutdown and 

clearance zones, as well as vessel strike 

avoidance measures, are intended to 

reduce the probability or severity of 

harassment by taking steps in real time 

once a higher-risk scenario is identified 

(e.g., once animals are detected within 

an impact zone). Noise attenuation 

measures, such as bubble curtains, are 

intended to reduce the noise at the 

source, which reduces both acute 

impacts, as well as the contribution to 

aggregate and cumulative noise that may 

result in longer-term chronic impacts. 

Below, we briefly describe the 

required training, coordination, and 

vessel strike avoidance measures that 

apply to all activity types, and then in 

the following subsections we describe 

the measures that apply specifically to 

foundation installation, nearshore 

installation and removal activities for 

cable laying, and HRG surveys. Details 

on specific requirements can be found 

in Part 217—Regulations Governing The 

Taking And Importing Of Marine 

Mammals at the end of this proposed 

rulemaking. 

Training and Coordination 

NMFS requires all US Wind’s 

employees and contractors conducting 

activities on the water, including, but 

not limited to, all vessel captains and 

crew, to be trained in marine mammal 

detection and identification, 

communication protocols, and all 

required measures to minimize impacts 

on marine mammals and support US 

Wind’s compliance with the LOA, if 

issued. Additionally, all relevant 

personnel and the marine mammal 

species monitoring team(s) are required 

to participate in joint, onboard briefings 

prior to the beginning of project 

activities. The briefing must be repeated 

whenever new relevant personnel (e.g., 

new PSOs, construction contractors, 

relevant crew) join the project before 

work commences. During this training, 

US Wind is required to instruct all 

project personnel regarding the 

authority of the marine mammal 

monitoring team(s). For example, the 

HRG acoustic equipment operator, pile 

driving personnel, etc., are required to 

immediately comply with any call for a 

delay or shut down by the Lead PSO. 

Any disagreement between the Lead 

PSO and the project personnel must 

only be discussed after delay or 

shutdown has occurred. In particular, 

all captains and vessel crew must be 

trained in marine mammal detection 

and vessel strike avoidance measures to 

ensure marine mammals are not struck 

by any project or project-related vessel. 

Prior to the start of in-water 

construction activities, vessel operators 

and crews would receive training about 

marine mammals and other protected 

species known or with the potential to 

occur in the Project Area, making 

observations in all weather conditions, 

and vessel strike avoidance measures. In 

addition, training would include 

information and resources available 

regarding applicable Federal laws and 

regulations for protected species. US 

Wind will provide documentation of 

training to NMFS. 

North Atlantic Right Whale Awareness 

Monitoring 

US Wind would be required to use 

available sources of information on 

North Atlantic right whale presence, 

including daily monitoring of the Right 

Whale Sightings Advisory System, 

monitoring of U.S. Coast Guard very 

high-frequency (VHF) Channel 16 

throughout each day to receive 

notifications of any sightings, and 

information associated with any 

regulatory management actions (e.g., 

establishment of a zone identifying the 

need to reduce vessel speeds). 

Maintaining daily awareness and 

coordination affords increased 

protection of North Atlantic right 

whales by understanding North Atlantic 

right whale presence in the area through 

ongoing visual and passive acoustic 

monitoring efforts and opportunities 

(outside of US Wind’s efforts), and 

allows for planning of construction 

activities, when practicable, to 

minimize potential impacts on North 

Atlantic right whales. 

Vessel Strike Avoidance Measures 

This proposed rule contains 

numerous vessel strike avoidance 

measures that reduce the risk that a 

vessel and marine mammal could 

collide. While the likelihood of a vessel 

strike is generally low, they are one of 

the most common ways that marine 

mammals are seriously injured or killed 

by human activities. Therefore, 

enhanced mitigation and monitoring 

measures are required to avoid vessel 

strikes, to the extent practicable. While 

many of these measures are proactive, 

intending to avoid the heavy use of 

vessels during times when marine 

mammals of particular concern may be 

in the area, several are reactive and 

occur when a project personnel sights a 

marine mammal. The mitigation 

requirements we propose are described 

generally here and in detail in the 

regulation text at the end of this 

proposed rule (see 50 CFR 217.264(b)). 

US Wind would be required to comply 

with these measures except under 

circumstances when doing so would 

create an imminent and serious threat to 

a person or vessel or to the extent that 

a vessel is unable to maneuver and, 

because of the inability to maneuver, the 

vessel cannot comply. 

While underway, US Wind’s 

personnel would be required to monitor 

for and maintain a minimum separation 

distance from marine mammals and 

operate vessels in a manner that reduces 

the potential for vessel strike. 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 555 

Regardless of the vessel’s size, all vessel 

operators, crews, and dedicated visual 

observers (i.e., PSO or trained crew 

member) must maintain a vigilant watch 

for all marine mammals and slow down, 

stop their vessel, or alter course (as 

appropriate) to avoid striking any 

marine mammal. The dedicated visual 

observer, equipped with suitable 

monitoring technology (e.g., binoculars, 

night vision devices), must be located at 

an appropriate vantage point for 

ensuring vessels are maintaining 

required vessel separation distances 

from marine mammals (e.g., 500 m from 

North Atlantic right whales). 

All project vessels, regardless of size, 

must maintain the following minimum 

separation zones: 500 m from North 

Atlantic right whales; 100 m from sperm 

whales and non-North Atlantic right 

whale baleen whales; and 50 m from all 

delphinid cetaceans and pinnipeds (an 

exception is made for those species that 

approach the vessel such as bow-riding 

dolphins) (table 26). All reasonable 

steps must be taken to not violate 

minimum separation distances. If any of 

these species are sighted within their 

respective minimum separation zone, 

the underway vessel must shift its 

engine to neutral (if safe to do so) and 

the engines must not be engaged until 

the animal(s) have been observed to be 

outside of the vessel’s path and beyond 

the respective minimum separation 

zone. If a North Atlantic right whale is 

observed at any distance by any project 

personnel or acoustically detected, 

project vessels must reduce speeds to 10 

kn. Additionally, in the event that any 

project-related vessel, regardless of size, 

observes any large whale (other than a 

North Atlantic right whale) within 500 

m of an underway vessel, the vessel is 

required to immediately reduce speeds 

to 10 kn or less. The 10 kn speed 

restriction will remain in effect as 

outlined in 50 CFR 217.344(b). 

TABLE 26—HRG VESSEL STRIKE AVOIDANCE SEPARATION ZONES

Marine mammal species Vessel separation zone 

(m) 

North Atlantic right whale .................................................................................................................................................... 500 

Other ESA-listed species and large whales ........................................................................................................................ 100 

Other marine mammals 1 ..................................................................................................................................................... 50 

1With the exception of seals and delphinid(s) from the genera Delphinus, Lagenorhynchus, Stenella or Tursiops, as described below. 

All of the project-related vessels 

would be required to comply with 

existing NMFS vessel speed restrictions 

for North Atlantic right whales and the 

measures within this rulemaking for 

operating vessels around North Atlantic 

right whales and other marine 

mammals. When NMFS vessel speed 

restrictions are not in effect and a vessel 

is traveling at greater than 10 kn, in 

addition to the required dedicated 

visual observer, US Wind would be 

required to monitor the crew transfer 

vessel transit corridor (the path crew 

transfer vessels take from port to any 

work area) in real-time with PAM prior 

to and during transits. To maintain 

awareness of North Atlantic right whale 

presence, vessel operators, crew 

members, and the marine mammal 

monitoring team will monitor U.S. Coast 

Guard VHF Channel 16, WhaleAlert, the 

Right Whale Sighting Advisory System 

(RWSAS), and the PAM system. Any 

marine mammal observed by project 

personnel must be immediately 

communicated to any on-duty PSOs, 

PAM operator(s), and all vessel 

captains. Any North Atlantic right 

whale or large whale observation or 

acoustic detection by PSOs or PAM 

operators must be conveyed to all vessel 

captains. All vessels would be equipped 

with an AIS and US Wind must report 

all Maritime Mobile Service Identity 

(MMSI) numbers to NMFS Office of 

Protected Resources prior to initiating 

in-water activities. US Wind will submit 

a NMFS-approved North Atlantic Right 

Whale Vessel Strike Avoidance Plan at 

least 90 days prior to commencement of 

vessel use. 

US Wind’s compliance with these 

proposed measures would reduce the 

likelihood of vessel strike to the extent 

practicable. These measures increase 

awareness of marine mammals in the 

vicinity of project vessels and require 

project vessels to reduce speed when 

marine mammals are detected (by PSOs, 

PAM, and/or through another source, 

e.g., RWSAS) and maintain separation 

distances when marine mammals are 

encountered. While visual monitoring is 

useful, reducing vessel speed is one of 

the most effective, feasible options 

available to reduce the likelihood of and 

effects from a vessel strike. Numerous 

studies have indicated that slowing the 

speed of vessels reduces the risk of 

lethal vessel collisions, particularly in 

areas where right whales are abundant 

and vessel traffic is common and 

otherwise traveling at high speeds 

(Vanderlaan and Taggart, 2007; Conn 

and Silber, 2013; Van der Hoop et al., 

2014; Martin et al., 2015; Crum et al., 

2019). 

Seasonal and Daily Restrictions 

Temporal restrictions in places where 

marine mammals are concentrated, 

engaged in biologically important 

behaviors, and/or present in sensitive 

life stages are effective measures for 

reducing the magnitude and severity of 

human impacts. The temporal 

restrictions required here are built 

around North Atlantic right whale 

protection. Based upon the best 

scientific information available (Roberts 

et al., 2023), the highest densities of 

North Atlantic right whales in the 

specified geographic region are expected 

during the months of January through 

April, with an increase in density 

starting in December. However, North 

Atlantic right whales may be present in 

the specified geographic region 

throughout the year. 

NMFS is proposing to require 

seasonal work restrictions to minimize 

risk of noise exposure to the North 

Atlantic right whales incidental to 

certain specified activities to the extent 

practicable. These seasonal work 

restrictions are expected to greatly 

reduce the number of takes of North 

Atlantic right whales. These seasonal 

restrictions also afford protection to 

other marine mammals that are known 

to use the Project Area with greater 

frequency during winter months, 

including other baleen whales. 

As described previously, no impact 

pile driving activities may occur 

December 1 through April 30. NMFS is 

not proposing any seasonal restrictions 

to HRG surveys; however, US Wind has 

planned a limited amount of surveys 

(over 14 days) during daylight within 

the proposed effective period of these 

regulations. 

NMFS is also proposing temporal 

restrictions for some activities. Within 

any 24-hour period, NMFS proposes to 

limit installing up to one monopile 

foundation or four 3-m pin piles during 

daylight hours only unless US Wind 

requests to install additional piles per 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
556 Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 

day in order to complete construction 

more quickly, provided the modeling 

information necessary to adaptively 

manage mitigation zone sizes as well as 

information identifying the change to 

the pile driving schedule would not 

result in more take (annual or 5-year 

total) than analyzed in the final rule or 

authorized in any associated LOA, and 

such request is approved by NMFS. US 

Wind does not plan to initiate pile 

driving later than 1.5 hours after civil 

sunset or continue pile driving after or1 

hour before civil sunrise. However, if 

US Wind determines that they may 

initiate pile driving after the 

aforementioned time frame, they must 

submit a sufficient nighttime pile 

driving plan for NMFS review and 

approval to do so. A sufficient nighttime 

pile driving plan would demonstrate 

that proposed detection systems would 

be capable of detecting marine 

mammals, particularly large whales, at 

distances necessary to ensure mitigation 

measures are effective. US Wind would 

also be encouraged to investigate and 

test advanced technology to support 

their request. NMFS proposes to 

condition the LOA such that nighttime 

pile driving would only be allowed if 

US Wind submitted an Alternative 

Monitoring Plan to NMFS for approval 

that proved the efficacy of their night 

vision devices (e.g., mounted thermal/ 

infrared (IR) camera systems, hand-held 

or wearable night vision devices 

(NVDs), IR spotlights) in detecting 

protected marine mammals. If the plan 

did not include a full description of the 

proposed technology, monitoring 

methodology, and data supporting that 

marine mammals could reliably and 

effectively be detected within the 

clearance and shutdown zones for 

monopiles and pin piles before and 

during impact pile driving, nighttime 

pile driving (unless a pile was initiated 

1.5 hours prior to civil sunset) would 

not be allowed. The Plan should 

identify the efficacy of the technology at 

detecting marine mammals in the 

clearance and shutdown zones under all 

of the various conditions anticipated 

during construction, including varying 

weather conditions, sea states, and in 

consideration of the use of artificial 

lighting. Given the very small Level B 

harassment zone associated with HRG 

survey activities and no anticipated or 

authorized Level A harassment, NMFS 

is not proposing any daily restrictions 

for HRG surveys. 

More information on activity-specific 

seasonal and daily restrictions can be 

found in the regulatory text at the end 

of this proposed rulemaking. 

Noise Attenuation Systems 

US Wind would be required to 

employ noise abatement systems (NAS), 

also known as noise attenuation 

systems, during all foundation 

installation (i.e., impact pile driving) 

activities to reduce the sound pressure 

levels that are transmitted through the 

water in an effort to reduce acoustic 

ranges to the Level A harassment and 

Level B harassment acoustic thresholds 

and minimize, to the extent practicable, 

any acoustic impacts resulting from 

these activities. US Wind would be 

required to use at least two NAS to 

ensure that measured sound levels do 

not exceed the levels modeled for a 10- 

dB sound level reduction for foundation 

installation, which is likely to include a 

double big bubble curtain combined 

with another NAS (other available NAS 

technologies are the hydro-sound 

damper, or an AdBm Helmholz 

resonator), as well as the adjustment of 

operational protocols to minimize noise 

levels. A single bubble curtain, alone or 

in combination with another NAS 

device, may not be used for pile driving 

as received SFV data reveals this 

approach is unlikely to attenuate sound 

sufficiently to be consistent with the 

modeling underlying our take analysis 

here, which incorporates expected 

ranges to the Level A and Level B 

harassment isopleths assuming 10 dB of 

attenuation and appropriate NAS use. 

Should the research and development 

phase of newer systems demonstrate 

effectiveness, as part of adaptive 

management, US Wind may submit data 

on the effectiveness of these systems 

and request approval from NMFS to use 

them during foundation installation 

activities. 

Two categories of NAS exist: primary 

and secondary. A primary NAS would 

be used to reduce the level of noise 

produced by foundation installation 

activities at the source, typically 

through adjustments to the equipment 

(e.g., hammer strike parameters). 

Primary NAS are still evolving and will 

be considered for use during mitigation 

efforts when the NAS has been 

demonstrated as effective in commercial 

projects. However, as primary NAS are 

not fully effective at eliminating noise, 

a secondary NAS would be employed. 

The secondary NAS is a device or group 

of devices that would reduce noise as it 

was transmitted through the water away 

from the pile, typically through a 

physical barrier that would reflect or 

absorb sound waves and, therefore, 

reduce the distance the higher energy 

sound propagates through the water 

column. Together, these systems must 

reduce noise levels to those not 

exceeding modeled ranges to Level A 

harassment and Level B harassment 

isopleths corresponding to those 

modeled assuming 10-dB sound 

attenuation, pending results of SFV (see 

Sound Field Verification section below 

and Part 217—Regulations Governing 

The Taking And Importing Of Marine 

Mammals). 

Noise abatement systems, such as 

bubble curtains, are used to decrease the 

sound levels radiated from a source. 

Bubbles create a local impedance 

change that acts as a barrier to sound 

transmission. The size of the bubbles 

determines their effective frequency 

band, with larger bubbles needed for 

lower frequencies. There are a variety of 

bubble curtain systems, confined or 

unconfined bubbles, and some with 

encapsulated bubbles or panels. 

Attenuation levels also vary by type of 

system, frequency band, and location. 

Small bubble curtains have been 

measured to reduce sound levels, but 

effective attenuation is highly 

dependent on depth of water, current, 

and configuration and operation of the 

curtain (Austin et al., 2016; Koschinski 

and Lu ̈demann, 2013). Bubble curtains 

vary in terms of the sizes of the bubbles 

and those with larger bubbles tend to 

perform a bit better and more reliably, 

particularly when deployed with two 

separate rings (Bellmann, 2014; 

Koschinski and Lu ̈demann, 2013; Nehls 

et al., 2016). Encapsulated bubble 

systems (i.e., Hydro Sound Dampers 

(HSDs)), can be effective within their 

targeted frequency ranges (e.g., 100–800 

Hz), and when used in conjunction with 

a bubble curtain appear to create the 

greatest attenuation. The literature 

presents a wide array of observed 

attenuation results for bubble curtains. 

The variability in attenuation levels is 

the result of variation in design as well 

as differences in site conditions and 

difficulty in properly installing and 

operating in-water attenuation devices. 

For example, Da ̈hne et al. (2017) 

found that single bubble curtains that 

reduce sound levels by 7 to 10 dB 

reduced the overall sound level by 

approximately 12 dB when combined as 

a double bubble curtain for 6-m steel 

monopiles in the North Sea. During 

installation of monopiles (consisting of 

approximately 8-m in diameter) for 

more than 150 WTGs in comparable 

water depths (>25 m) and conditions in 

Europe indicate that attenuation of 10 

dB is readily achieved (Bellmann, 2019; 

Bellmann et al., 2020) using single big 

bubble curtains (BBCs) for noise 

attenuation. When a double big bubble 

curtain is used (noting a single bubble 

curtain is not allowed), US Wind would 

be required to maintain numerous 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 557 

operational performance standards. 

These standards are defined in the 

regulatory text at the end of this 

proposed rulemaking and include but 

are not limited to construction 

contractors must train personnel in the 

proposed balancing of airflow to the 

bubble ring and US Wind would be 

required to submit a performance test 

and maintenance report to NMFS within 

72 hours following the performance test. 

Corrections to the attenuation device to 

meet regulatory requirements must 

occur prior to use during foundation 

installation activities. In addition, a full 

maintenance check (e.g., manually 

clearing holes) must occur prior to each 

pile being installed. If US Wind uses a 

noise mitigation device in addition to a 

double big bubble curtain, similar 

quality control measures are required. 

US Wind would be required to 

conduct SFV and submit an SFV plan to 

NMFS for approval at least 180 days 

prior to installing foundations. They 

would also be required to submit 

interim and final SFV data results to 

NMFS and make corrections to the noise 

attenuation systems in the case that any 

SFV measurements demonstrate noise 

levels are above those modeled 

assuming 10 dB of attenuation. These 

frequent and immediate reports would 

allow NMFS to better understand the 

sound fields to which marine mammals 

are being exposed and require 

immediate corrective action should they 

be misaligned with anticipated noise 

levels within our analysis. 

Noise abatement devices are not 

required during HRG surveys. NAS 

cannot practicably be employed around 

a moving survey ship, but US Wind 

would be required to make efforts to 

minimize source levels by using the 

lowest energy settings on equipment 

that has the potential to result in 

harassment of marine mammals (e.g., 

sparkers, boomers) and turn off 

equipment when not actively surveying. 

Overall, minimizing the amount and 

duration of noise in the ocean from any 

of the project’s activities through use of 

all means necessary (e.g., noise 

abatement, turning off power) will effect 

the least practicable adverse impact on 

marine mammals. 

Clearance and Shutdown Zones 

NMFS is proposing to require the 

establishment of both clearance and 

shutdown zones during project 

activities that have the potential to 

result in harassment of marine 

mammals. The purpose of ‘‘clearance’’ 

of a particular zone is to minimize 

potential instances of auditory injury 

and more severe behavioral 

disturbances by delaying the 

commencement of an activity if marine 

mammals are near the activity. The 

purpose of a shutdown is to prevent a 

specific acute impact, such as auditory 

injury or severe behavioral disturbance 

of sensitive species, by halting the 

activity. 

All relevant clearance and shutdown 

zones during project activities would be 

monitored by NMFS-approved PSOs 

and/or PAM operators (as described in 

the regulatory text at the end of this 

proposed rulemaking). At least one 

PAM operator must review data from at 

least 24 hours prior to foundation 

installation and actively monitor 

hydrophones for 60 minutes prior to 

commencement of these activities. Any 

sighting or acoustic detection of a North 

Atlantic right whale triggers a delay to 

commencing pile driving and 

shutdown. 

Prior to the start of certain specified 

activities (foundation installation and 

HRG surveys), US Wind would be 

required to ensure designated areas (i.e., 

clearance zones, tables 26, 27, and 28) 

are clear of marine mammals prior to 

commencing activities to minimize the 

potential for and degree of harassment. 

For foundation installation, PSOs must 

visually monitor clearance zones for 

marine mammals for a minimum of 60 

minutes, where the zone must be 

confirmed free of marine mammals at 

least 30 minutes directly prior to 

commencing these activities. For 

monopile foundation installation, the 

minimum visibility zone, defined as the 

area over which PSOs must be able to 

visually detect marine mammals, would 

extend 2,900 m (9,514 ft) for monopile 

installation, 1,400 m for 3-m pin pile 

installation, and 200 m for 1.8-m pin 

pile installation (table 26). Clearance 

zones are defined and provided in table 

26 for all species. 

For any other in-water construction 

heavy machinery activities (e.g., 

trenching, cable laying, etc.), if a marine 

mammal is on a path towards or comes 

within 10 m (32.8 ft) of equipment, US 

Wind would be required to cease 

operations until the marine mammal has 

moved more than 10 m on a path away 

from the activity to avoid direct 

interaction with equipment. 

Once an activity begins, any marine 

mammal entering their respective 

shutdown zone would trigger the 

activity to cease. In the case of pile 

driving, the shutdown requirement may 

be waived if is not practicable due to 

imminent risk of injury or loss of life to 

an individual or risk of damage to a 

vessel that creates risk of injury or loss 

of life for individuals, or if the lead 

engineer determines there is pile refusal 

or pile instability. 

In situations when shutdown is called 

for, but US Wind determines shutdown 

is not practicable due to aforementioned 

emergency reasons, reduced hammer 

energy must be implemented when the 

lead engineer determines it is 

practicable. Specifically, pile refusal or 

pile instability could result in not being 

able to shut down pile driving 

immediately. Pile refusal occurs when 

the pile driving sensors indicate the pile 

is approaching refusal, and a shut-down 

would lead to a stuck pile which then 

poses an imminent risk of injury or loss 

of life to an individual, or risk of 

damage to a vessel that creates risk for 

individuals. Pile instability occurs when 

the pile is unstable and unable to stay 

standing if the piling vessel were to ‘‘let 

go.’’ During these periods of instability, 

the lead engineer may determine a shutdown is not feasible because the shutdown combined with impending 

weather conditions may require the 

piling vessel to ‘‘let go’’ which then 

poses an imminent risk of injury or loss 

of life to an individual, or risk of 

damage to a vessel that creates risk for 

individuals. US Wind must document 

and report to NMFS all cases where the 

emergency exemption is taken. 

After shutdown, impact pile driving 

may be reinitiated once all clearance 

zones are clear of marine mammals for 

the minimum species-specific periods, 

or, if required to maintain pile stability, 

impact pile driving may be reinitiated 

but must be used to maintain stability. 

If pile driving has been shut down due 

to the presence of a North Atlantic right 

whale, pile driving must not restart 

until the North Atlantic right whale has 

not been visually or acoustically 

detected for 30 minutes. Upon restarting pile driving, soft-start protocols 

must be followed if pile driving has 

ceased for 30 minutes or longer. 

The clearance and shutdown zone 

sizes vary by species and are shown in 

tables 27 and 28. US Wind would be 

allowed to request modification to these 

zone sizes pending results of sound 

field verification (see regulatory text at 

the end of this proposed rulemaking). 

Any changes to zone size would be part 

of adaptive management and would 

require NMFS’ approval. 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
558 Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 

TABLE 27—MINIMUM VISIBILITY, CLEARANCE, SHUTDOWN, AND LEVEL B HARASSMENT ZONES DURING IMPACT PILE

DRIVING, ASSUMING 10 dB OF ATTENUATION

Monitoring zone North Atlantic 

right whales Other large whales Delphinids and pilot whales Harbor porpoises Seals 

Minimum Visibility Zone 1 Monopiles: 2,900 m. 

3-m pin piles: 1,400 m. 

1.8-m pin piles: 200 m. 

Clearance Zone ............... Any distance (visual) or Monopiles: 5,250 m ........ Monopiles: 500 m. 

within PAM Monitoring 3-m pin piles: 1,400 m ... 3-m pin piles: 200 m. 

Zone. 1.8-m Pin piles: 200 m 2. 1.8 m pin piles: 200 m 3. 

Shutdown Zone ............... Any distance (visual) or Monopiles: 2,900 m ........ Monopiles: 250 m. 

within PAM Monitoring 3-m pin piles: 1,400 m ... 3-m pin piles, 1.8-m pin piles: 100 m 5. 

Zone. 1.8-m Pin piles: 100 m 4. 

PAM Monitoring Zone 6 ... 10,000 m 

Level B Harassment Monopiles: 5,250 m. 

(Acoustic Range, R95%) 3-m pin piles: 500 m. 

1.8-m pin piles: 100 m. 

1The minimum visibility zone is equal to the modeled maximum R95 percent distances to the Level A harassment threshold for low-frequency cetaceans for 

monopiles and 3-m pin piles. The minimum visibility zone for 1.8-m pin piles is equal to the clearance zone, which is double the modeled maximum R95 percent distance to the Level B harassment threshold (100 m) and four times the modeled maximum R95 percent distance to the Level A harassment threshold (50 m) for low-frequency cetaceans. NMFS increased the 1.8-m pin pile minimum visibility zone given the very small zone sizes from this short (3 piles total) activity. 2The clearance zone for other large whales from monopile installation is equal to the modeled maximum R95 percent distance to the Level B harassment threshold 

(5,250 m). The clearance zone for other large whales from 3-m pin pile installation is equal to the modeled maximum R95 percent distance to the Level A harassment 

threshold (1,400 m), given the Level B harassment zone (500 m) is less than this distance. The clearance zone for other large whales from 1.8-m pin pile installation 

is equal to twice the modeled maximum R95 percent distance to the Level B harassment threshold given the very small Level B harassment zone (100 m), which could 

be encompassed by the bubble curtains. 3The clearance zone for non-large whales (i.e., delphinids and pilot whales, harbor porpoises, and seals) from monopile and 3-m pin pile installation is equal to 

double the modeled maximum R95 percent distances to the Level A harassment threshold for harbor porpoise (the most sensitive species). The clearance zone for 1.8- 

m pin pile installation is equal to double the modeled maximum R95 percent distance to the Level B harassment threshold given Level A harassment thresholds were 

not exceeded for this activity (i.e., 0 m). US Wind requested the clearance zone for non-large whales be identical for PSO implementation ease. 4The shutdown zones for other large whales from monopiles and 3-m pin piles are equal to the modeled maximum R95 percent distances to the Level A harassment 

threshold for low-frequency cetaceans. The shutdown zone for other large whales from 1.8-m pin piles is equal to two times the modeled maximum R95 percent distance to the Level A harassment threshold for low-frequency cetaceans. 5The shutdown zones for non-large whales from monopile and 3-m pin pile installation are equal to the modeled maximum R95 percent distances to the Level A harassment threshold for harbor porpoise (the most sensitive species). The shutdown zone for non-large whales from 1.8-m pin pile installation is equal to the modeled 

maximum R95 percent distance to the Level B harassment threshold, given the Level A harassment thresholds were not exceeded for this activity (i.e., 0 m). US Wind 

requested the shutdown zone for non-large whales be identical for PSO implementation ease. 6The PAM system must be capable of detecting baleen whales at 10,000 m during pile driving. The system should also be designed to detect other marine mammals; however, it is not required these other species be detected out to 10,000 m given higher frequency calls and echolocation clicks are not typically detectable at 

large distances. 

TABLE 28—HRG SURVEY CLEARANCE AND SHUTDOWN ZONES

Marine mammal species 

Clearance 

zone 

(m2) 

Shutdown 

zone 

(m) 

North Atlantic right whale ................................................................................................................................................ 500 500 

Other ESA-listed species (i.e., fin, sei, sperm whale) ..................................................................................................... 500 100 

Other marine mammals 1 ................................................................................................................................................. 200 100 

1With the exception of seals and delphinid(s) from the genera Delphinus, Lagenorhynchus, Stenella or Tursiops, as described below. 

Soft-Start/Ramp Up 

The use of a soft-start or ramp up 

procedure is believed to provide 

additional protection to marine 

mammals by warning them or providing 

them with a chance to leave the area 

prior to the hammer or HRG equipment 

operating at full capacity. Soft-start 

typically involves initiating hammer 

operation at a reduced energy level 

(relative to full operating capacity) 

followed by a waiting period. US Wind 

would be required to utilize a soft-start 

protocol for impact pile driving of 

monopiles, 3-m pin piles, and 1.8-m pin 

piles by performing four to six strikes 

per minute at 10 to 20 percent of the 

maximum hammer energy, for a 

minimum of 20 minutes. NMFS notes 

that it is difficult to specify a reduction 

in energy for any given hammer because 

of variation across drivers and 

installation conditions. US Wind will 

reduce energy based on consideration of 

site-specific soil properties and other 

relevant operational considerations. 

HRG survey operators would be 

required to ramp-up sources when the 

acoustic sources are used unless the 

equipment operates on a binary on/off 

switch. The ramp up would involve 

starting from the smallest setting to the 

operating level over a period of 

approximately 30 minutes. 

Soft-start and ramp up would be 

required at the beginning of each day’s 

activity and at any time following a 

cessation of activity of 30 minutes or 

longer. Prior to soft-start or ramp up 

beginning, the operator must receive 

confirmation from the PSO that the 

clearance zone is clear of any marine 

mammals. 

Fishery Monitoring Surveys 

While the likelihood of US Wind’s 

fishery monitoring surveys impacting 

marine mammals is minimal, NMFS 

proposed to require US Wind to adhere 

to gear and vessel mitigation measures 

to reduce potential impacts to the extent 

practicable. In addition, all crew 

undertaking the fishery monitoring 

survey activities would be required to 

receive protected species identification 

training prior to activities occurring and 

attend the aforementioned onboarding 

training. The specific requirements that 

NMFS would set for the fishery 

monitoring surveys can be found in the 


khammond on DSKJM1Z7X2PROD with PROPOSALS2

I I 
Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 559 

regulatory text at the end of this 

proposed rulemaking. 

Based on our evaluation of the 

mitigation measures, NMFS has 

preliminarily determined that these 

proposed measures would provide the 

means of affecting the least practicable 

adverse impact on the affected species 

or stocks and their habitat, paying 

particular attention to rookeries, mating 

grounds, and areas of similar 

significance. 

Proposed Monitoring and Reporting 

In order to promulgate a rulemaking 

for an activity, section 101(a)(5)(A) of 

the MMPA states that NMFS must set 

forth requirements pertaining to the 

monitoring and reporting of such taking. 

The MMPA implementing regulations at 

50 CFR 216.104(a)(13) indicate that 

requests for authorizations must include 

the suggested means of accomplishing 

the necessary monitoring and reporting 

that will result in increased knowledge 

of the species and of the level of taking 

or impacts on populations of marine 

mammals that are expected to be 

present in the proposed action area. 

Effective reporting is critical both to 

compliance as well as ensuring that the 

most value is obtained from the required 

monitoring. 

Monitoring and reporting 

requirements prescribed by NMFS 

should contribute to improved 

understanding of one or more of the 

following: 

• Occurrence of marine mammal 

species or stocks in the area in which 

take is anticipated (e.g., presence, 

abundance, distribution, density); 

• Nature, scope, or context of likely 

marine mammal exposure to potential 

stressors/impacts (individual or 

cumulative, acute or chronic), through 

better understanding of: (1) action or 

environment (e.g., source 

characterization, propagation, ambient 

noise); (2) affected species (e.g., life 

history, dive patterns); (3) co-occurrence 

of marine mammal species with the 

action; or (4) biological or behavioral 

context of exposure (e.g., age, calving or 

feeding areas); 

• Individual marine mammal 

responses (behavioral or physiological) 

to acoustic stressors (acute, chronic, or 

cumulative), other stressors, or 

cumulative impacts from multiple 

stressors; 

• How anticipated responses to 

stressors impact either: (1) long-term 

fitness and survival of individual 

marine mammals; or (2) populations, 

species, or stocks; 

• Effects on marine mammal habitat 

(e.g., marine mammal prey species, 

acoustic habitat, or other important 

physical components of marine 

mammal habitat); and/or 

• Mitigation and monitoring 

effectiveness. 

Separately, monitoring is also 

regularly used to support mitigation 

implementation, which is referred to as 

mitigation monitoring, and monitoring 

plans typically include measures that 

both support mitigation implementation 

and increase our understanding of the 

impacts of the activity on marine 

mammals. 

During the planned activities, visual 

monitoring by NMFS-approved PSOs 

would be conducted before, during, and 

after all impact pile driving and HRG 

surveys. PAM would also be conducted 

during impact pile driving. Visual 

observations and acoustic detections 

would be used to support the activityspecific mitigation measures (e.g., 

clearance zones). To increase 

understanding of the impacts of the 

activity on marine mammals, PSOs must 

record all incidents of marine mammal 

occurrence at any distance from the 

piling locations, near the HRG acoustic 

sources. PSOs would document all 

behaviors and behavioral changes, in 

concert with distance from an acoustic 

source. The required monitoring is 

described below, beginning with PSO 

measures that are applicable to all the 

aforementioned activities, followed by 

activity-specific monitoring 

requirements. 

Protected Species Observer and PAM 

Operator Requirements 

US Wind would be required to 

employ NMFS-approved PSOs and PAM 

operators. PSOs are trained 

professionals who are tasked with visual 

monitoring for marine mammals during 

pile driving and HRG surveys. The 

primary purpose of a PSO is to carry out 

the monitoring, collect data, and, when 

appropriate, call for the implementation 

of mitigation measures. In addition to 

visual observations, NMFS would 

require US Wind to conduct PAM using 

PAM operators during impact pile 

driving and vessel transit. 

The inclusion of PAM, which would 

be conducted by NMFS-approved PAM 

operators, following a standardized 

measurement, processing methods, 

reporting metrics, and metadata 

standards for offshore wind alongside 

visual data collection is valuable to 

provide the most accurate record of 

species presence as possible, together 

with visual monitoring, and these two 

monitoring methods are well 

understood to provide best results when 

combined together (e.g., Barlow and 

Taylor, 2005; Clark et al., 2010; 

Gerrodette et al., 2011; Van Parijs et al., 

2021). Acoustic monitoring (in addition 

to visual monitoring) increases the 

likelihood of detecting marine mammals 

within the shutdown and clearance 

zones of project activities, which when 

applied in combination with required 

shutdowns helps to further reduce the 

risk of marine mammals being exposed 

to sound levels that could otherwise 

result in acoustic injury or more intense 

behavioral harassment. 

The exact configuration and number 

of PAM systems depends on the size of 

the zone(s) being monitored, the amount 

of noise expected in the area, and the 

characteristics of the signals being 

monitored. More closely spaced 

hydrophones would allow for more 

directionality, and perhaps, range to the 

vocalizing marine mammals; although, 

this approach would add additional 

costs and greater levels of complexity to 

the project. Larger baleen cetacean 

species (i.e., mysticetes), which produce 

loud and lower-frequency vocalizations, 

may be able to be heard with fewer 

hydrophones spaced at greater 

distances. However, smaller cetaceans 

(such as mid-frequency delphinids or 

odontocetes) may necessitate more 

hydrophones and to be spaced closer 

together given the shorter range of the 

shorter, mid-frequency acoustic signals 

(e.g., whistles and echolocation clicks). 

As there are no ‘‘perfect fit’’ singleoptimal-array configurations, NMFS 

will consider and approve these set-ups, 

as appropriate, on a case-by-case basis. 

Specifically, US Wind will be required 

to provide a plan that describes an 

optimal configuration for collecting the 

required marine mammal data, based on 

the real-world circumstances in the 

project area, recognizing that we will 

continue to learn more as monitoring 

results from other wind projects are 

submitted. 

NMFS does not formally administer 

any PSO or PAM operator training 

program or endorse specific providers 

but will approve PSOs and PAM 

operators that have successfully 

completed courses that meet the 

curriculum and trainer requirements 

referenced below and further specified 

in the regulatory text at the end of this 

proposed rulemaking. 

NMFS will provide PSO and PAM 

operator approvals in the context of the 

need to ensure that PSOs and PAM 

operators have the necessary training 

and/or experience to carry out their 

duties competently. In order for PSOs 

and PAM operators to be approved, 

NMFS must review and approve PSO 

and PAM operator resumes indicating 

successful completion of an acceptable 

training course. PSOs and PAM 

operators must have previous 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
560 Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 

experience observing marine mammals 

and must have the ability to work with 

all required and relevant software and 

equipment. NMFS may approve PSOs 

and PAM operators as conditional or 

unconditional. Conditional approval 

may be given to one who is trained but 

has not yet attained the requisite 

experience. Unconditional approval is 

given to one who is trained and has 

attained the necessary experience. The 

specific requirements for conditional 

and unconditional approval can be 

found in the regulatory text at the end 

of this proposed rulemaking. 

Conditionally approved PSOs and 

PAM operators would be paired with an 

unconditionally approved PSO (or PAM 

operator, as appropriate) to ensure that 

the quality of marine mammal 

observations and data recording is kept 

consistent. Additionally, activities 

requiring PSO and/or PAM operator 

monitoring must have a lead on duty. 

The visual PSO field team, in 

conjunction with the PAM team (i.e., 

marine mammal monitoring team) 

would have a lead member (designated 

as the ‘‘Lead PSO’’ or ‘‘Lead PAM 

operator’’) who would be required to 

meet the unconditional approval 

standard. 

Although PSOs and PAM operators 

must be approved by NMFS, third-party 

observer providers and/or companies 

seeking PSO and PAM operator staffing 

should expect that those having 

satisfactorily completed acceptable 

training and with the requisite 

experience (if required) will be quickly 

approved. US Wind is required to 

request PSO and PAM operator 

approvals 60 days prior to those 

personnel commencing work. An initial 

list of previously approved PSO and 

PAM operators must be submitted by 

US Wind at least 30 days prior to the 

start of the project. Should US Wind 

require additional PSOs or PAM 

operators throughout the project, US 

Wind must submit a subsequent list of 

pre-approved PSOs and PAM operators 

to NMFS at least 15 days prior to 

planned use of that PSO or PAM 

operator. A PSO may be trained and/or 

experienced as both a PSO and PAM 

operator and may perform either duty, 

pursuant to scheduling requirements 

(and vice versa). 

A minimum number of PSOs would 

be required to actively observe for the 

presence of marine mammals during 

certain project activities with more 

PSOs required as the mitigation zone 

sizes increase. A minimum number of 

PAM operators would be required to 

actively monitor for the presence of 

marine mammals during foundation 

installation. The types of equipment 

required (e.g., Big Eye binoculars on the 

pile driving vessel) are also designed to 

increase marine mammal detection 

capabilities. Specifics on these types of 

requirements can be found in the 

regulations at the end of this proposed 

rulemaking. At least three PSOs and one 

PAM operator per acoustic data stream 

(equivalent to the number of acoustic 

buoys) must be on-duty and actively 

monitoring per platform during 

foundation installation; and at least one 

PSO must be on-duty during HRG 

surveys conducted during daylight 

hours. 

In addition to monitoring duties, 

PSOs and PAM operators are 

responsible for data collection. The data 

collected by PSO and PAM operators 

and subsequent analysis provide the 

necessary information to inform an 

estimate of the amount of take that 

occurred during the project, better 

understand the impacts of the project on 

marine mammals, address the 

effectiveness of monitoring and 

mitigation measures, and to adaptively 

manage activities and mitigation in the 

future. Data reported includes 

information on marine mammal 

sightings, activity occurring at time of 

sighting, monitoring conditions, and if 

mitigative actions were taken. Specific 

data collection requirements are 

contained within the regulations at the 

end of this proposed rulemaking. 

US Wind would be required to submit 

a Pile Driving Marine Mammal 

Monitoring Plan to NMFS 180 days in 

advance of foundation installation 

activities. The Plan must include details 

regarding PSO and PAM monitoring 

protocols and equipment proposed for 

use. More specifically, the PAM portion 

of the plan must include a description 

of all proposed PAM equipment, 

address how the proposed passive 

acoustic monitoring must follow 

standardized measurement, processing 

methods, reporting metrics, and 

metadata standards for offshore wind as 

described in NOAA and BOEM 

Minimum Recommendations for Use of 

Passive Acoustic Listening Systems in 

Offshore Wind Energy Development 

Monitoring and Mitigation Programs 

(Van Parijs et al., 2021). NMFS must 

approve the plan prior to the 

commencement of foundation 

installation activities. Specific details 

on NMFS’ PSO or PAM operator 

qualifications and requirements can be 

found in Part 217—Regulations 

Governing The Taking And Importing 

Of Marine Mammals at the end of this 

proposed rulemaking. Additional 

information can be found in US Wind 

Marine Mammal Monitoring and 

Mitigation Plan (appendix B) on the 

NMFS’ website at https://

www.fisheries.noaa.gov/action/ 

incidental-take-authorization-us-windinc-construction-and-operationmaryland-offshore-wind. 

Sound Field Verification 

US Wind would be required to 

conduct SFV measurements during all 

impact pile driving activities associated 

with the installation of, at minimum, 

the first three monopile foundations. 

SFV measurements must continue until 

at least three consecutive monopiles and 

three entire jacket foundations 

demonstrate noise levels are at or below 

those modeled, assuming 10-dB of 

attenuation. Subsequent SFV 

measurements would also be required 

should larger piles be installed or if 

additional piles are driven that are 

anticipated to produce louder sound 

fields than those previously measured 

(e.g., higher hammer energy, greater 

number of strikes, etc.). The 

measurements and reporting associated 

with SFV can be found in the regulatory 

text at the end of this proposed 

rulemaking. The proposed requirements 

are extensive to ensure monitoring is 

conducted appropriately and the 

reporting frequency is such that US 

Wind would be required to make 

adjustments quickly (e.g., add 

additional sound attenuation) to ensure 

marine mammals are not experiencing 

noise levels above those considered in 

this analysis. For recommended SFV 

protocols for impact pile driving, please 

consult International Organization for 

Standardization (ISO) 18406 

Underwater acoustics—Measurement of 

radiated underwater sound from 

percussive pile driving (2017). 

Reporting 

Prior to any construction activities 

occurring, US Wind would provide a 

report to NMFS Office of Protected 

Resources that demonstrates that all US 

Wind personnel, which includes the 

vessel crews, vessel captains, PSOs, and 

PAM operators have completed all 

required trainings. 

NMFS would require standardized 

and frequent reporting from US Wind 

during the life of the regulations and 

LOA. All data collected relating to the 

Project would be recorded using 

industry-standard software (e.g., 

Mysticetus or a similar software) 

installed on field laptops and/or tablets. 

US Wind would be required to submit 

weekly, monthly, annual, and 

situational reports. The specifics of 

what we require to be reported can be 

found in the regulatory text at the end 

of this proposed rulemaking. 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 561 

Weekly Report—During foundation 

installation activities, US Wind would 

be required to compile and submit 

weekly marine mammal monitoring 

reports for foundation installation pile 

driving to NMFS Office of Protected 

Resources that document the daily start 

and stop of all pile driving activities, the 

start and stop of associated observation 

periods by PSOs, details on the 

deployment of PSOs, a record of all 

detections of marine mammals (acoustic 

and visual), any mitigation actions (or if 

mitigation actions could not be taken, 

provide reasons why), and details on the 

noise abatement system(s) (e.g., system 

type, distance deployed from the pile, 

bubble rate, etc.). Weekly reports will be 

due on Wednesday for the previous 

week (Sunday to Saturday). The weekly 

reports are also required to identify 

which turbines become operational and 

when (a map must be provided). Once 

all foundation pile installation is 

complete, weekly reports would no 

longer be required. 

Monthly Report—US Wind would be 

required to compile and submit monthly 

reports to NMFS Office of Protected 

Resources that include a summary of all 

information in the weekly reports, 

including project activities carried out 

in the previous month, vessel transits 

(number, type of vessel, and route), 

number of piles installed, all detections 

of marine mammals, and any mitigative 

actions taken. Monthly reports would be 

due on the 15th of the month for the 

previous month. The monthly report 

would also identify which turbines 

become operational and when (a map 

must be provided). Once all foundation 

pile installation is complete, monthly 

reports would no longer be required. 

Annual Reporting—US Wind would 

be required to submit an annual marine 

mammal monitoring (both PSO and 

PAM) report to NMFS Office of 

Protected Resources no later than 90 

days following the end of a given 

calendar year describing, in detail, all of 

the information required in the 

monitoring section above. A final 

annual report must be prepared and 

submitted within 30 calendar days 

following receipt of any NMFS 

comments on the draft report. 

Final 5-Year Reporting—US Wind 

would be required to submit its draft 5- 

year report(s) to NMFS Office of 

Protected Resources on all visual and 

acoustic monitoring conducted under 

the LOA within 90 calendar days of the 

completion of activities occurring under 

the LOA. A final 5-year report must be 

prepared and submitted within 60 

calendar days following receipt of any 

NMFS comments on the draft report. 

Information contained within this report 

is described at the beginning of this 

section. 

Situational Reporting—Specific 

situations encountered during the 

development of the Project would 

require immediate reporting. For 

instance, if a North Atlantic right whale 

is observed at any time by PSOs or 

project personnel, the sighting must be 

immediately (if not feasible, as soon as 

possible, and no longer than 24 hours 

after the sighting) reported to NMFS. If 

a North Atlantic right whale is 

acoustically detected at any time via a 

project-related PAM system, the 

detection must be reported as soon as 

possible and no longer than 24 hours 

after the detection to NMFS via the 24- 

hour North Atlantic right whale 

Detection Template (https://

www.fisheries.noaa.gov/resource/ 

document/passive-acoustic-reportingsystem-templates). Calling the hotline is 

not necessary when reporting PAM 

detections via the template. 

If a sighting of a stranded, entangled, 

injured, or dead marine mammal occurs, 

the sighting would be reported to NMFS 

Office of Protected Resources, the NMFS 

Greater Atlantic Stranding Coordinator 

for the New England/Mid-Atlantic area 

(866–755–6622), and the U.S. Coast 

Guard within 24 hours. If the injury or 

death was caused by a project activity, 

US Wind would be required to 

immediately cease all activities until 

NMFS Office of Protected Resources is 

able to review the circumstances of the 

incident and determine what, if any, 

additional measures are appropriate to 

ensure compliance with the terms of the 

LOA. NMFS Office of Protected 

Resources may impose additional 

measures to minimize the likelihood of 

further prohibited take and ensure 

MMPA compliance consistent with the 

adaptive management provisions 

described below and codified at 

§ 217.307. US Wind could not resume 

their activities until notified by NMFS 

Office of Protected Resources. 

In the event of a vessel strike of a 

marine mammal by any vessel 

associated with the Project, US Wind 

must immediately report the strike 

incident. If the strike occurs in the 

Greater Atlantic Region (Maine to 

Virginia), US Wind must call the NMFS 

Office of Protected Resources and 

GARFO. US Wind would be required to 

immediately cease all on-water 

activities until NMFS Office of 

Protected Resources is able to review 

the circumstances of the incident and 

determine what, if any, additional 

measures are appropriate to ensure 

compliance with the terms of the LOA. 

NMFS Office of Protected Resources 

may impose additional measures to 

minimize the likelihood of further 

prohibited take and ensure MMPA 

compliance. US Wind may, consistent 

with the adaptive management 

provisions described below and codified 

at § 217.307, not resume their activities 

until notified by NMFS. 

In the event of any lost gear associated 

with the fishery surveys, US Wind must 

report to the GARFO as soon as possible 

or within 24 hours of the documented 

time of missing or lost gear. This report 

must include information on any 

markings on the gear and any efforts 

undertaken or planned to recover the 

gear. 

The specifics of what NMFS Office of 

Protected Resources requires to be 

reported is listed at the end of this 

proposed rulemaking in the regulatory 

text. 

Sound Field Verification—US Wind 

would be required to submit interim 

SFV reports after each foundation 

installation within 48 hours. A final 

SFV report for all monopile, jacket 

foundation, and pin pile installation 

monitoring would be required within 90 

days following completion of acoustic 

monitoring. 

Adaptive Management 

The regulations governing the take of 

marine mammals incidental to US Wind 

construction activities contain an 

adaptive management component. Our 

understanding of the effects of offshore 

wind construction activities (e.g., 

acoustic stressors) on marine mammals 

continues to evolve, which makes the 

inclusion of an adaptive management 

component both valuable and necessary 

within the context of 5-year regulations. 

The monitoring and reporting 

requirements in this final rule provide 

NMFS with information that helps us to 

better understand the impacts of the 

project’s activities on marine mammals 

and informs our consideration of 

whether any changes to mitigation and 

monitoring are appropriate. The use of 

adaptive management allows NMFS to 

consider new information and modify 

mitigation, monitoring, or reporting 

requirements, as appropriate, with input 

from US Wind regarding practicability, 

if such modifications will have a 

reasonable likelihood of more 

effectively accomplishing the goal of the 

measures. 

The following are some of the 

possible sources of new information to 

be considered through the adaptive 

management process: (1) results from 

monitoring reports, including the 

weekly, monthly, situational, and 

annual reports required; (2) results from 

marine mammal and sound research; 

and (3) any information which reveals 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
562 Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 

that marine mammals may have been 

taken in a manner, extent, or number 

not authorized by these regulations or 

subsequent LOA. During the course of 

the rule, US Wind (and other LOA 

Holders conducting offshore wind 

development activities) are required to 

participate in one or more adaptive 

management meetings convened by 

NMFS and/or BOEM, in which the 

above information will be summarized 

and discussed in the context of potential 

changes to the mitigation or monitoring 

measures. 

Negligible Impact Analysis and 

Determination 

NMFS has defined negligible impact 

as an impact resulting from the 

specified activity that cannot be 

reasonably expected to, and is not 

reasonably likely to, adversely affect the 

species or stock through effects on 

annual rates of recruitment or survival 

(50 CFR 216.103). A negligible impact 

finding is based on the lack of likely 

adverse effects on annual rates of 

recruitment or survival (i.e., populationlevel effects). An estimate of the number 

of takes alone is not enough information 

on which to base an impact 

determination. In addition to 

considering estimates of the number of 

marine mammals that might be ‘‘taken’’ 

by mortality, serious injury, Level A 

harassment and Level B harassment, we 

consider other factors, such as the likely 

nature of any behavioral responses (e.g., 

intensity, duration), the context of any 

such responses (e.g., critical 

reproductive time or location, 

migration), as well as effects on habitat, 

and the likely effectiveness of 

mitigation. We also assess the number, 

intensity, and context of estimated takes 

by evaluating this information relative 

to population status. Consistent with the 

1989 preamble for NMFS’ implementing 

regulations (54 FR 40338, September 29, 

1989), the impacts from other past and 

ongoing anthropogenic activities are 

incorporated into this analysis via their 

impacts on the environmental baseline 

(e.g., as reflected in the regulatory status 

of the species, population size and 

growth rate where known, ongoing 

sources of human-caused mortality, or 

ambient noise levels). 

In the Estimated Take section, we 

estimated the maximum number of 

takes by Level A harassment and Level 

B harassment that could occur from US 

Wind’s specified activities based on the 

methods described. The impact that any 

given take would have is dependent on 

many case-specific factors that need to 

be considered in the negligible impact 

analysis (e.g., the context of behavioral 

exposures such as duration or intensity 

of a disturbance, the health of impacted 

animals, the status of a species that 

incurs fitness-level impacts to 

individuals, etc.). In this proposed rule, 

we evaluate the likely impacts of the 

enumerated harassment takes that are 

proposed to be authorized in the context 

of the specific circumstances 

surrounding these predicted takes. We 

also collectively evaluate this 

information, as well as other more taxaspecific information and mitigation 

measure effectiveness, in group-specific 

discussions that support our negligible 

impact conclusions for each stock. As 

described above, no serious injury or 

mortality is expected or proposed to be 

authorized for any species or stock. 

The Description of the Specified 

Activities section describes US Wind 

specified activities proposed for the 

project that may result in take of marine 

mammals and an estimated schedule for 

conducting those activities. US Wind 

has provided a realistic construction 

schedule although we recognize 

schedules may shift for a variety of 

reasons (e.g., weather or supply delays). 

However, the total amount of take 

would not exceed the 3-year totals and 

maximum annual total in any given year 

indicated in tables 24 and 25, 

respectively. 

We base our analysis and preliminary 

negligible impact determination on the 

maximum number of takes that could 

occur and are proposed to be authorized 

annually and across the effective period 

of these regulations, and extensive 

qualitative consideration of other 

contextual factors that influence the 

degree of impact of the takes on the 

affected individuals and the number 

and context of the individuals affected. 

As stated before, the number of takes, 

both maximum annual and 5-year total, 

alone are only a part of the analysis. 

To avoid repetition, we provide some 

general analysis in this Negligible 

Impact Analysis and Determination 

section that applies to all the species 

listed in table 6 given that some of the 

anticipated effects of US Wind’s 

construction activities on marine 

mammals are expected to be relatively 

similar in nature. Then, we subdivide 

into more detailed discussions for 

mysticetes, odontocetes, and pinnipeds 

which have broad life history traits that 

support an overarching discussion of 

some factors considered within the 

analysis for those groups (e.g., habitatuse patterns, high-level differences in 

feeding strategies). 

Last, we provide a negligible impact 

determination for each species or stock, 

providing species or stock-specific 

information or analysis, where 

appropriate, for example, for North 

Atlantic right whales given the 

population status. Organizing our 

analysis by grouping species or stocks 

that share common traits or that would 

respond similarly to effects of US 

Wind’s activities, and then providing 

species- or stock-specific information 

allows us to avoid duplication while 

ensuring that we have analyzed the 

effects of the specified activities on each 

affected species or stock. It is important 

to note that in the group or species 

sections, we base our negligible impact 

analysis on the maximum annual take 

that is predicted under the 5-year rule; 

however, the majority of the impacts are 

associated with WTG, Met tower, and 

OSS foundation installation, which are 

schedule to occur within the first 1 to 

3 years (2025 through 2027) (tables 23, 

24, and 25). 

As described previously, no serious 

injury or mortality is anticipated or 

proposed to be authorized in this rule. 

Any Level A harassment proposed to be 

authorized would be in the form of 

auditory injury (i.e., PTS) and not nonauditory injury (e.g., lung injury or 

gastrointestinal injury from 

detonations). The amount of harassment 

US Wind has requested, and NMFS 

proposes to authorize, is based on 

exposure models that consider the 

outputs of acoustic source and 

propagation models and other data such 

as frequency of occurrence or group 

sizes. Several conservative parameters 

and assumptions are ingrained into 

these models, modeling the impact 

installation of all piles at a maximum 

hammer energy and application of the 

May sound speed profile to all months 

within a given season. The exposure 

model results do not reflect any 

mitigation measures (other than 10-dB 

sound attenuation) or avoidance 

response. The amount of take requested 

and proposed to be authorized also 

reflects careful consideration of other 

data (e.g., group size data) and, for Level 

A harassment potential of some large 

whales, the consideration of mitigation 

measures. For all species, the amount of 

take proposed to be authorized 

represents the maximum amount of 

Level A harassment and Level B 

harassment that could occur. 

Behavioral Disturbance 

In general, NMFS anticipates that 

impacts on an individual that has been 

harassed are likely to be more intense 

when exposed to higher received levels 

and for a longer duration (though this is 

in no way a strictly linear relationship 

for behavioral effects across species, 

individuals, or circumstances) and less 

severe impacts result when exposed to 

lower received levels and for a brief 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 563 

duration. However, there is also growing 

evidence of the importance of 

contextual factors such as distance from 

a source in predicting marine mammal 

behavioral response to sound—i.e., 

sounds of a similar level emanating 

from a more distant source have been 

shown to be less likely to evoke a 

response of equal magnitude (DeRuiter 

and Doukara, 2012; Falcone et al., 

2017). As described in the Potential 

Effects of Specified Activities on Marine 

Mammals and their Habitat section, the 

intensity and duration of any impact 

resulting from exposure to US Wind’s 

activities is dependent upon a number 

of contextual factors including, but not 

limited to, sound source frequencies, 

whether the sound source is moving 

towards the animal, hearing ranges of 

marine mammals, behavioral state at 

time of exposure, status of individual 

exposed (e.g., reproductive status, age 

class, health) and an individual’s 

experience with similar sound sources. 

Southall et al. (2021), Ellison et al. 

(2012) and Moore and Barlow (2013), 

among others, emphasize the 

importance of context (e.g., behavioral 

state of the animals, distance from the 

sound source) in evaluating behavioral 

responses of marine mammals to 

acoustic sources. Harassment of marine 

mammals may result in behavioral 

modifications (e.g., avoidance, 

temporary cessation of foraging or 

communicating, changes in respiration 

or group dynamics, masking) or may 

result in auditory impacts such as 

hearing loss. In addition, some of the 

lower-level physiological stress 

responses (e.g., change in respiration, 

change in heart rate) discussed 

previously would likely co-occur with 

the behavioral modifications, although 

these physiological responses are more 

difficult to detect, and fewer data exist 

relating these responses to specific 

received levels of sound. Take by Level 

B harassment, then, may have a stressrelated physiological component as 

well; however, we would not expect US 

Wind’s activities to produce conditions 

of long-term and continuous exposure to 

noise leading to long-term physiological 

stress responses in marine mammals 

that could affect reproduction or 

survival. 

In the range of behavioral effects that 

might be expected to be part of a 

response that qualifies as an instance of 

Level B harassment by behavioral 

disturbance (which by nature of the way 

it is modeled/counted, occurs within 1 

day), the less severe end might include 

exposure to comparatively lower levels 

of a sound, at a greater distance from the 

animal, for a few or several minutes. A 

less severe exposure of this nature could 

result in a behavioral response such as 

avoiding an area that an animal would 

otherwise have chosen to move through 

or feed in for some amount of time or 

breaking off one or a few feeding bouts. 

More severe effects could occur if an 

animal gets close enough to the source 

to receive a comparatively higher level, 

is exposed continuously to one source 

for a longer time or is exposed 

intermittently to different sources 

throughout a day. Such effects might 

result in an animal having a more severe 

flight response and leaving a larger area 

for a day or more or potentially losing 

feeding opportunities for a day. 

However, such severe behavioral effects 

are expected to occur infrequently. 

Many species perform vital functions, 

such as feeding, resting, traveling, and 

socializing on a diel cycle (24-hour 

cycle). Behavioral reactions to noise 

exposure, when taking place in a 

biologically important context, such as 

disruption of critical life functions, 

displacement, or avoidance of important 

habitat, are more likely to be significant 

if they last more than 1 day or recur on 

subsequent days (Southall et al., 2007) 

due to diel and lunar patterns in diving 

and foraging behaviors observed in 

many cetaceans (Baird et al., 2008; 

Barlow et al., 2020; Henderson et al., 

2016; Schorr et al., 2014). It is important 

to note the water depth in the Project 

Area is shallow (ranging up to 10–45 m 

in the ECRs, and 13 to 41.5 m in the 

Lease Area) and deep diving species, 

such as sperm whales, are not expected 

to be engaging in deep foraging dives 

when exposed to noise above NMFS 

harassment thresholds during the 

specified activities. Therefore, we do 

not anticipate impacts to deep foraging 

behavior to be impacted by the specified 

activities. 

It is also important to identify that the 

estimated number of takes does not 

necessarily equate to the number of 

individual animals US Wind expects to 

harass (which is lower), but rather to the 

instances of take (i.e., exposures above 

the Level B harassment thresholds) that 

may occur. These instances may 

represent either seconds to minutes for 

HRG surveys, or, in some cases, longer 

durations of exposure within a day (e.g., 

pile driving). Some individuals of a 

species may experience recurring 

instances of take over multiple days 

throughout the year while some 

members of a species or stock may 

experience one exposure as they move 

through an area, which means that the 

number of individuals taken is smaller 

than the total estimated takes. In short, 

for species that are more likely to be 

migrating through the area and/or for 

which only a comparatively smaller 

number of takes are predicted (e.g., 

some of the mysticetes), it is more likely 

that each take represents a different 

individual whereas for non-migrating 

species with larger amounts of predicted 

take, we expect that the total anticipated 

takes represent exposures of a smaller 

number of individuals of which some 

would be taken across multiple days. 

For US Wind, impact pile driving of 

foundation piles is most likely to result 

in a higher magnitude and severity of 

behavioral disturbance than HRG 

surveys. Impact pile driving has higher 

source levels and longer durations (on 

an annual basis) than HRG surveys. 

HRG survey equipment also produces 

much higher frequencies than pile 

driving, resulting in minimal sound 

propagation. While impact pile driving 

for foundation installation is anticipated 

to be most impactful for these reasons, 

impacts are minimized through 

implementation of mitigation measures, 

including use of a sound attenuation 

system, soft-starts, the implementation 

of clearance zones that would facilitate 

a delay to pile driving commencement, 

and implementation of shutdown zones. 

All these measures are designed to 

avoid or minimize harassment. For 

example, given sufficient notice through 

the use of soft-start, marine mammals 

are expected to move away from a 

sound source that is disturbing prior to 

becoming exposed to very loud noise 

levels. The requirement to couple visual 

monitoring and PAM before and during 

all foundation installation will increase 

the overall capability to detect marine 

mammals compared to one method 

alone. 

Occasional, milder behavioral 

reactions are unlikely to cause long-term 

consequences for individual animals or 

populations, and even if some smaller 

subset of the takes is in the form of a 

longer (several hours or a day) and more 

severe response, if they are not expected 

to be repeated over numerous or 

sequential days, impacts to individual 

fitness are not anticipated. Also, the 

effect of disturbance is strongly 

influenced by whether it overlaps with 

biologically important habitats when 

individuals are present—avoiding 

biologically important habitats will 

provide opportunities to compensate for 

reduced or lost foraging (Keen et al., 

2021). Nearly all studies and experts 

agree that infrequent exposures of a 

single day or less are unlikely to impact 

an individual’s overall energy budget 

(Farmer et al., 2018; Harris et al., 2017; 

King et al., 2015; National Academy of 

Science, 2017; New et al., 2014; 

Southall et al., 2007; Villegas-Amtmann 

et al., 2015). 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
564 Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 

Temporary Threshold Shift (TTS) 

TTS is one form of Level B 

harassment that marine mammals may 

incur through exposure to US Wind’s 

activities and, as described earlier, the 

proposed takes by Level B harassment 

may represent takes in the form of 

behavioral disturbance, TTS, or both. As 

discussed in the Potential Effects of 

Specified Activities on Marine 

Mammals and their Habitat section, in 

general, TTS can last from a few 

minutes to days, be of varying degree, 

and occur across different frequency 

bandwidths, all of which determine the 

severity of the impacts on the affected 

individual, which can range from minor 

to more severe. Impact pile driving is a 

broadband noise sources but generates 

sounds in the lower frequency ranges 

(with most of the energy below 1–2 kHz, 

but with a small amount energy ranging 

up to 20 kHz); therefore, in general and 

all else being equal, we would 

anticipate the potential for TTS is 

higher in low-frequency cetaceans (i.e., 

mysticetes) than other marine mammal 

hearing groups and would be more 

likely to occur in frequency bands in 

which they communicate. However, we 

would not expect the TTS to span the 

entire communication or hearing range 

of any species given that the frequencies 

produced by these activities do not span 

entire hearing ranges for any particular 

species. Additionally, though the 

frequency range of TTS that marine 

mammals might sustain would overlap 

with some of the frequency ranges of 

their vocalizations, the frequency range 

of TTS from US Wind’s pile driving 

activities would not typically span the 

entire frequency range of one 

vocalization type, much less span all 

types of vocalizations or other critical 

auditory cues for any given species. In 

addition, the proposed mitigation 

measures further reduce the potential 

for TTS in mysticetes. 

Generally, both the degree of TTS and 

the duration of TTS would be greater if 

the marine mammal is exposed to a 

higher level of energy (which would 

occur when the peak dB level is higher 

or the duration is longer). The threshold 

for the onset of TTS was discussed 

previously (refer back to Estimated 

Take). However, source level alone is 

not a predictor of TTS. An animal 

would have to approach closer to the 

source or remain in the vicinity of the 

sound source appreciably longer to 

increase the received SEL, which would 

be difficult considering the proposed 

mitigation and the nominal speed of the 

receiving animal relative to the 

stationary sources such as impact pile 

driving. The recovery time of TTS is 

also of importance when considering 

the potential impacts from TTS. In TTS 

laboratory studies (as discussed in 

Potential Effects of Specified Activities 

on Marine Mammals and Their Habitat), 

some using exposures of almost an hour 

in duration or up to 217 SEL, almost all 

individuals recovered within 1 day (or 

less, often in minutes) and we note that 

while the pile driving activities last for 

hours a day, it is unlikely that most 

marine mammals would stay in the 

close vicinity of the source long enough 

to incur more severe TTS. Overall, given 

the small number of instances that any 

individual might incur TTS, the low 

degree of TTS and the short, anticipated 

duration, and the unlikely scenario that 

any TTS overlapped the entirety of a 

critical hearing range, it is unlikely that 

TTS (of the nature expected to result 

from the project’s activities) would 

result in behavioral changes or other 

impacts that would impact any 

individual’s (of any hearing sensitivity) 

reproduction or survival. 

Permanent Threshold Shift (PTS) 

NMFS proposes to authorize a very 

small amount of take by PTS to some 

marine mammal individuals. The 

numbers of proposed annual takes by 

Level A harassment are relatively low 

for all marine mammal stocks and 

species (table 23). The only activities 

incidental to which we anticipate PTS 

may occur is from exposure to impact 

pile driving, which produces sounds 

that are both impulsive and primarily 

concentrated in the lower frequency 

ranges (below 1 kHz) (David, 2006; 

Krumpel et al., 2021). 

There are no PTS data on cetaceans 

and only one instance of PTS being 

induced in older harbor seals 

(Reichmuth et al., 2019). However, 

available TTS data (of mid-frequency 

hearing specialists exposed to mid- or 

high-frequency sounds (Southall et al., 

2007; NMFS, 2018; Southall et al., 

2019)) suggest that most threshold shifts 

occur in the frequency range of the 

source up to one octave higher than the 

source. We would anticipate a similar 

result for PTS. Further, no more than a 

small degree of PTS is expected to be 

associated with any of the incurred 

Level A harassment, given it is unlikely 

that animals would stay in the close 

vicinity of a source for a duration long 

enough to produce more than a small 

degree of PTS. 

PTS would consist of minor 

degradation of hearing capabilities 

occurring predominantly at frequencies 

one-half to one octave above the 

frequency of the energy produced by 

pile driving (i.e., the low-frequency 

region below 2 kHz) (Cody and 

Johnstone, 1981; McFadden, 1986; 

Finneran, 2015), not severe hearing 

impairment. If hearing impairment 

occurs from impact pile driving, it is 

most likely that the affected animal 

would lose a few decibels in its hearing 

sensitivity, which in most cases is not 

likely to meaningfully affect its ability 

to forage and communicate with 

conspecifics. In addition, during impact 

pile driving, given sufficient notice 

through use of soft-start prior to 

implementation of full hammer energy 

during impact pile driving, marine 

mammals are expected to move away 

from a sound source that is disturbing 

prior to it resulting in severe PTS. 

Auditory Masking or Communication 

Impairment 

The ultimate potential impacts of 

masking on an individual are similar to 

those discussed for TTS (e.g., decreased 

ability to communicate, forage 

effectively, or detect predators), but an 

important difference is that masking 

only occurs during the time of the 

signal, versus TTS, which continues 

beyond the duration of the signal. Also, 

though masking can result from the sum 

of exposure to multiple signals, none of 

which might individually cause TTS. 

Fundamentally, masking is referred to 

as a chronic effect because one of the 

key potential harmful components of 

masking is its duration—the fact that an 

animal would have reduced ability to 

hear or interpret critical cues becomes 

much more likely to cause a problem 

the longer it is occurring. Inherent in the 

concept of masking is the fact that the 

potential for the effect is only present 

during the times that the animal and the 

source are in close enough proximity for 

the effect to occur (and further, this time 

period would need to coincide with a 

time that the animal was utilizing 

sounds at the masked frequency). 

As our analysis has indicated, for this 

project we expect that impact pile 

driving foundations have the greatest 

potential to mask marine mammal 

signals, and this pile driving may occur 

for several, albeit intermittent, hours per 

day, for multiple days per year. Masking 

is fundamentally more of a concern at 

lower frequencies (which are pile 

driving dominant frequencies), because 

low-frequency signals propagate 

significantly further than higher 

frequencies and because they are more 

likely to overlap both the narrower lowfrequency calls of mysticetes, as well as 

many non-communication cues related 

to fish and invertebrate prey, and 

geologic sounds that inform navigation. 

However, the area in which masking 

would occur for all marine mammal 

species and stocks (e.g., predominantly 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 565 

in the vicinity of the foundation pile 

being driven) is small relative to the 

extent of habitat used by each species 

and stock. As mentioned above, the 

Project Area does not overlap critical 

habitat for any species, and temporary 

avoidance of the pile driving area by 

marine mammals would likely displace 

animals to areas of sufficient habitat. In 

summary, the nature of US Wind’s 

activities, paired with habitat use 

patterns by marine mammals, does not 

support the likelihood that the level of 

masking that could occur would have 

the potential to affect reproductive 

success or survival. Therefore, we are 

not predicting take due to masking 

effects, and are not proposing to 

authorize such take. 

Impacts on Habitat and Prey 

Construction activities may result in 

fish and invertebrate mortality or injury 

very close to the source, and all of US 

Wind’s activities may cause some fish to 

leave the area of disturbance. It is 

anticipated that any mortality or injury 

would be limited to a very small subset 

of available prey and the 

implementation of mitigation measures 

such as the use of a noise attenuation 

system during impact pile driving 

would further limit the degree of 

impact. Behavioral changes in prey in 

response to construction activities could 

temporarily impact marine mammals’ 

foraging opportunities in a limited 

portion of the foraging range but, 

because of the relatively small area of 

the habitat that may be affected at any 

given time (e.g., around a pile being 

driven) and the temporary nature of the 

disturbance on prey species, the impacts 

to marine mammal habitat are not 

expected to cause significant or longterm negative consequences. 

Cable presence is not anticipated to 

impact marine mammal habitat as these 

would be buried, and any 

electromagnetic fields emanating from 

the cables are not anticipated to result 

in consequences that would impact 

marine mammals’ prey to the extent 

they would be unavailable for 

consumption. Although many species of 

marine mammal prey can detect 

electromagnetic fields, previous studies 

have shown little impacts on habitat use 

(Hutchinson et al., 2018). Burying the 

cables and the inclusion of protective 

shielding on cables will also minimize 

any impacts of electromagnetic fields on 

marine mammal prey. 

The presence of wind turbines within 

the Lease Area could have longer-term 

impacts on marine mammal habitat, as 

the project would result in the 

persistence of the structures within 

marine mammal habitat for more than 

30 years. The presence of structures 

such as wind turbines is, in general, 

likely to result in certain oceanographic 

effects in the marine environment, and 

may alter aggregations and distribution 

of marine mammal zooplankton prey 

through changing the strength of tidal 

currents and associated fronts, changes 

in stratification, primary production, the 

degree of mixing, and stratification in 

the water column (Schultze et al., 2020; 

Chen et al., 2021; Johnson et al., 2021; 

Christiansen et al., 2022; Dorrell et al., 

2022). 

As discussed in the Potential Effects 

of Specified Activities on Marine 

Mammals and their Habitat section, the 

project would consist of no more than 

119 foundations (114 WTGs, 4 OSSs, 1 

Met tower) in the Lease Area, which 

will gradually become operational 

following construction completion. 

While there are likely to be 

oceanographic impacts from the 

presence of operating turbines, 

meaningful oceanographic impacts 

relative to stratification and mixing that 

would significantly affect marine 

mammal foraging and prey over large 

areas in key foraging habitats are not 

anticipated from the US Wind activities 

covered under these proposed 

regulations, nor is the Project area 

located in the vicinity of any key marine 

mammal foraging areas. For these 

reasons, if oceanographic features are 

affected by the project during the 

effective period of the proposed 

regulations, the impact on marine 

mammal habitat and their prey is likely 

to be comparatively minor. 

Mitigation To Reduce Impacts on All 

Species 

This proposed rulemaking includes a 

variety of mitigation measures designed 

to minimize impacts on all marine 

mammals, with a focus on North 

Atlantic right whales (the latter is 

described in more detail below). For 

impact pile driving of foundation piles, 

nine overarching mitigation measures 

are proposed, which are intended to 

reduce both the number and intensity of 

marine mammal takes: (1) seasonal/time 

of day work restrictions; (2) use of 

multiple PSOs to visually observe for 

marine mammals (with any detection 

within specifically designated zones 

triggering a delay or shutdown); (3) use 

of PAM to acoustically detect marine 

mammals, with a focus on detecting 

baleen whales (with any detection 

within designated zones triggering delay 

or shutdown); (4) implementation of 

clearance zones; (5) implementation of 

shutdown zones; (6) use of soft-start; (7) 

use of noise attenuation technology; (8) 

maintaining situational awareness of 

marine mammal presence through the 

requirement that any marine mammal 

sighting(s) by US Wind’s personnel 

must be reported to PSOs; (9) sound 

field verification monitoring; and (10) 

Vessel Strike Avoidance measures to 

reduce the risk of a collision with a 

marine mammal and vessel. For HRG 

surveys, we are requiring six measures: 

(1) measures specifically for Vessel 

Strike Avoidance; (2) specific 

requirements during daytime HRG 

surveys; (3) implementation of clearance 

zones; (4) implementation of shutdown 

zones; (5) use of ramp-up of acoustic 

sources; and (6) maintaining situational 

awareness of marine mammal presence 

through the requirement that any 

marine mammal sighting(s) by US 

Wind’s personnel must be reported to 

PSOs. 

NMFS prescribes mitigation measures 

based on the following rationale. For 

activities with large harassment 

isopleths, US Wind would be required 

to reduce the noise levels generated to 

the lowest levels practicable and would 

be required to ensure that they do not 

exceed a noise footprint above that 

which was modeled, assuming a 10-dB 

attenuation. Use of a soft-start during 

impact pile driving will allow animals 

to move away from (i.e., avoid) the 

sound source prior to applying higher 

hammer energy levels needed to install 

the pile (US Wind would not use a 

hammer energy greater than necessary 

to install piles). Similarly, ramp-up 

during HRG surveys would allow 

animals to move away and avoid the 

acoustic sources before they reach their 

maximum energy level. For all 

activities, clearance zone and shutdown 

zone implementation, which are 

required when marine mammals are 

within given distances associated with 

certain impact thresholds for all 

activities, would reduce the magnitude 

and severity of marine mammal take. 

Additionally, the use of multiple PSOs 

(WTG, OSS, and Met tower foundation 

installation; HRG surveys), PAM (for 

impact foundation installation), and 

maintaining awareness of marine 

mammal sightings reported in the region 

(WTG, OSS, and Met tower foundation 

installation; HRG surveys) would aid in 

detecting marine mammals that would 

trigger the implementation of the 

mitigation measures. The reporting 

requirements, including SFV reporting 

(for foundation installation and 

foundation operation), will assist NMFS 

in identifying if impacts beyond those 

analyzed in this proposed rule are 

occurring, potentially leading to the 

need to enact adaptive management 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
566 Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 

measures in addition to or in the place 

of the proposed mitigation measures. 

Mysticetes 

Five mysticete species (comprising 

five stocks) of cetaceans (North Atlantic 

right whale, humpback whale, fin 

whale, sei whale, and minke whale) 

may be taken by harassment. These 

species, to varying extents, utilize the 

specified geographic region, including 

the Project Area, for the purposes of 

migration, foraging, and socializing. 

Mysticetes are in the low-frequency 

hearing group. 

Behavioral data on mysticete 

reactions to pile driving noise are scant. 

Kraus et al. (2019) predicted that the 

three main impacts of offshore wind 

farms on marine mammals would 

consist of displacement, behavioral 

disruptions, and stress. Broadly, we can 

look to studies that have focused on 

other noise sources such as seismic 

surveys and military training exercises, 

which suggest that exposure to loud 

signals can result in avoidance of the 

sound source (or displacement if the 

activity continues for a longer duration 

in a place where individuals would 

otherwise have been staying, which is 

less likely for mysticetes in this area), 

disruption of foraging activities (if they 

are occurring in the area), local masking 

around the source, associated stress 

responses, and impacts to prey, as well 

as TTS or PTS in some cases. 

Mysticetes encountered in the Project 

Area are expected to primarily be 

migrating and, to a lesser degree, may be 

engaged in foraging behavior. The extent 

to which an animal engages in these 

behaviors in the area is species-specific 

and varies seasonally. Many mysticetes 

are expected to predominantly be 

migrating through the Project Area 

towards or from feeding grounds located 

further north (e.g., southern New 

England region, Gulf of Maine, Canada). 

While we acknowledged above that 

mortality, hearing impairment, or 

displacement of mysticete prey species 

may result locally from impact pile 

driving, given the very short duration of 

and broad availability of prey species in 

the area and the availability of 

alternative suitable foraging habitat for 

the mysticete species most likely to be 

affected, any impacts on mysticete 

foraging is expected to be minor. Whales 

temporarily displaced from the Project 

Area are expected to have sufficient 

remaining feeding habitat available to 

them and would not be prevented from 

feeding in other areas within the 

biologically important feeding habitats 

found further north. In addition, any 

displacement of whales or interruption 

of foraging bouts would be expected to 

be relatively temporary in nature. 

The potential for repeated exposures 

is dependent upon the residency time of 

whales, with migratory animals unlikely 

to be exposed on repeated occasions and 

animals remaining in the area to be 

more likely exposed repeatedly. For 

mysticetes, where relatively low 

amounts of species-specific take by 

Level B harassment are predicted 

(compared to the abundance of each 

mysticete species or stock, such as is 

indicated in table 25) and movement 

patterns suggest that individuals would 

not necessarily linger in a particular 

area for multiple days, each predicted 

take likely represents an exposure of a 

different individual; the behavioral 

impacts would, therefore, be expected to 

occur within a single day within a 

year—an amount that NMFS would not 

expect to impact reproduction or 

survival. Species with longer residence 

time in the Project Area may be subject 

to repeated exposures across multiple 

days. 

In general, for this project, the 

duration of exposures would not be 

continuous throughout any given day, 

and pile driving would not occur on all 

consecutive days within a given year 

due to weather delays or any number of 

logistical constraints US Wind has 

identified. Species-specific analysis 

regarding potential for repeated 

exposures and impacts is provided 

below. 

Fin, humpback, minke, and sei 

whales are the only mysticete species 

for which PTS is anticipated and 

proposed to be authorized. As described 

previously, PTS for mysticetes from 

some project activities may overlap 

frequencies used for communication, 

navigation, or detecting prey. However, 

given the nature and duration of the 

activity, the mitigation measures, and 

likely avoidance behavior, any PTS is 

expected to be of a small degree, would 

be limited to frequencies where pile 

driving noise is concentrated (i.e., only 

a small subset of their expected hearing 

range) and would not be expected to 

impact reproductive success or survival. 

North Atlantic Right Whale 

North Atlantic right whales are listed 

as endangered under the ESA and as 

both depleted and strategic stocks under 

the MMPA. As described in the 

Potential Effects of the Specified 

Activities on Marine Mammals and 

Their Habitat section, North Atlantic 

right whales are threatened by a low 

population abundance, higher than 

average mortality rates, and lower than 

average reproductive rates. Recent 

studies have reported individuals 

showing high stress levels (e.g., 

Corkeron et al., 2017) and poor health, 

which has further implications on 

reproductive success and calf survival 

(Christiansen et al., 2020; Stewart et al., 

2021; Stewart et al., 2022). As described 

below, a UME has been designated for 

North Atlantic right whales. Given this, 

the status of the North Atlantic right 

whale population is of heightened 

concern and, therefore, merits 

additional analysis and consideration. 

No injury or mortality is anticipated or 

proposed for authorization for this 

species. 

For North Atlantic right whales, this 

proposed rule would allow for the 

authorization of up to ten takes, by 

Level B harassment only, over the 5-year 

period, with a maximum annual 

allowable take by Level B harassment of 

four (equating to approximately 1.18 

percent of the stock abundance, if each 

take were considered to be of a different 

individual). The Project Area is known 

as a migratory corridor for North 

Atlantic right whales and given the 

nature of migratory behavior (e.g., 

continuous path), as well as the low 

number of total takes, we anticipate that 

few, if any, of the instances of take 

would represent repeat takes of any 

individual, though it could occur if 

whales are engaged in opportunistic 

foraging behavior. Barco et al. (2015) 

observed North Atlantic right whales 

engaging in open mouth behavior, 

which is suggestive, though not 

necessarily indicative, of feeding. While 

opportunistic foraging may occur in the 

Project area, the area does not support 

prime foraging habitat. 

The highest density of North Atlantic 

right whales in the Project Area occurs 

in the winter (table 12). The MidAtlantic, including the Project Area, 

may be a stopover site for migrating 

North Atlantic right whales moving to 

or from southeastern calving grounds. 

North Atlantic right whales have been 

acoustically detected in the vicinity of 

the Project Area year-round (Bailey et 

al., 2018) with the highest occurrences 

documented during late winter/early 

spring. Similarly, the waters off the 

coast of Maryland, including those 

surrounding the Project Area in the 

Maryland Wind Energy Area (MD 

WEA), have documented North Atlantic 

right whale presence as the area is an 

important migratory route for the 

species to the northern feeding areas 

near the Gulf of Maine and Georges 

Banks and to their southern breeding 

and calving grounds off the southeastern 

U.S. (CETAP, 1982; LaBrecque et al., 

2015; Salisbury et al., 2016; Davis et al., 

2017). However, comparatively, the 

Project Area is not known as an 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 567 

important area for feeding, breeding, or 

calving. 

North Atlantic right whales range 

outside the Project Area for their main 

feeding, breeding, and calving activities 

(Hayes et al., 2023). Additional 

qualitative observations include animals 

feeding and socializing in New England 

waters, north of the MD WEA 

(Quintana-Rizzo et al., 2021). The North 

Atlantic right whales observed north of 

the MD WEA were primarily 

concentrated in the northeastern and 

southeastern sections of the 

Massachusetts WEA (MA WEA) during 

the summer (June–August) and winter 

(December–February). North Atlantic 

right whale distribution did shift to the 

west into the Rhode Island/ 

Massachusetts (RI/MA WEA) in the 

spring (March–May). Quintana-Rizzo et 

al. (2021) found that approximately 23 

percent of the right whale population is 

present from December through May, 

and the mean residence time has tripled 

to an average of 13 days during these 

months. The MD WEA is not in or near 

these areas important to feeding, 

breeding, and calving activities. 

In general, North Atlantic right 

whales in the Project Area are expected 

to be engaging in migratory behavior. 

Given the species’ migratory behavior in 

the Project Area, we anticipate 

individual whales would be typically 

migrating through the area during most 

months when foundation installation 

would occur (given the seasonal 

restrictions on foundation installation, 

rather than lingering for extended 

periods of time). Other work that 

involves much smaller harassment 

zones (e.g., HRG surveys) may also 

occur during periods when North 

Atlantic right whales are using the 

habitat for migration. It is important to 

note the activities occurring from 

December through May that may impact 

North Atlantic right whale would be 

HRG surveys which are planned to take 

place during years 2 and 3 for only 14 

days each year from April through June 

and would not result in very high 

received levels. Across all years, if an 

individual were to be exposed during a 

subsequent year, the impact of that 

exposure is likely independent of the 

previous exposure given the duration 

between exposures. 

As described in the Description of 

Marine Mammals in the Geographic 

Area of Specified Activities, North 

Atlantic right whales are presently 

experiencing an ongoing UME 

(beginning in June 2017). Preliminary 

findings support human interactions, 

specifically vessel strikes and 

entanglements, as the cause of death for 

the majority of North Atlantic right 

whales. Given the current status of the 

North Atlantic right whale, the loss of 

even one individual could significantly 

impact the population. No mortality, 

serious injury, or injury of North 

Atlantic right whales as a result of the 

project is expected or proposed to be 

authorized. Any disturbance to North 

Atlantic right whales due to US Wind’s 

activities is expected to result in 

temporary avoidance of the immediate 

area of construction. As no injury, 

serious injury, or mortality is expected 

or proposed to be authorized, and Level 

B harassment of North Atlantic right 

whales will be reduced to the level of 

least practicable adverse impact through 

use of mitigation measures, the 

proposed number of takes of North 

Atlantic right whales would not 

exacerbate or compound the effects of 

the ongoing UME. 

As described in the general Mysticetes 

section above, foundation installation is 

likely to result in the highest amount of 

annual take and is of greatest concern 

given loud source levels. This activity 

would likely be limited to up to 119 

days (114 for WTG monopile 

foundations, 4 days for OSS jacket 

foundations, and 1 day for Met tower 

pin pile foundations) over a maximum 

of 3 years, during times when, based on 

the best available scientific data, North 

Atlantic right whales are less frequently 

encountered due to their migratory 

behavior. The potential types, severity, 

and magnitude of impacts are also 

anticipated to mirror that described in 

the general Mysticetes section above, 

including avoidance (the most likely 

outcome), changes in foraging or 

vocalization behavior, masking, a small 

amount of TTS, and temporary 

physiological impacts (e.g., change in 

respiration, change in heart rate). 

Importantly, the effects of the proposed 

activities are expected to be sufficiently 

low-level and localized to specific areas 

as to not meaningfully impact important 

behaviors, such as migratory behavior of 

North Atlantic right whales. These takes 

are expected to result in temporary 

behavioral reactions, such as slight 

displacement (but not abandonment) of 

migratory habitat or temporary cessation 

of feeding. 

Further, given these exposures are 

generally expected to occur to different 

individual right whales migrating 

through (i.e., most individuals would 

not be expected to be impacted on more 

than 1 day in a year), with some subset 

potentially being exposed on no more 

than a few days within the year, they are 

unlikely to result in energetic 

consequences that could affect 

reproduction or survival of any 

individuals. 

Overall, NMFS expects that any 

behavioral harassment of North Atlantic 

right whales incidental to the specified 

activities would not result in changes to 

their migration patterns or foraging 

success, as only temporary avoidance of 

an area during construction is expected 

to occur. As described previously, North 

Atlantic right whales migrating through 

the Project Area are not expected to 

remain in this habitat for extensive 

durations, and any temporarily 

displaced animals would be able to 

return to or continue to travel through 

and forage in these areas once activities 

have ceased. 

Although acoustic masking may occur 

in the vicinity of the foundation 

installation activities, based on the 

acoustic characteristics of noise 

associated with pile driving (e.g., 

frequency spectra, short duration of 

exposure) and construction surveys 

(e.g., intermittent signals), NMFS 

expects masking effects to be minimal 

(e.g., impact pile driving) to none (e.g., 

HRG surveys). In addition, masking 

would likely only occur during the 

period of time that a North Atlantic 

right whale is in the relatively close 

vicinity of pile driving, which is 

expected to be intermittent within a 

day, and confined to the months in 

which North Atlantic right whales are at 

lower densities and primarily moving 

through the area, anticipated mitigation 

effectiveness, and likely avoidance 

behaviors. TTS is another potential form 

of Level B harassment that could result 

in brief periods of slightly reduced 

hearing sensitivity affecting behavioral 

patterns by making it more difficult to 

hear or interpret acoustic cues within 

the frequency range (and slightly above) 

of sound produced during impact pile 

driving; however, any TTS would likely 

be of low amount, limited duration, and 

limited to frequencies where most 

construction noise is centered (below 2 

kHz). NMFS expects that right whale 

hearing sensitivity would return to preexposure levels shortly after migrating 

through the area or moving away from 

the sound source. 

As described in the Potential Effects 

of Specified Activities on Marine 

Mammals and Their Habitat section, the 

distance of the receiver to the source 

influences the severity of response with 

greater distances typically eliciting less 

severe responses. NMFS recognizes 

North Atlantic right whales migrating 

could be pregnant females (in the fall) 

and cows with older calves (in spring) 

and that these animals may slightly alter 

their migration course in response to 

any foundation pile driving; however, as 

described in the Potential Effects of 

Specified Activities on Marine 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
568 Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 

Mammals and Their Habitat section, we 

anticipate that course diversion would 

be of small magnitude. Hence, while 

some avoidance of the pile driving 

activities may occur, we anticipate any 

avoidance behavior of migratory North 

Atlantic right whales would be similar 

to that of gray whales (Tyack et al., 

1983), on the order of hundreds of 

meters up to 1 to 2 km. This diversion 

from a migratory path otherwise 

uninterrupted by the proposed activities 

is not expected to result in meaningful 

energetic costs that would impact 

annual rates of recruitment of survival. 

NMFS expects that North Atlantic right 

whales would be able to avoid areas 

during periods of active noise 

production while not being forced out of 

this portion of their habitat. 

North Atlantic right whale presence 

in the Project Area is year-round. 

However, abundance during summer 

months is lower compared to the winter 

months with spring and fall serving as 

‘‘shoulder seasons’’ wherein abundance 

waxes (fall) or wanes (spring). Given 

this year-round habitat usage, in 

recognition that where and when 

whales may actually occur during 

project activities is unknown as it 

depends on the annual migratory 

behaviors, US Wind has proposed, and 

NMFS is proposing in this rule, to 

require a suite of mitigation measures 

designed to reduce impacts to North 

Atlantic right whales to the maximum 

extent practicable. These mitigation 

measures (e.g., seasonal/daily work 

restrictions, vessel separation distances, 

reduced vessel speed) would not only 

avoid the likelihood of vessel strikes but 

also would minimize the severity of 

behavioral disruptions by minimizing 

impacts (e.g., through sound reduction 

using attenuation systems and reduced 

temporal overlap of project activities 

and North Atlantic right whales). This 

would further ensure that the number of 

takes by Level B harassment that are 

estimated to occur are not expected to 

affect reproductive success or 

survivorship by detrimental impacts to 

energy intake or cow/calf interactions 

during migratory transit. However, even 

in consideration of recent habitat-use 

and distribution shifts, US Wind would 

still be installing foundations when the 

presence of North Atlantic right whales 

is expected to be lower. 

As described in the Description of 

Marine Mammals in the Geographic 

Area of Specified Activities section, the 

Project would be constructed within the 

North Atlantic right whale migratory 

corridor BIA, which represent areas and 

months within which a substantial 

portion of a species or population is 

known to migrate. The area over which 

North Atlantic right whales may be 

harassed is relatively small compared to 

the width of the migratory corridor. The 

width of the migratory corridor in this 

area is approximately 163.8 km while 

the width of the Lease Area, at the 

longest point, is approximately 33.1 km. 

North Atlantic right whales may be 

displaced from their normal path and 

preferred habitat in the immediate 

activity area (primarily from pile driving 

activities), however, we do not 

anticipate displacement to be of high 

magnitude (e.g., beyond a few 

kilometers); thereby, any associated bioenergetic expenditure is anticipated to 

be small. There are no known North 

Atlantic right whale feeding, breeding, 

or calving areas within the Project Area. 

Prey species are mobile (e.g., calanoid 

copepods can initiate rapid and directed 

escape responses) and are broadly 

distributed throughout the Project Area 

(noting again that North Atlantic right 

whale prey is not particularly 

concentrated in the Project Area relative 

to nearby habitats). Therefore, any 

impacts to prey that may occur are also 

unlikely to impact marine mammals. 

The most significant measure to 

minimize impacts to individual North 

Atlantic right whales is the seasonal 

moratorium on all foundation 

installation activities from December 1 

through April 30, when North Atlantic 

right whale abundance in the Project 

Area is expected to be highest. NMFS 

also expects this measure to greatly 

reduce the potential for mother-calf 

pairs to be exposed to impact pile 

driving noise above the Level B 

harassment threshold during their 

annual spring migration through the 

Project Area from calving grounds to 

primary foraging grounds (e.g., Cape 

Cod Bay). NMFS expects that exposures 

to North Atlantic right whales would be 

reduced due to the additional proposed 

mitigation measures that would ensure 

that any exposures above the Level B 

harassment threshold would result in 

only short-term effects to individuals 

exposed. 

Pile driving may only begin in the 

absence of North Atlantic right whales 

(based on visual and passive acoustic 

monitoring). If pile driving has 

commenced, NMFS anticipates North 

Atlantic right whales would avoid the 

area, utilizing nearby waters to carry on 

pre-exposure behaviors. However, 

foundation installation activities must 

be shut down if a North Atlantic right 

whale is sighted at any distance unless 

a shutdown is not feasible due to risk of 

injury or loss of life. Shutdown may 

occur anywhere if North Atlantic right 

whales are seen within or beyond the 

Level B harassment zone, further 

minimizing the duration and intensity 

of exposure. NMFS anticipates that if 

North Atlantic right whales go 

undetected and they are exposed to 

foundation installation noise, it is 

unlikely a North Atlantic right whale 

would approach the sound source 

locations to the degree that they would 

expose themselves to very high noise 

levels. This is because typical observed 

whale behavior demonstrates likely 

avoidance of harassing levels of sound 

where possible (Richardson et al., 1985). 

These measures are designed to avoid 

PTS and also reduce the severity of 

Level B harassment, including the 

potential for TTS. While some TTS 

could occur, given the proposed 

mitigation measures (e.g., delay pile 

driving upon a sighting or acoustic 

detection and shutting down upon a 

sighting or acoustic detection), the 

potential for TTS to occur is low. 

The proposed clearance and 

shutdown measures are most effective 

when detection efficiency is maximized, 

as the measures are triggered by a 

sighting or acoustic detection. To 

maximize detection efficiency, US Wind 

proposed, and NMFS is proposing to 

require, the combination of PAM and 

visual observers. NMFS is proposing to 

require communication protocols with 

other project vessels, and other 

heightened awareness efforts (e.g., daily 

monitoring of North Atlantic right 

whale sighting databases) such that as a 

North Atlantic right whale approaches 

the source (and thereby could be 

exposed to higher noise energy levels), 

PSO detection efficacy would increase, 

the whale would be detected, and a 

delay to commencing foundation 

installation or shutdown (if feasible) 

would occur. In addition, the 

implementation of a soft-start for impact 

pile driving would provide an 

opportunity for whales to move away 

from the source if they are undetected, 

reducing received levels. 

For HRG surveys, the maximum 

distance to the Level B harassment 

threshold is 200 m. The estimated take, 

by Level B harassment only, associated 

with HRG surveys is to account for any 

North Atlantic right whale sightings 

PSOs may miss when HRG acoustic 

sources are active. However, because of 

the short maximum distance to the 

Level B harassment threshold, the 

requirement that vessels maintain a 

distance of 500 m from any North 

Atlantic right whales, the fact that 

whales are unlikely to remain in close 

proximity to an HRG survey vessel for 

any length of time, and that the acoustic 

source would be shut down if a North 

Atlantic right whale is observed within 

500 m of the source, any exposure to 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 569 

noise levels above the harassment 

threshold (if any) would be very brief. 

To further minimize exposures, rampup of sub-bottom profilers must be 

delayed during the clearance period if 

PSOs detect a North Atlantic right 

whale (or any other ESA-listed species) 

within 500 m of the acoustic source. 

With implementation of the proposed 

mitigation requirements, take by Level 

A harassment is unlikely and, therefore, 

not proposed for authorization. 

Potential impacts associated with Level 

B harassment would include low-level, 

temporary behavioral modifications, 

most likely in the form of avoidance 

behavior. Given the high level of 

precautions taken to minimize both the 

amount and intensity of Level B 

harassment on North Atlantic right 

whales, it is unlikely that the 

anticipated low-level exposures would 

lead to reduced reproductive success or 

survival. 

As described above, no serious injury 

or mortality, or Level A harassment, of 

North Atlantic right whale is anticipated 

or proposed for authorization. Extensive 

North Atlantic right whale-specific 

mitigation measures (beyond the robust 

suite required for all species) are 

expected to further minimize the 

amount and severity of Level B 

harassment. Given the documented 

habitat use within the area, the majority 

of the individuals predicted to be taken 

(including no more than ten instances of 

take, by Level B harassment only, over 

the course of the 5-year rule, with an 

annual maximum of no more than four) 

would be impacted on only 1, or maybe 

2, days in a year as North Atlantic right 

whales utilize this area for migration 

and would be transiting rather than 

residing in the area for extended periods 

of time. Further, any impacts to North 

Atlantic right whales are expected to be 

in the form of lower-level behavioral 

disturbance. 

Given the magnitude and severity of 

the impacts discussed above, and in 

consideration of the proposed 

mitigation and other information 

presented, US Wind’s activities are not 

expected to result in impacts on the 

reproduction or survival of any 

individuals, much less affect annual 

rates of recruitment or survival. For 

these reasons, we have preliminarily 

determined that the take (by Level B 

harassment only) anticipated and 

proposed for authorization would have 

a negligible impact on the North 

Atlantic right whale. 

Fin Whale 

The fin whale is listed as Endangered 

under the ESA, and the western North 

Atlantic stock is considered both 

Depleted and Strategic under the 

MMPA. No UME has been designated 

for this species or stock. No serious 

injury or mortality is anticipated or 

proposed for authorization for this 

species. 

The proposed rule would allow for 

the authorization of up to 41 takes, by 

Level A harassment and Level B 

harassment, over the 5-year period. The 

maximum annual allowable take by 

Level A harassment and Level B 

harassment, would be 2 and 18, 

respectively (combined, this annual take 

(n=20) equates to approximately 0.29 

percent of the stock abundance if each 

take were considered to be of a different 

individual). The Project Area does not 

overlap with any known areas of 

specific biological importance to fin 

whales. It is possible that some subset 

of the individual whales exposed could 

be taken several times annually. 

Level B harassment is expected to be 

in the form of behavioral disturbance, 

primarily resulting in avoidance of the 

Project Area where foundation 

installation is occurring, and some lowlevel TTS and masking that may limit 

the detection of acoustic cues for 

relatively brief periods of time. Any 

potential PTS would be minor (limited 

to a few dB) and any TTS would be of 

short duration and concentrated at onehalf or one octave above the frequency 

band of pile driving noise (most sound 

is below 2 kHz) which does not include 

the full predicted hearing range of fin 

whales. If TTS is incurred, hearing 

sensitivity would likely return to preexposure levels relatively shortly after 

exposure ends. Any masking or 

physiological responses would also be 

of low magnitude and severity for 

reasons described above. Level B 

harassment would be temporary, with 

primary impacts being temporary 

displacement of the Project Area but not 

abandonment of any migratory or 

foraging behavior. There is no known 

foraging habitat for fin whales within 

the Project Area. Any fin whales in the 

Project Area would be expected to be 

migrating through the area and would 

have sufficient space to move away from 

Project activities. 

Fin whales are frequently observed in 

the waters off of Maryland and are one 

of the most commonly detected large 

baleen whales in continental shelf 

waters, principally from Cape Hatteras 

in the Mid-Atlantic northward to Nova 

Scotia, Canada (CETAP, 1982; Hain et 

al., 1992; BOEM 2012; Barco et al., 

2015; Edwards et al., 2015; Bailey et al., 

2018; Hayes et al., 2023). Fin whales 

have high relative abundance in the 

Mid-Atlantic and Project Area, and most 

observations occur in the winter and 

early spring months (Williams et al., 

2015d; Barco et al., 2015), with larger 

group sizes occurring during the winter 

months (Barco et al., 2015). However, 

fin whales typically feed in waters off of 

New England and within the Gulf of 

Maine, areas north of the Project Area, 

as New England and Gulf of St. 

Lawrence waters represent major 

feeding ground for fin whales (Hayes et 

al., 2023). Hain et al. (1992) based on an 

analysis of neonate stranding data, 

suggested that calving takes place 

during October to January in latitudes of 

the U.S. mid-Atlantic region; however, 

it is unknown where calving, mating, 

and wintering occur for most of the 

population (Hayes et al., 2023). 

Given the documented habitat use 

within the area, some of the individuals 

taken may be exposed on multiple days. 

However, as described, the project area 

does not include areas where fin whales 

are known to concentrate for feeding or 

reproductive behaviors and the 

predicted takes are expected to be in the 

form of lower-level impacts. Given the 

magnitude and severity of the impacts 

discussed above (including no more 

than 18 takes, by Level A harassment 

and Level B harassment, over the course 

of the 5-year rule, and a maximum 

annual allowable take by Level A 

harassment and Level B harassment, of 

2 and 18 respectively), and in 

consideration of the proposed 

mitigation and other information 

presented, US Wind’s proposed 

activities are not expected to result in 

impacts on the reproduction or survival 

of any individuals, much less affect 

annual rates of recruitment or survival. 

For these reasons, we have preliminarily 

determined that the take (by Level A 

harassment and Level B harassment) 

anticipated and proposed to be 

authorized would have a negligible 

impact on the western North Atlantic 

stock of fin whales. 

Humpback Whale 

The West Indies DPS of humpback 

whales is not listed as threatened or 

endangered under the ESA, but the Gulf 

of Maine stock, which includes 

individuals from the West Indies DPS, 

is considered Strategic under the 

MMPA. However, as described in the 

Description of Marine Mammals in the 

Geographic Area of Specified Activities, 

humpback whales along the Atlantic 

Coast have been experiencing an active 

UME as elevated humpback whale 

mortalities have occurred along the 

Atlantic coast from Maine through 

Florida since January 2016. Of the cases 

examined, approximately 40 percent 

had evidence of human interaction 

(vessel strike or entanglement). The 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
570 Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 

UME does not yet provide cause for 

concern regarding population-level 

impacts and take from vessel strike and 

entanglement is not proposed to be 

authorized. Despite the UME, the 

relevant population of humpback 

whales (the West Indies breeding 

population, or DPS, of which the Gulf 

of Maine stock is a part) remains stable 

at approximately 12,000 individuals. 

The proposed rule would allow for 

the authorization of up to 36 takes, by 

Level A harassment and Level B 

harassment, over the 5-year period. The 

maximum annual allowable take by 

Level A harassment and Level B 

harassment would be 2 and 16, 

respectively (combined, this maximum 

annual take (n=18) equates to 

approximately 1.29 percent of the stock 

abundance if each take were considered 

to be of a different individual). Given 

that humpback whales are known to 

forage in areas just south of Maryland 

during the winter and could potentially 

be foraging off Maryland during this 

time as well, it is likely that some subset 

of the individual whales exposed could 

be taken several times annually. 

Among the activities analyzed, impact 

pile driving is likely to result in the 

highest amount of Level A harassment 

annual take of (n=2) humpback whales. 

The maximum amount of annual take 

proposed to be authorized (n=14), by 

Level B harassment, is highest for 

impact pile driving. 

As described in the Description of 

Marine Mammals in the Geographic 

Area of Specified Activities section, 

humpback whales are known to occur 

regularly throughout the Mid-Atlantic 

Bight, including Maryland waters, with 

strong seasonality of peak occurrences 

during winter and spring (Barco et al., 

2015; Bailey et al., 2018; Hayes et al., 

2023). 

In the western North Atlantic, 

humpback whales feed during spring, 

summer, and fall over a geographic 

range encompassing the eastern coast of 

the United States. Feeding is generally 

considered to be focused in areas north 

of the Project Area, including a feeding 

BIA in the Gulf of Maine/Stellwagen 

Bank/Great South Channel, but has been 

documented farther south and off the 

coast of Virginia. When foraging, 

humpback whales tend to remain in the 

area for extended durations to capitalize 

on the food sources. 

Assuming humpback whales who are 

feeding in waters within or surrounding 

the Project Area behave similarly, we 

expect that the predicted instances of 

disturbance could be comprised of some 

individuals that may be exposed on 

multiple days if they are utilizing the 

area as foraging habitat. Also similar to 

other baleen whales, if migrating, 

individuals would likely be exposed to 

noise levels from the project above the 

harassment thresholds only once during 

migration through the Project Area. 

For all the reasons described in the 

Mysticetes section above, we anticipate 

any potential PTS and TTS would be 

concentrated at one-half or one octave 

above the frequency band of pile driving 

noise (most sound is below 2 kHz) 

which is lower than the full predicted 

hearing range of humpback whales. If 

TTS is incurred, hearing sensitivity 

would likely return to pre-exposure 

levels relatively shortly after exposure 

ends. Any masking or physiological 

responses would also be of low 

magnitude and severity for reasons 

described above. Limited foraging 

habitat exists for humpback whales 

within the Project Area as their main 

foraging habitat is located further north. 

Any humpback whales in the Project 

Area would more likely be migrating 

through the area. 

Given the magnitude and severity of 

the impacts discussed above (including 

no more than 36 humpback whale takes 

over the course of the 5-year rule, a 

maximum annual allowable take by 

Level A harassment and Level B 

harassment, of 2 and 16, respectively), 

and in consideration of the proposed 

mitigation measures and other 

information presented, US Wind’s 

activities are not expected to result in 

impacts on the reproduction or survival 

of any individuals, much less affect 

annual rates of recruitment or survival. 

For these reasons, we have preliminarily 

determined that the take by harassment 

anticipated and proposed to be 

authorized would have a negligible 

impact on the Gulf of Maine stock of 

humpback whales. 

Minke Whale 

Minke whales are not listed under the 

ESA, and the Canadian east coast stock 

is neither considered Depleted nor 

Strategic under the MMPA. There are no 

known areas of specific biological 

importance in or adjacent to the Project 

Area. As described in the Description of 

Marine Mammals in the Geographic 

Area of Specified Activities, a UME has 

been designated for this species but is 

pending closure. No serious injury or 

mortality is anticipated or proposed for 

authorization for this species. 

The proposed rule would allow for 

the authorization of up to 67 minke 

whale takes, by Level A harassment and 

Level B harassment, over the 5-year 

period. The maximum annual allowable 

take by Level A harassment and Level 

B harassment, would be 6 and 41, 

respectively (combined, this annual take 

(n=47) equates to approximately 0.21 

percent of the stock abundance if each 

take were considered to be of a different 

individual). As described in the 

Description of Marine Mammals in the 

Geographic Area of Specified Activities 

section, minke whales are common 

offshore the U.S. eastern seaboard with 

a strong seasonal component in the 

continental shelf and in deeper, off-shelf 

waters (CETAP, 1982; Hayes et al., 

2023). In the Project Area, minke whales 

are predominantly migratory and their 

known feeding areas are north, 

including a feeding BIA in the 

southwestern Gulf of Maine and 

George’s Bank. Therefore, they would be 

more likely to be moving through (with 

each take representing a separate 

individual), though it is possible that 

some subset of the individual whales 

exposed could be taken up to a few 

times annually. 

As described in the Description of 

Marine Mammals in the Geographic 

Area of Specified Activities section, 

there is a UME for minke whales along 

the Atlantic Coast from Maine through 

South Carolina, with the highest 

number of deaths in Massachusetts, 

Maine, and New York, and preliminary 

findings in several of the whales have 

shown evidence of human interactions 

or infectious diseases. However, we note 

that the population abundance is greater 

than 21,000 and the take proposed for 

authorization through this action is not 

expected to exacerbate the UME in any 

way. 

We anticipate the impacts of this 

harassment to follow those described in 

the general Mysticetes section above. 

Any potential PTS would be minor 

(limited to a few dB) and any TTS 

would be of short duration and 

concentrated at one-half or one octave 

above the frequency band of pile driving 

noise (most sound is below 2 kHz) 

which does not include the full 

predicted hearing range of minke 

whales. If TTS is incurred, hearing 

sensitivity would likely return to preexposure levels relatively shortly after 

exposure ends. Any masking or 

physiological responses would also be 

of low magnitude and severity for 

reasons described above. Level B 

harassment would be temporary, with 

primary impacts being temporary 

displacement of the Project Area but not 

abandonment of any migratory or 

foraging behavior. Limited foraging 

habitat for minke whales exists in the 

Project Area as major foraging habitats 

are located further north near New 

England. Any minke whales in the 

Project Area would be expected to 

migrate through the area and would 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 571 

have sufficient space to move away from 

Project activities. 

Given the magnitude and severity of 

the impacts discussed above (including 

no more than 67 takes over the course 

of the 5-year rule, and a maximum 

annual allowable take by Level A 

harassment and Level B harassment, of 

6 and 41, respectively), and in 

consideration of the proposed 

mitigation measures and other 

information presented, US Wind’s 

activities are not expected to result in 

impacts on the reproduction or survival 

of any individuals, much less affect 

annual rates of recruitment or survival. 

For these reasons, we have preliminarily 

determined that the take by harassment 

anticipated and proposed to be 

authorized would have a negligible 

impact on the Canadian eastern coastal 

stock of minke whales. 

Sei Whale 

Sei whales are listed as Endangered 

under the ESA, and the Nova Scotia 

stock is considered both Depleted and 

Strategic under the MMPA. There are no 

known areas of specific biological 

importance in or adjacent to the Project 

Area and no UME has been designated 

for this species or stock. No serious 

injury or mortality is anticipated or 

proposed for authorization for this 

species. 

The proposed rule would allow for 

the authorization of up to six takes, by 

Level A harassment and Level B 

harassment, over the 5-year period. The 

maximum annual allowable take by 

Level A harassment and Level B 

harassment, would be one and one, 

respectively (combined, this annual take 

(n=2) equates to approximately 0.03 

percent of the stock abundance, if each 

take were considered to be of a different 

individual). As described in the 

Description of Marine Mammals in the 

Geographic Area of Specified Activities 

section, most of the sei whale 

distribution is concentrated in Canadian 

waters and seasonally in northerly 

United States waters, though they are 

uncommonly observed in the waters off 

of Maryland. Because sei whales are 

migratory and their known feeding areas 

are east and north of the Project Area 

(e.g., there is a feeding BIA in the Gulf 

of Maine), they would be more likely to 

be moving through and, considering this 

and the very low number of total takes, 

it is unlikely that any individual would 

be exposed more than once within a 

given year. 

With respect to the severity of those 

individual takes by behavioral Level B 

harassment, we would anticipate 

impacts to be limited to low-level, 

temporary behavioral responses with 

avoidance and potential masking 

impacts in the vicinity of the turbine 

installation to be the most likely type of 

response. Any potential PTS and TTS 

would likely be concentrated at one-half 

or one octave above the frequency band 

of pile driving noise (most sound is 

below 2 kHz) which is below the full 

predicted hearing range of sei whales. 

Moreover, any TTS would be of a small 

degree. Any avoidance of the Project 

Area due to the Project’s activities 

would be expected to be temporary. 

There is no known foraging habitat that 

exists in the Project Area for sei whales. 

Any sei whales in the Project Area 

would be expected to be migrating 

through the area. 

Given the magnitude and severity of 

the impacts discussed above (including 

no more than six takes over the course 

of the 5-year rule, and a maximum 

annual allowable take by Level A 

harassment and Level B harassment, of 

one and one, respectively), and in 

consideration of the proposed 

mitigation measures and other 

information presented, US Wind’s 

activities are not expected to result in 

impacts on the reproduction or survival 

of any individuals, much less affect 

annual rates of recruitment or survival. 

For these reasons, we have preliminarily 

determined that the take by harassment 

anticipated and proposed to be 

authorized would have a negligible 

impact on the Nova Scotia stock of sei 

whales. 

Odontocetes 

In this section, we include 

information here that applies to all of 

the odontocete species and stocks 

addressed below. Odontocetes include 

dolphins, porpoises, and all other 

whales possessing teeth, and we further 

divide them into the following 

subsections: sperm whales, small 

whales and dolphins, and harbor 

porpoise. These sub-sections include 

more specific information, as well as 

conclusions for each stock represented. 

All of the takes of odontocetes 

proposed for authorization incidental to 

US Wind’s specified activities are by 

pile driving and HRG surveys. No 

serious injury or mortality is anticipated 

or proposed. We anticipate that, given 

ranges of individuals (i.e., that some 

individuals remain within a small area 

for some period of time), and nonmigratory nature of some odontocetes in 

general (especially as compared to 

mysticetes), these takes are more likely 

to represent multiple exposures of a 

smaller number of individuals than is 

the case for mysticetes, though some 

takes may also represent one-time 

exposures to an individual. Foundation 

installation is likely to disturb 

odontocetes to the greatest extent, 

compared to HRG surveys. While we 

expect animals to avoid the area during 

foundation installation, their habitat 

range is extensive compared to the area 

ensonified during these activities. 

As described earlier, Level B 

harassment may include direct 

disruptions in behavioral patterns (e.g., 

avoidance, changes in vocalizations 

(from masking) or foraging), as well as 

those associated with stress responses or 

TTS. Odontocetes are highly mobile 

species and, similar to mysticetes, 

NMFS expects any avoidance behavior 

to be limited to the area near the sound 

source. While masking could occur 

during foundation installation, it would 

only occur in the vicinity of and during 

the duration of the activity and would 

not generally occur in a frequency range 

that overlaps most odontocete 

communication or any echolocation 

signals. The mitigation measures (e.g., 

use of sound attenuation systems, 

implementation of clearance and 

shutdown zones) would also minimize 

received levels such that the severity of 

any behavioral response would be 

expected to be less than exposure to 

unmitigated noise exposure. 

Any masking or TTS effects are 

anticipated to be of low severity. First, 

the frequency range of pile driving, the 

most impactful activity proposed to be 

conducted in terms of response severity, 

falls within a portion of the frequency 

range of most odontocete vocalizations. 

However, odontocete vocalizations span 

a much wider range than the lowfrequency construction activities 

proposed for the project. As described 

above, recent studies suggest 

odontocetes have a mechanism to selfmitigate (i.e., reduce hearing sensitivity) 

the impacts of noise exposure, which 

could potentially reduce TTS impacts. 

Any masking or TTS is anticipated to be 

limited and would typically only 

interfere with communication within a 

portion of an odontocete’s range and as 

discussed earlier, the effects would only 

be expected to be of a short duration 

and, for TTS, a relatively small degree. 

Furthermore, odontocete echolocation 

occurs predominantly at frequencies 

significantly higher than low-frequency 

construction activities. Therefore, there 

is little likelihood that threshold shift 

would interfere with feeding behaviors. 

For HRG surveys, the sources operate at 

higher frequencies than foundation 

installation activities. However, sounds 

from these sources attenuate very 

quickly in the water column, as 

described above. Therefore, any 

potential for PTS and TTS and masking 

is very limited. Further, odontocetes 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
572 Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 

(e.g., common dolphins, spotted 

dolphins, bottlenose dolphins) have 

demonstrated an affinity to bow-ride 

actively surveying HRG surveys. 

Therefore, the severity of any 

harassment during HRG surveys, if it 

does occur, is anticipated to be very low 

in severity based on the lack of 

avoidance previously demonstrated by 

these species. 

The waters off the coast of Maryland 

are used by several odontocete species. 

None of these species are listed under 

the ESA, and there are no known 

habitats of particular importance. In 

general, odontocete habitat ranges are 

far-reaching along the Atlantic coast of 

the United States, and the waters off of 

Maryland, including the Project Area, 

do not contain any unique odontocete 

habitat features. 

Dolphins and Small Whales (Including 

Delphinids) 

The 10 species and 11 stocks included 

in this group for which NMFS is 

proposing to authorize take are not 

listed under the ESA; however, shortfinned pilot whales are listed as 

Strategic under the MMPA. There are no 

known areas of specific biological 

importance in or around the Project 

Area for any of these species and no 

UMEs have been designated for any of 

these species. No serious injury, 

mortality, or take by Level A harassment 

is anticipated or proposed for 

authorization for these species. 

The 10 delphinid species for which 

NMFS proposes to authorize take are: 

Atlantic spotted dolphin, Pantropical 

spotted dolphin, common bottlenose 

dolphin (coastal and northern migratory 

stocks), common dolphin, long-finned 

pilot whale, short-finned pilot whale, 

killer whale, rough-toothed dolphin, 

striped dolphin, and Risso’s dolphin. 

The proposed rule would allow for the 

authorization of up to between 3 and 

3,013 takes (depending on species), by 

Level B harassment only, over the 5-year 

period. The maximum annual allowable 

take for these species by Level B 

harassment, would range from 3 to 

1,762, respectively (this annual take 

equates to approximately 0.07 to 24.0 

percent of the stock abundance, 

depending on each species, if each take 

were considered to be of a different 

individual). 

For both stocks of bottlenose 

dolphins, given the comparatively 

higher number of total annual takes 

(1,591 for coastal and 1,768 for offshore) 

and the relative number of takes as 

compared to the stock abundance (24.0 

and 2.81, respectively), primarily due to 

the progression of the location of impact 

pile driving each year, while some of 

the takes likely represent exposures of 

different individuals on 1 day a year, it 

is likely that some subset of the 

individuals exposed could be taken 

several times annually. For Atlantic 

spotted dolphins, Pantropical spotted 

dolphins, common dolphins, long- and 

short-finned pilot whales, killer whales, 

rough-toothed dolphins, striped 

dolphins, and Risso’s dolphins, given 

the number of takes, while many of the 

takes likely represent exposures of 

different individuals on 1 day a year, 

some subset of the individuals exposed 

could be taken up to a few times 

annually. 

Dolphins and small delphinids engage 

in social, reproductive, and foraging 

behavior in the waters offshore of 

Maryland. However, the number of 

takes, likely movement patterns of the 

affected species, and the intensity of any 

Level B harassment, combined with the 

availability of alternate nearby habitat 

that supports the aforementioned 

behaviors suggests that the likely 

impacts would not impact the 

reproduction or survival of any 

individuals. While delphinids may be 

taken on several occasions, none of 

these species are known to have small 

home ranges within the Project Area or 

known to be particularly sensitive to 

anthropogenic noise. No Level A 

harassment (PTS) is anticipated or 

proposed to be authorized. Some TTS 

could occur, but it would be limited to 

the frequency ranges of the activity and 

any loss of hearing sensitivity is 

anticipated to return to pre-exposure 

conditions shortly after the animals 

move away from the source or the 

source ceases. 

Given the magnitude and severity of 

the impacts discussed above, and in 

consideration of the proposed 

mitigation and other information 

presented, US Wind’s activities are not 

expected to result in impacts on the 

reproduction or survival of any 

individuals, much less affect annual 

rates of recruitment or survival. For 

these reasons, we have preliminarily 

determined that the take by harassment 

anticipated and proposed for 

authorization would have a negligible 

impact on all of the species and stocks 

addressed in this section. 

Harbor Porpoise 

Harbor porpoises are not listed as 

Threatened or Endangered under the 

ESA, and the Gulf of Maine/Bay of 

Fundy stock is neither considered 

Depleted or Strategic under the MMPA. 

The stock is found predominantly in 

northern U.S. coastal waters (less than 

150 m depth) and up into Canada’s Bay 

of Fundy (between New Brunswick and 

Nova Scotia). Although the population 

trend is not known, there are no UMEs 

or other factors that cause particular 

concern for this stock. No mortality or 

non-auditory injury are anticipated or 

proposed for authorization for this 

stock. 

The proposed rule would allow for 

the authorization of up to 74 takes, by 

Level A harassment and Level B 

harassment, over the 5-year period. The 

maximum annual allowable take by 

Level A harassment and Level B 

harassment, would be 3 and 39, 

respectively (combined, this annual take 

(n=42) equates to approximately 0.04 

percent of the stock abundance if each 

take were considered to be of a different 

individual). Given the number of takes, 

many of the takes likely represent 

exposures of different individuals on 1 

day a year. 

Regarding the severity of takes by 

Level B harassment, because harbor 

porpoises are particularly sensitive to 

noise, it is likely that a fair number of 

the responses could be of a moderate 

nature, particularly to pile driving. In 

response to pile driving, harbor 

porpoises are likely to avoid the area 

during construction, as previously 

demonstrated in Tougaard et al. (2009) 

in Denmark, in Dahne et al. (2013) in 

Germany, and in Vallejo et al. (2017) in 

the United Kingdom, although a study 

by Graham et al. (2019) may indicate 

that the avoidance distance could 

decrease over time. Given that 

foundation installation is scheduled to 

occur off the coast of Maryland and, 

given alternative foraging areas nearby, 

any avoidance of the area by individuals 

is not likely to impact the reproduction 

or survival of any individuals. 

With respect to PTS and TTS, the 

effects on an individual are likely 

relatively low given the frequency bands 

of pile driving (most energy below 2 

kHz) compared to harbor porpoise 

hearing (150 Hz to 160 kHz peaking 

around 40 kHz). Specifically, TTS is 

unlikely to impact hearing ability in 

their more sensitive hearing ranges, or 

the frequencies in which they 

communicate and echolocate. We 

expect any PTS that may occur to be 

within the very low end of their hearing 

range where harbor porpoises are not 

particularly sensitive, and any PTS 

would affect a relatively small portion 

of the individual’s hearing range. As 

such, any PTS would not interfere with 

key foraging or reproductive strategies 

necessary for reproduction or survival. 

Harbor porpoises are seasonally 

distributed (Hayes et al., 2023). During 

fall (October through December) and 

spring (April through June), harbor 

porpoises are widely dispersed from 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 573 

New Jersey to Maine, with lower 

densities farther north and south. 

During winter (January to March), 

intermediate densities of harbor 

porpoises can be found in waters off 

New Jersey to North Carolina, and lower 

densities are found in waters off New 

York to New Brunswick, Canada. In 

non-summer months they have been 

seen from the coastline to deep waters 

(>1,800 m; Westgate et al., 1998), 

although the majority are found over the 

continental shelf. While harbor 

porpoises are likely to avoid the area 

during any of the project’s construction 

activities, as demonstrated during 

European wind farm construction, the 

time of year in which work would occur 

is when harbor porpoises are not in 

highest abundance, and any work that 

does occur would not result in the 

species’ abandonment of the waters off 

of Maryland. 

Given the magnitude and severity of 

the impacts discussed above, and in 

consideration of the proposed 

mitigation and other information 

presented, US Wind’s activities are not 

expected to result in impacts on the 

reproduction or survival of any 

individuals, much less affect annual 

rates of recruitment or survival. For 

these reasons, we have preliminarily 

determined that the take by harassment 

anticipated and proposed for 

authorization would have a negligible 

impact on the Gulf of Maine/Bay of 

Fundy stock of harbor porpoises. 

Phocids (Harbor Seals, Gray Seals, and 

Harp Seals) 

The harbor seal, gray seal, and harp 

seal are not listed under the ESA, and 

these stocks are not considered Depleted 

or Strategic under the MMPA. There are 

no known areas of specific biological 

importance in or around the Project 

Area. As described in the Description of 

Marine Mammals in the Geographic 

Area of Specified Activities section, a 

UME has been designated for harbor 

seals and gray seals and is described 

further below. No serious injury or 

mortality is anticipated or proposed for 

authorization for any seal species. 

As limited occurrence data for seals 

are available for the Project Area, take 

estimates for harbor seals, gray seals, 

and harp seals are presented as one 

estimate. For the three seal species, the 

proposed rule would allow for the total 

authorization of up to 496 seals by Level 

B harassment, over the 5-year period. 

The maximum annual allowable take for 

these species, by Level B harassment, 

would be 341 seals. If all of the 

allocated take was attributed to gray 

seals, this take would equate to 1.25 

percent of the gray seal stock 

abundance, if each take were considered 

to be of a different individual. If all of 

the allocated take was attributed to 

harbor seals, this take would equate to 

0.56 percent of the harbor seal stock 

abundance, if each take were considered 

to be of a different individual. If all of 

the allocated take was attributed to harp 

seals, this take would equate to 0.004 

percent of the harp seal stock 

abundance. Gray seals, harbor seals, and 

harp seals are considered migratory and 

none of these species have specific 

feeding areas that have been designated 

in the area, therefore, it is likely that 

takes of seals would represent exposures 

of different individuals throughout the 

project duration. 

Harp seals are considered extralimital 

in the Project Area, however, harp seal 

strandings have been documented in 

Maryland during the winter and spring 

(Hayes et al., 2023; NAB, 2023a; NAB, 

2023b). Harbor and gray seals occur in 

Maryland waters most often from late 

winter to early spring, with harbor seal 

occurrences being more common than 

gray seals (Hayes et al., 2023). Seals are 

more likely to be close to shore (e.g., 

closer to the edge of the area ensonified 

above NMFS’ harassment threshold), 

such that exposure to foundation 

installation and HRG surveys would be 

expected to be at comparatively lower 

levels. Although a gray seal rookery may 

occur off the coast of Cape Henlopen, 

north of the Project Area, based on the 

distance of this area from the Project 

Area it is not expected that in-air 

sounds produced would cause the take 

of hauled out pinnipeds. As this is the 

closest documented pinniped haul-out 

to the Project Area, NMFS does not 

expect any harassment to occur, nor 

have we proposed to authorize any take 

from in-air impacts on hauled out seals. 

As described in the Potential Effects 

of Specified Activities on Marine 

Mammals and Their Habitat section, 

construction of wind farms in Europe 

resulted in pinnipeds temporarily 

avoiding construction areas but 

returning within short time frames after 

construction was complete (Carroll et 

al., 2010; Hamre et al., 2011; Hastie et 

al., 2015; Russell et al., 2016; Brasseur 

et al., 2010). Effects on pinnipeds that 

are taken by Level B harassment in the 

Project Area would likely be limited to 

reactions such as increased swimming 

speeds, increased surfacing time, or 

decreased foraging (if such activity were 

occurring). Most likely, individuals 

would simply move away from the 

sound source and be temporarily 

displaced from those areas (Lucke et al., 

2006; Edren et al., 2010; Skeate et al., 

2012; Russell et al., 2016). Given the 

low anticipated magnitude of impacts 

from any given exposure (e.g., 

temporary avoidance), even potential 

repeated Level B harassment across a 

few days of some small subset of 

individuals, which could occur, is 

unlikely to result in impacts on the 

reproduction or survival of any 

individuals. Moreover, pinnipeds would 

benefit from the mitigation measures 

described in 50 CFR part 217— 

Regulations Governing the Taking and 

Importing of Marine Mammals 

Incidental to Specified Activities. 

As described above, noise from pile 

driving is mainly low-frequency and, 

while any TTS that does occur would 

fall within the lower end of pinniped 

hearing ranges (50 Hz to 86 kHz), TTS 

would not occur at frequencies around 

5 kHz, where pinniped hearing is most 

susceptible to noise-induced hearing 

loss (Kastelein et al., 2018). No Level A 

harassment (PTS) is anticipated or 

proposed to be authorized. In summary, 

any TTS would be of small degree and 

not occur across the entire, or even most 

sensitive, hearing range. Hence, any 

impacts from TTS are likely to be of low 

severity and not interfere with behaviors 

critical to reproduction or survival. 

Elevated numbers of harbor seal and 

gray seal mortalities were first observed 

in July 2018 and occurred across Maine, 

New Hampshire, and Massachusetts 

until 2020. Based on tests conducted so 

far, the main pathogen found in the 

seals belonging to that UME was 

phocine distemper virus, although 

additional testing to identify other 

factors that may be involved in this 

UME are underway. Currently, the only 

active UME is occurring in Maine with 

some harbor and gray seals testing 

positive for highly pathogenic avian 

influenza (HPAI) H5N1. Although 

elevated strandings continue, neither 

UME (alone or in combination) provides 

cause for concern regarding populationlevel impacts to any of these stocks. For 

harbor seals, the population abundance 

is over 61,000 and annual mortality/ 

serious injury (M/SI) (n=339) is well 

below PBR (1,729) (Hayes et al., 2023). 

The population abundance for gray seals 

in the United States is over 27,000, with 

an estimated overall abundance, 

including seals in Canada, of 

approximately 450,000. In addition, the 

abundance of gray seals is likely 

increasing in the U.S. Atlantic, as well 

as in Canada (Hayes et al., 2023). 

Given the magnitude and severity of 

the impacts discussed above, and in 

consideration of the proposed 

mitigation and other information 

presented, US Wind’s activities are not 

expected to result in impacts on the 

reproduction or survival of any 

individuals, much less affect annual 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
574 Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 

rates of recruitment or survival. For 

these reasons, we have preliminarily 

determined that the take by harassment 

anticipated and proposed for 

authorization would have a negligible 

impact on harbor, gray, and harp seals. 

Preliminary Negligible Impact 

Determination 

No mortality or serious injury is 

anticipated to occur or proposed to be 

authorized. As described in the 

preliminary analysis above, the impacts 

resulting from the project’s activities 

cannot be reasonably expected to, and 

are not reasonably likely to, adversely 

affect any of the species or stocks for 

which take is proposed for authorization 

through effects on annual rates of 

recruitment or survival. Based on the 

analysis contained herein of the likely 

effects of the specified activity on 

marine mammals and their habitat and 

taking into consideration the 

implementation of the proposed 

mitigation and monitoring measures, 

NMFS preliminarily finds that the 

marine mammal take from all of US 

Wind’s specified activities combined 

will have a negligible impact on all 

affected marine mammal species or 

stocks. 

Small Numbers 

As noted above, only small numbers 

of incidental take may be authorized 

under sections 101(a)(5)(A) and (D) of 

the MMPA for specified activities other 

than military readiness activities. The 

MMPA does not define small numbers 

and so, in practice, where estimated 

numbers are available, NMFS compares 

the number of individuals estimated to 

be taken to the most appropriate 

estimation of abundance of the relevant 

species or stock in our determination of 

whether an authorization is limited to 

small numbers of marine mammals. 

When the predicted number of 

individuals to be taken is less than onethird of the species or stock abundance, 

the take is considered to be of small 

numbers. Additionally, other qualitative 

factors may be considered in the 

analysis, such as the temporal or spatial 

scale of the activities. 

NMFS proposes to authorize 

incidental take (by Level A harassment 

and/or Level B harassment) of 19 

species of marine mammal (with 20 

managed stocks). The maximum number 

of instances of takes by combined Level 

A harassment and Level B harassment 

possible within any one year and 

proposed for authorization relative to 

the best available population abundance 

is less than one-third for all species and 

stocks potentially impacted. 

For 13 of these species (13 stocks), 

less than 1 percent of the stock 

abundance is proposed to be authorized 

for take by Level A and/or Level B 

harassment. For five stocks, less than 5 

percent is proposed, and for one stock 

less than 25 percent is proposed (coastal 

stock of bottlenose dolphins), assuming 

that each instance of take represents a 

different individual. Specific to the 

North Atlantic right whale, the 

maximum amount of take in any given 

year, which is by Level B harassment 

only, is four, or 1.18 percent of the stock 

abundance, assuming that each instance 

of take represents a different individual. 

Please see table 25 for information 

relating to this small numbers analysis. 

Based on the analysis contained 

herein of the proposed activities 

(including the proposed mitigation and 

monitoring measures) and the 

anticipated take of marine mammals, 

NMFS preliminarily finds that small 

numbers of marine mammals would be 

taken relative to the population size of 

the affected species or stocks. 

Unmitigable Adverse Impact Analysis 

and Determination 

There are no relevant subsistence uses 

of the affected marine mammal stocks or 

species implicated by this action. 

Therefore, NMFS has determined that 

the total taking of affected species or 

stocks would not have an unmitigable 

adverse impact on the availability of 

such species or stocks for taking for 

subsistence purposes. 

Classification 

Endangered Species Act (ESA) 

Section 7(a)(2) of the Endangered 

Species Act of 1973 (16 U.S.C. 1531 et 

seq.) requires that each Federal agency 

ensure that any action it authorizes, 

funds, or carries out is not likely to 

jeopardize the continued existence of 

any endangered or threatened species or 

result in the destruction or adverse 

modification of designated critical 

habitat. To ensure ESA compliance for 

the promulgation of rulemakings, NMFS 

consults internally whenever we 

propose to authorize take for 

endangered or threatened species, in 

this case with the NOAA GARFO. 

The NMFS Office of Protected 

Resources is proposing to authorize the 

take of three marine mammal species 

which are listed under the ESA: North 

Atlantic right, fin, and sei whales. The 

Permit and Conservation Division 

requested initiation of section 7 

consultation on December 5, 2023, with 

GARFO for the promulgation of the 

rulemaking. NMFS will conclude the 

ESA consultation prior to reaching a 

determination regarding the proposed 

issuance of the authorization. The 

proposed regulations and any 

subsequent LOA(s) would be 

conditioned such that, in addition to 

measures included in those documents, 

US Wind would also be required to 

abide by the reasonable and prudent 

measures and terms and conditions of 

the Biological Opinion and Incidental 

Take Statement, as issued by NMFS, 

pursuant to section 7 of the ESA. 

Executive Order 12866 

The Office of Management and Budget 

has determined that this proposed rule 

is not significant for purposes of 

Executive Order 12866. 

Regulatory Flexibility Act (RFA) 

Pursuant to the RFA (5 U.S.C. 601 et 

seq.), the Chief Counsel for Regulation 

of the Department of Commerce has 

certified to the Chief Counsel for 

Advocacy of the Small Business 

Administration that this proposed rule, 

if adopted, would not have a significant 

economic impact on a substantial 

number of small entities. US Wind is 

the sole entity that would be subject to 

the requirements in these proposed 

regulations, and US Wind is not a small 

governmental jurisdiction, small 

organization, or small business, as 

defined by the RFA. Because of this 

certification, a regulatory flexibility 

analysis is not required and none has 

been prepared. 

Paperwork Reduction Act (PRA) 

Notwithstanding any other provision 

of law, no person is required to respond 

to, nor shall a person be subject to a 

penalty for failure to comply with, a 

collection of information subject to the 

requirements of the PRA unless that 

collection of information displays a 

currently valid Office of Management 

and Budget (OMB) control number. 

These requirements have been approved 

by OMB under control number 0648– 

0151 and include applications for 

regulations, subsequent LOA, and 

reports. Send comments regarding any 

aspect of this data collection, including 

suggestions for reducing the burden, to 

NMFS. 

Coastal Zone Management Act (CZMA) 

The CZMA requires Federal actions 

within and outside the coastal zone that 

have reasonably foreseeable effects on 

any coastal use or natural resource of 

the coastal zone be consistent with the 

enforceable policies of a state’s federally 

approved coastal management program 

(16 U.S.C. 1456(c)). NMFS has 

determined that US Wind’s application 

for incidental take regulations is not an 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 575 

activity listed by the MD DNR pursuant 

to 15 CFR 930.53 and, thus, is not 

subject to Federal consistency 

requirements in the absence of the 

receipt and prior approval of an unlisted 

activity review request from the State by 

the Director of NOAA’s Office for 

Coastal Management. Consistent with 15 

CFR 930.54, NMFS published Notice of 

Receipt of US Wind’s application for 

this incidental take regulation in the 

Federal Register on May 2, 2023 (88 FR 

27453) and is now publishing the 

proposed rule. The State of Maryland 

did not request approval from the 

Director of NOAA’s Office for Coastal 

Management to review US Wind’s 

application as an unlisted activity, and 

the time period for making such request 

has expired. Therefore, NMFS has 

determined the incidental take 

authorization is not subject to Federal 

consistency review. 

Proposed Promulgation 

As a result of these preliminary 

determinations, NMFS proposes to 

promulgate an LOA to US Wind 

authorizing take, by Level A harassment 

and Level B harassment, incidental to 

construction activities associated with 

the Maryland Offshore Wind Project 

offshore of Maryland for a 5-year period 

from January 1, 2025, through December 

31, 2029, provided the previously 

mentioned mitigation, monitoring, and 

reporting requirements are incorporated. 

Request for Additional Information and 

Public Comments 

NMFS requests interested persons to 

submit comments, information, and 

suggestions concerning US Wind’s 

request and the proposed regulations 

(see ADDRESSES). All comments will be 

reviewed and evaluated as we prepare 

the final rule and make final 

determinations on whether to issue the 

requested authorization. This proposed 

rule and referenced documents provide 

all environmental information relating 

to our proposed action for public 

review. 

Recognizing, as a general matter, that 

this action is one of many current and 

future wind energy actions, we invite 

comment on the relative merits of the 

IHA, single-action rule/LOA, and 

programmatic multi-action rule/LOA 

approaches, including potential marine 

mammal take impacts resulting from 

this and other related wind energy 

actions and possible benefits resulting 

from regulatory certainty and efficiency. 

List of Subjects in 50 CFR Part 217 

Administrative practice and 

procedure, Endangered and threatened 

species, Fish, Fisheries, Marine 

mammals, Penalties, Reporting and 

recordkeeping requirements, Wildlife. 

Dated: December 6, 2023. 

Samuel D. Rauch III, 

Deputy Assistant Administrator for 

Regulatory Programs, National Marine 

Fisheries Service. 

For reasons set forth in the preamble, 

NMFS proposes to amend 50 CFR part 

217 to read as follows: 

PART 217—REGULATIONS 

GOVERNING THE TAKING AND 

IMPORTING OF MARINE MAMMALS 

INCIDENTAL TO SPECIFIED 

ACTIVITIES 

■ 1. The authority citation for part 217 

continues to read as follows: 

Authority: 16 U.S.C. 1361 et seq., unless 

otherwise noted. 

■ 2. Add subpart II, consisting of 

§§ 217.340 through 217.349, to read as 

follows: 

Subpart II—Taking Marine Mammals 

Incidental to the Maryland Offshore Wind 

Project Offshore of Maryland 

Sec. 

217.340 Specified activity and specified 

geographical region. 

217.341 Effective dates. 

217.342 Permissible methods of taking. 

217.343 Prohibitions. 

217.344 Mitigation requirements. 

217.345 Monitoring and reporting 

requirements. 

217.346 Letter of Authorization. 

217.347 Modifications of Letter of 

Authorization. 

217.348–217.349 [Reserved] 

Subpart II—Taking Marine Mammals 

Incidental to the Maryland Offshore 

Wind Project Offshore of Maryland 

§ 217.340 Specified activity and specified 

geographical region. 

(a) Regulations in this subpart apply 

to activities associated with the 

Maryland Offshore Wind Project 

(hereafter referred to as the ‘‘Project’’) by 

US Wind, Inc. (hereafter referred to as 

‘‘LOA Holder’’), and those persons it 

authorizes or funds to conduct activities 

on its behalf in the area outlined in 

paragraph (b) of this section. 

Requirements imposed on LOA Holder 

must be implemented by those persons 

it authorizes or funds to conduct 

activities on its behalf. 

(b) The specified geographical region 

is the Mid-Atlantic Bight, which 

includes, but is not limited to, the 

Bureau of Ocean Energy Management 

(BOEM) Lease Area Outer Continental 

Shelf (OCS)-A 0490 Commercial Lease 

of Submerged Lands for Renewable 

Energy Development, along the relevant 

Export Cable Corridors (ECCs), and at 

the sea-to-shore transition points 

located within Delaware Seashore State 

Park. 

(c) The specified activities are impact 

pile driving of wind turbine generator 

(WTG), offshore substation (OSS), and a 

meteorological tower (Met tower) 

foundations; high-resolution 

geophysical (HRG) site characterization 

surveys; vessel transit within the 

specified geographical region to 

transport crew, supplies, and materials; 

WTG and OSS operation; fishery and 

ecological monitoring surveys; 

placement of scour protection; and 

trenching, laying, and cable burial 

activities. 

§ 217.341 Effective dates. 

The regulations in this subpart are 

effective from January 1, 2025, through 

December 31, 2029. 

§ 217.342 Permissible methods of taking. 

Under the LOA, issued pursuant to 

§§ 216.106 of this chapter and 217.346, 

the LOA Holder, and those persons it 

authorizes or funds to conduct activities 

on its behalf, may incidentally, but not 

intentionally, take marine mammals 

within the vicinity of BOEM Lease Area 

OCS–A 0490 Commercial Lease of 

Submerged Lands for Renewable Energy 

Development, provided the LOA Holder 

is in complete compliance with all 

terms, conditions, and requirements of 

the regulations in this subpart and the 

appropriate LOA: 

(a) By Level B harassment associated 

with the acoustic disturbance of marine 

mammals by impact pile driving (WTG, 

OSS, and Met tower foundation 

installation) and HRG site 

characterization surveys; 

(b) By Level A harassment associated 

with the acoustic disturbance of marine 

mammals by impact pile driving of 

WTG foundations; 

(c) Take by mortality or serious injury 

of any marine mammal species is not 

authorized; and 

(d) The incidental take of marine 

mammals by the activities listed in 

paragraphs (a) and (b) of this section is 

limited to the following species: 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
576 Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 

TABLE 1 TO PARAGRAPH (d) 

Marine mammal species Scientific name Stock 

North Atlantic right whale ................................... Eubalaena glacialis .......................................... Western Atlantic. 

Fin whale ............................................................ Balaenoptera physalus .................................... Western North Atlantic. 

Humpback whale ................................................ Megaptera novaeangliae ................................. Gulf of Maine. 

Minke whale ....................................................... Balaenoptera acutorostrata .............................. Canadian Eastern Coastal. 

Sei whale ............................................................ Balaenoptera borealis ...................................... Nova Scotia. 

Killer whale ......................................................... Orcinus orca ..................................................... Western North Atlantic. 

Atlantic spotted dolphin ...................................... Stenella frontalis .............................................. Western North Atlantic. 

Pantropical spotted dolphin ................................ Stenella attenuata ............................................ Western North Atlantic. 

Bottlenose dolphin .............................................. Tursiops truncatus ........................................... Western North Atlantic—Offshore. 

Northern Migratory Coastal. 

Common dolphin ................................................ Delphinus delphis ............................................. Western North Atlantic. 

Long-finned pilot whale ...................................... Globicephala melas ......................................... Western North Atlantic. 

Short-finned pilot whale ...................................... Globicephala macrorhynchus .......................... Western North Atlantic. 

Risso’s dolphin ................................................... Grampus griseus .............................................. Western North Atlantic. 

Rough-toothed dolphin ....................................... Steno bredanensis ........................................... Western North Atlantic. 

Striped dolphin ................................................... Stenella coeruleoalba ...................................... Western North Atlantic. 

Harbor porpoise .................................................. Phocoena phocoena ........................................ Gulf of Maine/Bay of Fundy. 

Gray seal ............................................................ Halichoerus grypus .......................................... Western North Atlantic. 

Harbor seal ......................................................... Phoca vitulina ................................................... Western North Atlantic. 

Harp seal ............................................................ Pagophilus groenlandicus ................................ Western North Atlantic. 

§ 217.343 Prohibitions. 

Except for the takings described in 

§ 217.342 and authorized by the LOA 

issued under this subpart, it is unlawful 

for any person to do any of the 

following in connection with the 

activities described in this subpart: 

(a) Violate, or fail to comply with, the 

terms, conditions, and requirements of 

this subpart or the LOA issued under 

this subpart; 

(b) Take any marine mammal not 

specified in § 217.342(d); 

(c) Take any marine mammal 

specified in the LOA in any manner 

other than as specified in the LOA; or 

(d) Take any marine mammal 

specified in § 217.342(d), after NMFS 

Office of Protected Resources 

determines such taking results in more 

than a negligible impact on the species 

or stocks of such marine mammals. 

§ 217.344 Mitigation requirements. 

When conducting the activities 

identified in § 217.340(c) within the 

area described in § 217.340(b), LOA 

Holder must implement the mitigation 

measures contained in this section and 

any LOA issued under §§ 217.346 and 

217.347. These mitigation measures 

include, but are not limited to: 

(a) General conditions. LOA Holder 

must comply with the following general 

measures: 

(1) A copy of any issued LOA must be 

in the possession of LOA Holder and its 

designees, all vessel operators, visual 

protected species observers (PSOs), 

passive acoustic monitoring (PAM) 

operators, pile driver operators, and any 

other relevant designees operating 

under the authority of the issued LOA; 

(2) LOA Holder must conduct training 

for construction, survey, and vessel 

personnel and the marine mammal 

monitoring team (PSO and PAM 

operators) prior to the start of all inwater construction activities in order to 

explain responsibilities, communication 

procedures, marine mammal detection 

and identification, mitigation, 

monitoring, and reporting requirements, 

safety and operational procedures, and 

authorities of the marine mammal 

monitoring team(s). This training must 

be repeated for new personnel who join 

the work during the project. A 

description of the training program must 

be provided to NMFS at least 60 days 

prior to the initial training before inwater activities begin. Confirmation of 

all required training must be 

documented on a training course log 

sheet and reported to NMFS Office of 

Protected Resources prior to initiating 

project activities; 

(3) Prior to and when conducting any 

in-water activities and vessel 

operations, LOA Holder personnel and 

contractors (e.g., vessel operators, PSOs) 

must use available sources of 

information on North Atlantic right 

whale presence in or near the Project 

Area including daily monitoring of the 

Right Whale Sightings Advisory System, 

and monitoring of U.S. Coast Guard 

VHF Channel 16 throughout the day to 

receive notification of any sightings 

and/or information associated with any 

Slow Zones (i.e., Dynamic Management 

Areas (DMAs) and/or acousticallytriggered slow zones) to provide 

situational awareness for both vessel 

operators, PSO(s), and PAM operator(s); 

The marine mammal monitoring team 

must monitor these systems no less than 

every 4 hours; 

(4) Any marine mammal observed by 

project personnel must be immediately 

communicated to any on-duty PSOs, 

PAM operator(s), and all vessel 

captains. Any large whale observation 

or acoustic detection by PSOs or PAM 

operators must be conveyed to all vessel 

captains; 

(5) For North Atlantic right whales, 

any visual detection or acoustic 

detection within the PAM monitoring 

zone must trigger a delay to the 

commencement of pile driving. Any 

visual detection within 500 m must 

trigger a delay to the commencement of 

HRG surveys; 

(6) In the event that a large whale is 

sighted or acoustically detected that 

cannot be confirmed as a non-North 

Atlantic right whale, it must be treated 

as if it were a North Atlantic right whale 

for purposes of mitigation; 

(7) If a delay to commencing an 

activity is called for by the Lead PSO or 

PAM operator, LOA Holder must take 

the required mitigative action. If a delay 

or shutdown of an activity is called for 

by the Lead PSO or PAM operator, LOA 

Holder must take the required mitigative 

action unless shutdown would result in 

imminent risk of injury or loss of life to 

an individual, pile refusal, or pile 

instability. Any disagreements between 

the Lead PSO, PAM operator, and the 

activity operator regarding delays or 

shutdowns would only be discussed 

after the mitigative action has occurred; 

(8) If an individual from a species for 

which authorization has not been 

granted, or a species for which 

authorization has been granted but the 

authorized take number has been met, is 

observed entering or within the relevant 

Level B harassment zone prior to 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 577 

beginning a specified activity, the 

activity must be delayed. If the activity 

is ongoing, it must be shut down 

immediately, unless shutdown would 

result in imminent risk of injury or loss 

of life to an individual, pile refusal, or 

pile instability. The activity must not 

commence or resume until the animal(s) 

has been confirmed to have left and is 

on a path away from the Level B 

harassment zone or after 15 minutes for 

small odontocetes and pinnipeds, and 

30 minutes for all other species with no 

further sightings; 

(9) For in-water construction heavy 

machinery activities listed in 

§ 217.340(c), if a marine mammal is on 

a path towards or comes within 10 

meters (m) (32.8 feet (ft)) of equipment, 

LOA Holder must cease operations until 

the marine mammal has moved more 

than 10 m on a path away from the 

activity to avoid direct interaction with 

equipment; 

(10) All vessels must be equipped 

with a properly installed, operational 

Automatic Identification System (AIS) 

device and LOA Holder must report all 

Maritime Mobile Service Identity 

(MMSI) numbers to NMFS Office of 

Protected Resources; 

(11) By accepting the issued LOA, 

LOA Holder consents to on-site 

observation and inspections by Federal 

agency personnel (including NOAA 

personnel) during activities described in 

this subpart, for the purposes of 

evaluating the implementation and 

effectiveness of measures contained 

within the LOA and this subpart; 

(12) It is prohibited to assault, harm, 

harass (including sexually harass), 

oppose, impede, intimidate, impair, or 

in any way influence or interfere with 

a PSO, PAM Operator, or vessel crew 

member acting as an observer, or 

attempt the same. This prohibition 

includes, but is not limited to, any 

action that interferes with an observer’s 

responsibilities, or that creates an 

intimidating, hostile, or offensive 

environment. Personnel may report any 

violations to the NMFS Office of Law 

Enforcement; and 

(13) The LOA Holder must also abide 

by the reasonable and prudent measures 

and terms and conditions of the 

Biological Opinion and Incidental Take 

Statement, as issued by NMFS, pursuant 

to section 7 of the Endangered Species 

Act. 

(b) Vessel strike avoidance measures. 

LOA Holder must comply with the 

following vessel strike avoidance 

measures, unless a situation presents a 

threat to the health, safety, or life of a 

person or when a vessel, actively 

engaged in emergency rescue or 

response duties, including vessel-indistress or environmental crisis 

response, requires speeds in excess of 

10 kn to fulfill those responsibilities, 

while in the specified geographical 

region: 

(1) Prior to the start of the Project’s 

activities involving vessels, all vessel 

personnel must receive a protected 

species training that covers, at a 

minimum, identification of marine 

mammals that have the potential to 

occur where vessels would be operating; 

detection observation methods in both 

good weather conditions (i.e., clear 

visibility, low winds, low sea states) and 

bad weather conditions (i.e., fog, high 

winds, high sea states, with glare); 

sighting communication protocols; all 

vessel speed and approach limit 

mitigation requirements (e.g., vessel 

strike avoidance measures); and 

information and resources available to 

the project personnel regarding the 

applicability of Federal laws and 

regulations for protected species. This 

training must be repeated for any new 

vessel personnel who join the Project. 

Confirmation of the observers’ training 

and understanding of the Incidental 

Take Authorization (ITA) requirements 

must be documented on a training 

course log sheet and reported to NMFS; 

(2) LOA Holder, regardless of their 

vessel’s size, must maintain a vigilant 

watch for all marine mammals and slow 

down, stop their vessel, or alter course 

to avoid striking any marine mammal; 

(3) LOA Holder’s underway vessels 

(e.g., transiting, surveying) operating at 

any speed must have a dedicated visual 

observer on duty at all times to monitor 

for marine mammals within a 180° 

direction of the forward path of the 

vessel (90° port to 90° starboard) located 

at an appropriate vantage point for 

ensuring vessels are maintaining 

appropriate separation distances. Visual 

observers must be equipped with 

alternative monitoring technology (e.g., 

night vision devices, infrared cameras) 

for periods of low visibility (e.g., 

darkness, rain, fog, etc.). The dedicated 

visual observer must receive prior 

training on protected species detection 

and identification, vessel strike 

minimization procedures, how and 

when to communicate with the vessel 

captain, and reporting requirements in 

this subpart. Visual observers may be 

third-party observers (i.e., NMFSapproved PSOs) or trained crew 

members, as defined in paragraph (b)(1) 

of this section; 

(4) LOA Holder must continuously 

monitor the U.S. Coast Guard VHF 

Channel 16 at the onset of transiting 

through the duration of transiting, over 

which North Atlantic right whale 

sightings are broadcasted. At the onset 

of transiting and at least once every 4 

hours, vessel operators and/or trained 

crew member(s) must also monitor the 

project’s Situational Awareness System, 

WhaleAlert, and relevant NOAA 

information systems such as the Right 

Whale Sighting Advisory System 

(RWSAS) for the presence of North 

Atlantic right whales; 

(5) All LOA Holder’s vessels must 

transit at 10 kn or less within any active 

North Atlantic right whale Slow Zone 

(i.e., Dynamic Management Areas 

(DMAs) or acoustically-triggered slow 

zone); 

(6) LOA Holder’s vessels, regardless of 

size, must immediately reduce speed to 

10 kn or less for at least 24 hours when 

a North Atlantic right whale is sighted 

at any distance by any project-related 

personnel or acoustically detected by 

any project-related PAM system. Each 

subsequent observation or acoustic 

detection in the Project area shall trigger 

an additional 24-hour period. If a North 

Atlantic right whale is reported via any 

of the monitoring systems (refer back to 

(b)(4) of this section) within 10 

kilometers (km; 6.2 miles (mi)) of a 

transiting vessel(s), that vessel must 

operate at 10 knots (kn; 11.5 miles per 

hour (mph)) or less for 24 hours 

following the reported detection; 

(7) LOA Holder’s vessels, regardless of 

size, must immediately reduce speed to 

10 kn or less when any large whale 

(other than a North Atlantic right whale) 

is observed within 500 m (1,640 ft) of 

an underway vessel; 

(8) If LOA Holder’s vessel(s) are 

traveling at speeds greater than 10 kn 

(i.e., no speed restrictions are enacted) 

in a transit corridor from a port to the 

Lease Area, in addition to the required 

dedicated visual observer, LOA Holder 

must monitor the transit corridor in 

real-time with PAM prior to and during 

transits. If a North Atlantic right whale 

is detected via visual observation or 

PAM within or approaching the transit 

corridor, all crew transfer vessels must 

travel at 10 kn or less for 24 hours 

following the detection. Each 

subsequent detection shall trigger a 24- 

hour reset. A slowdown in the transit 

corridor expires when there has been no 

further visual or acoustic detection in 

the transit corridor in the past 24 hours; 

(9) LOA Holder’s vessels must 

maintain a minimum separation 

distance of 500 m from North Atlantic 

right whales. If underway, all vessels 

must steer a course away from any 

sighted North Atlantic right whale at 10 

kn or less such that the 500-m minimum 

separation distance requirement is not 

violated. If a North Atlantic right whale 

is sighted within 500 m of an underway 

vessel, that vessel must reduce speed 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
578 Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 

and shift the engine to neutral. Engines 

must not be engaged until the whale has 

moved outside of the vessel’s path and 

beyond 500 m. If a whale is observed 

but cannot be confirmed as a species 

other than a North Atlantic right whale, 

the vessel operator must assume that it 

is a North Atlantic right whale and take 

the vessel strike avoidance measures 

described in this paragraph (b)(9); 

(10) LOA Holder’s vessels must 

maintain a minimum separation 

distance of 100 m (328 ft) from sperm 

whales and non-North Atlantic right 

whale baleen whales. If one of these 

species is sighted within 100 m of a 

transiting vessel, LOA Holder’s vessel 

must reduce speed and shift the engine 

to neutral. Engines must not be engaged 

until the whale has moved outside of 

the vessel’s path and beyond 100 m; 

(11) LOA Holder’s vessels must 

maintain a minimum separation 

distance of 50 m (164 ft) from all 

delphinoid cetaceans and pinnipeds 

with an exception made for those that 

approach the vessel (i.e., bow-riding 

dolphins). If a delphinid cetacean or 

pinniped is sighted within 50 m of a 

transiting vessel, LOA Holder’s vessel 

must shift the engine to neutral, with an 

exception made for those that approach 

the vessel (e.g., bow-riding dolphins). 

Engines must not be engaged until the 

animal(s) has moved outside of the 

vessel’s path and beyond 50 m; 

(12) When a marine mammal(s) is 

sighted while LOA Holder’s vessel(s) is 

transiting, the vessel must take action as 

necessary to avoid violating the relevant 

separation distances (e.g., attempt to 

remain parallel to the animal’s course, 

slow down, and avoid abrupt changes in 

direction until the animal has left the 

area). This measure does not apply to 

any vessel towing gear or any situation 

where respecting the relevant separation 

distance would be unsafe (i.e., any 

situation where the vessel is 

navigationally constrained); 

(13) LOA Holder’s vessels underway 

must not divert or alter course to 

approach any marine mammal; 

(14) LOA Holder is required to abide 

by other speed and approach 

regulations. Nothing in this subpart 

exempts vessels from any other 

applicable marine mammal speed and 

approach regulations; 

(15) LOA Holder must check, daily, 

for information regarding the 

establishment of mandatory or 

voluntary vessel strike avoidance areas 

(i.e., DMAs, SMAs, Slow Zones) and any 

information regarding North Atlantic 

right whale sighting locations; 

(16) LOA Holder must submit a North 

Atlantic Right Whale Vessel Strike 

Avoidance Plan to NMFS Office of 

Protected Resources for review and 

approval at least 180 days prior to the 

planned start of vessel activity. The plan 

must provide details on the vessel-based 

observer and PAM protocols for 

transiting vessels. If a plan is not 

submitted or approved by NMFS prior 

to vessel operations, all project vessels 

transiting, year-round, must travel at 

speeds of 10 kn or less. LOA Holder 

must comply with any approved North 

Atlantic Right Whale Vessel Strike 

Avoidance Plan; and 

(17) Speed over ground will be used 

to measure all vessel speed restrictions. 

(c) WTG, OSS, Met tower foundation 

installation. The following requirements 

apply to impact pile driving activities 

associated with the installation of WTG, 

OSS, and Met tower foundations: 

(1) Impact pile driving must not occur 

December 1 through April 30. 

(2) Monopiles must be no larger than 

11 m in diameter. Hammer energies 

must not exceed 4,400 kilojoules (kJ) for 

monopile installation. No more than one 

monopile may be installed per day, 

unless otherwise approved by NMFS. 

Pin piles for the OSSs must be no larger 

than 3 m in diameter. Hammer energies 

must not exceed 1,500 kJ for 3-m pin 

pile installation. No more than four 3- 

m pin piles may be installed per day. 

Met tower pin piles must be no larger 

than 1.8 m in diameter, and hammer 

energies must not exceed 500 kJ for Met 

tower pin pile installation. No more 

than two 1.8-m pin piles may be 

installed per day. 

(3) LOA Holder must not initiate pile 

driving earlier than 1 hour prior to civil 

sunrise or later than 1.5 hours prior to 

civil sunset, unless the LOA Holder 

submits, and NMFS approves, an 

Alternative Monitoring Plan as part of 

the Pile Driving and Marine Mammal 

Monitoring Plan that reliably 

demonstrates the efficacy of their night 

vision devices. 

(4) Soft-start must occur at the 

beginning of impact driving and at any 

time following a cessation of impact pile 

driving of 30 minutes or longer. Softstart would involve initiating hammer 

operation at a reduced energy level 

(relative to full operating capacity) 

followed by a waiting period. For 

impact pile driving of monopiles and 

pin piles, the LOA Holder must utilize 

a soft-start protocol by performing four 

to six strikes per minute at 10 to 20 

percent of the maximum hammer 

energy, for a minimum of 20 minutes. 

(5) LOA Holder must establish 

clearance and shutdown zones, which 

must be measured using the radial 

distance around the pile being driven. If 

a marine mammal is detected within or 

about to enter the applicable clearance 

zones, prior to the beginning of soft-start 

procedures, impact pile driving must be 

delayed until the animal has been 

visually observed exiting the clearance 

zone or until a specific time period has 

elapsed with no further sightings. The 

specific time periods are 15 minutes for 

small odontocetes and pinnipeds, and 

30 minutes for all other species. 

(6) For North Atlantic right whales, 

any visual observation or acoustic 

detection within the PAM monitoring 

zone must trigger a delay to the 

commencement of pile driving. The 

clearance zone may only be declared 

clear if no North Atlantic right whale 

acoustic or visual detections have 

occurred within the clearance zone 

during the 60-minute monitoring 

period. 

(7) LOA Holder must deploy at least 

two functional noise abatement systems 

that reduce noise levels to the modeled 

harassment isopleths, assuming 10-dB 

attenuation, during all impact pile 

driving and comply with the following 

measures: 

(i) A single bubble curtain must not be 

used; 

(ii) Any bubble curtain(s) must 

distribute air bubbles using an air flow 

rate of at least 0.5 m3/(minute*m). The 

bubble curtain(s) must surround 100 

percent of the piling perimeter 

throughout the full depth of the water 

column. In the unforeseen event of a 

single compressor malfunction, the 

offshore personnel operating the bubble 

curtain(s) must adjust the air supply and 

operating pressure such that the 

maximum possible sound attenuation 

performance of the bubble curtain(s) is 

achieved; 

(iii) The lowest bubble ring must be 

in contact with the seafloor for the full 

circumference of the ring, and the 

weights attached to the bottom ring 

must ensure 100-percent seafloor 

contact; 

(iv) No parts of the ring or other 

objects may prevent full seafloor contact 

with a bubble curtain ring; 

(v) Construction contractors must 

train personnel in the proper balancing 

of airflow to the bubble curtain ring. 

LOA Holder must provide NMFS Office 

of Protected Resources with a bubble 

curtain performance test and 

maintenance report to review within 72 

hours after each pile using a bubble 

curtain is installed. Additionally, a full 

maintenance check (e.g., manually 

clearing holes) must occur prior to each 

pile being installed; and 

(vi) Corrections to the bubble ring(s) 

to meet the performance standards in 

this paragraph (c)(8) must occur prior to 

impact pile driving of monopiles, 3-m 

pin piles, and 1.8-m pin piles. If LOA 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 579 

Holder uses a noise mitigation device in 

addition to the bubble curtain, LOA 

Holder must maintain similar quality 

control measures as described in this 

paragraph (c)(7). 

(8) LOA Holder must utilize NMFSapproved PAM systems, as described in 

paragraph(c)(16) of this section. The 

PAM system components (i.e., acoustic 

buoys) must not be placed closer than 

1 km to the pile being driven so that the 

activities do not mask the PAM system. 

LOA Holder must provide a 

demonstration of and justification for 

the detection range of the system they 

plan to deploy while considering 

potential masking from concurrent pile 

driving and vessel noise. The PAM 

system must be able to detect a 

vocalization of North Atlantic right 

whales up to 10 km (6.2 mi). 

(9) LOA Holder must utilize PSO(s) 

and PAM operator(s), as described in 

§ 217.345(c), to monitor the clearance 

and shutdown zones. At least three onduty PSOs must be on the pile driving 

platform and any additional platforms 

used. 

(10) If a marine mammal is detected 

(visually or acoustically) entering or 

within the respective shutdown zone 

after pile driving has begun, the PSO or 

PAM operator must call for a shutdown 

of pile driving and LOA Holder must 

stop pile driving immediately, unless 

shutdown is not practicable due to 

imminent risk of injury or loss of life to 

an individual or risk of damage to a 

vessel that creates risk of injury or loss 

of life for individuals, or the lead 

engineer determines there is pile refusal 

or pile instability. If pile driving is not 

shut down in one of these situations, 

LOA Holder must reduce hammer 

energy to the lowest level practicable 

and the reason(s) for not shutting down 

must be documented and reported to 

NMFS Office of Protected Resources 

within the applicable monitoring 

reports (e.g., weekly, monthly). 

(11) A visual observation by PSOs at 

any distance or acoustic detection 

within the PAM monitoring zone of a 

North Atlantic right whale triggers 

shutdown requirements as per 

paragraph 10 of this section. If pile 

driving has been shut down due to the 

presence of a North Atlantic right 

whale, pile driving may not restart until 

the North Atlantic right whale has 

neither been visually or acoustically 

detected for 30 minutes. 

(12) If pile driving has been shut 

down due to the presence of a marine 

mammal other than a North Atlantic 

right whale, pile driving must not restart 

until either the marine mammal(s) has 

voluntarily left the specific clearance 

zones and has been visually or 

acoustically confirmed beyond that 

clearance zone, or, when specific time 

periods have elapsed with no further 

sightings or acoustic detections have 

occurred. The specific time periods are 

15 minutes for small odontocetes and 

pinnipeds and 30 minutes for all other 

marine mammal species. In cases where 

these criteria are not met, pile driving 

may restart only if necessary to maintain 

pile stability at which time LOA Holder 

must use the lowest hammer energy 

practicable to maintain stability. 

(13) Pile driving sound levels must 

not exceed modeled distances to NMFS 

marine mammal Level A harassment 

and Level B harassment thresholds 

assuming 10-dB attenuation. 

(14) LOA Holder must conduct sound 

field verification (SFV) measurements 

during pile driving activities associated 

with the installation of, at minimum, 

the first three monopile foundations and 

the first three full jacket foundations 

(inclusive of all pin piles for a specific 

jacket foundation) for each of the three 

construction campaigns. SFV 

measurements must continue until at 

least three consecutive monopiles and 

three entire jacket foundations 

demonstrate noise levels are at or below 

those modeled, assuming 10-decibels 

(dB) of attenuation. Subsequent SFV 

measurements are also required should 

larger piles be installed or if additional 

piles are driven that may produce 

louder sound fields than those 

previously measured (e.g., higher 

hammer energy, greater number of 

strikes, etc.). SFV measurements must 

be conducted as follows: 

(i) Measurements must be made at a 

minimum of four distances from the 

pile(s) being driven, along a single 

transect, in the direction of lowest 

transmission loss (i.e., projected lowest 

transmission loss coefficient), including, 

but not limited to, 750 m (2,460 ft) and 

three additional ranges selected such 

that measurement of Level A 

harassment and Level B harassment 

isopleths are accurate, feasible, and 

avoids extrapolation. At least one 

additional measurement at an azimuth 

90 degrees from the array at 750 m must 

be made. At each location, there must be 

a near bottom and mid-water column 

hydrophone (measurement systems); 

(ii) The recordings must be 

continuous throughout the duration of 

all pile driving of each foundation; 

(iii) The SFV measurement systems 

must have a sensitivity appropriate for 

the expected sound levels from pile 

driving received at the nominal ranges 

throughout the installation of the pile. 

The frequency range of SFV 

measurement systems must cover the 

range of at least 20 hertz (Hz) to 20 

kilohertz (kHz). The SFV measurement 

systems must be designed to have 

omnidirectional sensitivity so that the 

broadband received level of all pile 

driving exceeds the system noise floor 

by at least 10 dB. The dynamic range of 

the SFV measurement system must be 

sufficient such that at each location, the 

signals prevent poor signal-to-noise 

ratios for low amplitude signals and 

avoid clipping, nonlinearity, and 

saturation for high amplitude signals; 

(iv) All hydrophones used in SFV 

measurements systems are required to 

have undergone a full system, traceable 

laboratory calibration conforming to 

International Electrotechnical 

Commission (IEC) 60565, or an 

equivalent standard procedure, from a 

factory or accredited source to ensure 

the hydrophone receives accurate sound 

levels, at a date not to exceed 2 years 

before deployment. Additional in-situ 

calibration checks using a pistonphone 

are required to be performed before and 

after each hydrophone deployment. If 

the measurement system employs filters 

via hardware or software (e.g., highpass, low-pass, etc.), which is not 

already accounted for by the calibration, 

the filter performance (i.e., the filter’s 

frequency response) must be known, 

reported, and the data corrected before 

analysis; 

(v) LOA Holder must be prepared 

with additional equipment 

(hydrophones, recording devices, 

hydrophone calibrators, cables, 

batteries, etc.), which exceeds the 

amount of equipment necessary to 

perform the measurements, such that 

technical issues can be mitigated before 

measurement; 

(vi) LOA Holder must submit interim 

SFV reports within 48 hours after each 

foundation is measured (see § 217.345(g) 

for interim and final reporting 

requirements); 

(vii) If any of the interim SFV 

measurement reports submitted for the 

first three monopiles exceed the 

modeled distances to NMFS marine 

mammal Level A harassment and Level 

B harassment thresholds assuming 10- 

dB attenuation, then LOA Holder must 

implement additional sound attenuation 

measures on all subsequent foundations. 

LOA Holder must also increase 

clearance and shutdown zone sizes to 

those identified by NMFS until SFV 

measurements on at least three 

additional foundations demonstrate 

acoustic distances to harassment 

thresholds meet or are less than those 

modeled assuming 10 dB of attenuation. 

LOA Holder must optimize the sound 

attenuation systems (e.g., ensure hose 

maintenance, pressure testing, etc.) to 

meet noise levels modeled, assuming 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
580 Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 

10-dB attenuation, within three piles or 

else foundation installation activities 

must cease until NMFS and LOA Holder 

can evaluate the situation and ensure 

future piles do not exceed noise levels 

modeled assuming 10-dB attenuation; 

(viii) If, after additional measurements 

conducted pursuant to requirements of 

paragraph (14)(vii) of this section, 

acoustic measurements indicate that 

ranges to isopleths corresponding to the 

Level A harassment and Level B 

harassment thresholds are less than the 

ranges predicted by modeling (assuming 

10-dB attenuation), LOA Holder may 

request a modification of the clearance 

and shutdown zones from the NMFS 

Office of Protected Resources. For 

NMFS Office of Protected Resources to 

consider a modification request for 

reduced zone sizes, LOA Holder must 

have conducted SFV measurements on 

an additional three foundations (for 

either/or monopile and jackets) and 

ensure that subsequent foundations 

would be installed under conditions 

that are predicted to produce smaller 

harassment zones than those modeled 

assuming 10 dB of attenuation; 

(ix) LOA Holder must conduct SFV 

measurements as described in c(14) 

upon commencement of turbine 

operations to estimate turbine 

operational source levels, in accordance 

with a NMFS-approved Foundation 

Installation Pile Driving SFV Plan. SFV 

must be conducted in the same manner 

as previously described in 

§ 217.304(c)(14), with appropriate 

adjustments to measurement distances, 

number of hydrophones, and 

hydrophone sensitivities being made, as 

necessary; and 

(x) LOA Holder must submit a SFV 

Plan to NMFS Office of Protected 

Resources for review and approval at 

least 180 days prior to planned start of 

foundation installation activities and 

abide by the Plan if approved. At 

minimum, the SFV Plan must describe 

how LOA Holder would ensure that the 

first three monopile foundation/entire 

jacket foundation (inclusive of all pin 

piles for a jacket foundation) installation 

sites selected for SFV measurements are 

representative of the rest of the 

monopile and/or jacket foundation 

installation sites such that future pile 

installation events are anticipated to 

produce similar sound levels to those 

piles measured. In the case that these 

sites/scenarios are not determined to be 

representative of all other pile 

installation sites, LOA Holder must 

include information in the SFV Plan on 

how additional sites/scenarios would be 

selected for SFV measurements. The 

SFV Plan must also include 

methodology for collecting, analyzing, 

and preparing SFV measurement data 

for submission to NMFS Office of 

Protected Resources and describe how 

the effectiveness of the sound 

attenuation methodology would be 

evaluated based on the results. SFV for 

pile driving may not occur until NMFS 

approves the SFV Plan for this activity. 

(15) LOA Holder must submit a 

Foundation Installation Pile Driving 

Marine Mammal Monitoring Plan to 

NMFS Office of Protected Resources for 

review and approval at least 180 days 

prior to planned start of pile driving and 

abide by the Plan if approved. LOA 

Holder must obtain both NMFS Office of 

Protected Resources and NMFS Greater 

Atlantic Regional Fisheries Office 

Protected Resources Division’s 

concurrence with this Plan prior to the 

start of any pile driving. The Plan must 

include a description of all monitoring 

equipment and PAM and PSO protocols 

(including number and location of 

PSOs) for all pile driving. No foundation 

pile installation can occur without 

NMFS’ approval of the Plan. 

(16) LOA Holder must submit a 

Passive Acoustic Monitoring Plan (PAM 

Plan) to NMFS Office of Protected 

Resources for review and approval at 

least 180 days prior to the planned start 

of foundation installation activities 

(impact pile driving) and abide by the 

Plan if approved. The PAM Plan must 

include a description of all proposed 

PAM equipment, address how the 

proposed passive acoustic monitoring 

must follow standardized measurement, 

processing methods, reporting metrics, 

and metadata standards for offshore 

wind as described in ‘‘NOAA and 

BOEM Minimum Recommendations for 

Use of Passive Acoustic Listening 

Systems in Offshore Wind Energy 

Development Monitoring and Mitigation 

Programs’’ (2021). The Plan must 

describe all proposed PAM equipment, 

procedures, and protocols including 

proof that vocalizing North Atlantic 

right whales will be detected within the 

clearance and shutdown zones. No pile 

installation can occur if LOA Holder’s 

PAM Plan does not receive approval 

from NMFS Office of Protected 

Resources and NMFS Greater Atlantic 

Regional Fisheries Office Protected 

Resources Division. 

(d) HRG surveys. The following 

requirements apply to HRG surveys 

operating sub-bottom profilers (SBPs) 

(i.e., boomers, sparkers, and 

Compressed High Intensity Radiated 

Pulse (CHIRPS)): 

(1) LOA Holder must establish and 

implement clearance and shutdown 

zones for HRG surveys using visual 

monitoring, as described in paragraph 

(d) of this section; 

(2) LOA Holder must utilize PSO(s), 

as described in § 217.345(f); 

(3) SBPs (hereinafter referred to as 

‘‘acoustic sources’’) must be deactivated 

when not acquiring data or preparing to 

acquire data, except as necessary for 

testing. Acoustic sources must be used 

at the lowest practicable source level to 

meet the survey objective, when in use, 

and must be turned off when they are 

not necessary for the survey; 

(4) LOA Holder is required to rampup acoustic sources prior to 

commencing full power, unless the 

equipment operates on a binary on/off 

switch, and ensure visual clearance 

zones are observable (e.g., not obscured 

from observation by darkness, rain, fog, 

etc.) and clear of marine mammals, as 

determined by the Lead PSO, for at least 

30 minutes immediately prior to the 

initiation of survey activities using 

acoustic sources specified in the LOA. 

Ramp-up and activation must be 

delayed if a marine mammal(s) enters its 

respective shutdown zone. Ramp-up 

and activation may only be reinitiated if 

the animal(s) has been observed exiting 

its respective shutdown zone or until 15 

minutes for small odontocetes and 

pinnipeds, and 30 minutes for all other 

species, has elapsed with no further 

sightings; 

(5) Prior to a ramp-up procedure 

starting or activating acoustic sources, 

the acoustic source operator (operator) 

must notify a designated PSO of the 

planned start of ramp-up as agreed upon 

with the Lead PSO. The notification 

time should not be less than 60 minutes 

prior to the planned ramp-up or 

activation in order to allow the PSOs 

time to monitor the clearance zone(s) for 

30 minutes prior to the initiation of 

ramp-up or activation (pre-start 

clearance). During this 30-minute prestart clearance period, the entire 

applicable clearance zones must be 

visible, except as indicated in paragraph 

(d)(11) of this section; 

(6) Ramp-ups must be scheduled so as 

to minimize the time spent with the 

source activated; 

(7) A PSO conducting pre-start 

clearance observations must be notified 

again immediately prior to reinitiating 

ramp-up procedures and the operator 

must receive confirmation from the PSO 

to proceed; 

(8) LOA Holder must implement a 30- 

minute clearance period of the clearance 

zones immediately prior to the 

commencing of the survey or when 

there is more than a 30-minute break in 

survey activities or PSO monitoring. A 

clearance period is a period when no 

marine mammals are detected in the 

relevant zone; 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 581 

(9) If a marine mammal is observed 

within a clearance zone during the 

clearance period, ramp-up or acoustic 

surveys may not begin until the 

animal(s) has been observed voluntarily 

exiting its respective clearance zone or 

until a specific time period has elapsed 

with no further sighting. The specific 

time period is 15 minutes for small 

odontocetes and pinnipeds, and 30 

minutes for all other species; 

(10) In any case when the clearance 

process has begun in conditions with 

good visibility, including via the use of 

night vision equipment (infrared (IR)/ 

thermal camera), and the Lead PSO has 

determined that the clearance zones are 

clear of marine mammals, survey 

operations would be allowed to 

commence (i.e., no delay is required) 

despite periods of inclement weather 

and/or loss of daylight. Ramp-up may 

occur at times of poor visibility, 

including nighttime, if appropriate 

visual monitoring has occurred with no 

detections of marine mammals in the 30 

minutes prior to beginning ramp-up; 

(11) Once the survey has commenced, 

LOA Holder must shut down acoustic 

sources if a marine mammal enters a 

respective shutdown zone, except in 

cases when the shutdown zones become 

obscured for brief periods due to 

inclement weather, survey operations 

would be allowed to continue (i.e., no 

shutdown is required) so long as no 

marine mammals have been detected. 

The shutdown requirement does not 

apply to small delphinids of the 

following genera: Delphinus, Stenella, 

Lagenorhynchus, and Tursiops. If there 

is uncertainty regarding the 

identification of a marine mammal 

species (i.e., whether the observed 

marine mammal belongs to one of the 

delphinid genera for which shutdown is 

waived), the PSOs must use their best 

professional judgment in making the 

decision to call for a shutdown. 

Shutdown is required if a delphinid that 

belongs to a genus other than those 

specified in this paragraph (d)(11) is 

detected in the shutdown zone; 

(12) If an acoustic source has been 

shut down due to the presence of a 

marine mammal, the use of an acoustic 

source may not commence or resume 

until the animal(s) has been confirmed 

to have left the Level B harassment zone 

or until a full 15 minutes (for small 

odontocetes and seals) or 30 minutes 

(for all other marine mammals) have 

elapsed with no further sighting; 

(13) LOA Holder must immediately 

shut down any acoustic source if a 

marine mammal is sighted entering or 

within its respective shutdown zones. If 

there is uncertainty regarding the 

identification of a marine mammal 

species (i.e., whether the observed 

marine mammal belongs to one of the 

delphinid genera for which shutdown is 

waived), the PSOs must use their best 

professional judgment in making the 

decision to call for a shutdown. 

Shutdown is required if a delphinid that 

belongs to a genus other than those 

specified in paragraph (d)(11) of this 

section is detected in the shutdown 

zone; and 

(14) If an acoustic source is shut down 

for a period longer than 30 minutes, all 

clearance and ramp-up procedures must 

be initiated. If an acoustic source is shut 

down for reasons other than mitigation 

(e.g., mechanical difficulty) for less than 

30 minutes, acoustic sources may be 

activated again without ramp-up only if 

PSOs have maintained constant 

observation and no additional 

detections of any marine mammal 

occurred within the respective 

shutdown zones. 

(e) Fisheries monitoring surveys. The 

following measures apply to fishery 

monitoring surveys: 

(1) Survey gear must be deployed as 

soon as possible once the vessel arrives 

on station. Gear must not be deployed 

if there is a risk of interaction with 

marine mammals. Gear may be 

deployed after 15 minutes of no marine 

mammal sightings within 1 nautical 

mile (nmi; 1,852 m) of the sampling 

station; 

(2) LOA Holder and its cooperating 

institutions, contracted vessels, or 

commercially hired captains must 

implement the following ‘‘move-on’’ 

rule: If marine mammals are sighted 

within 1 nmi of the planned location 

and 15 minutes before gear deployment, 

then LOA Holder and its cooperating 

institutions, contracted vessels, or 

commercially hired captains, as 

appropriate, must move the vessel away 

from the marine mammal to a different 

section of the sampling area. If, after 

moving on, marine mammals are still 

visible from the vessel, LOA Holder and 

its cooperating institutions, contracted 

vessels, or commercially hired captains 

must move again or skip the station; 

(3) If a marine mammal is at risk of 

interacting with or becoming entangled 

in the gear after the gear is deployed or 

set, all gear must be immediately 

removed from the water. If marine 

mammals are sighted before the gear is 

fully removed from the water, the vessel 

must slow its speed and maneuver the 

vessel away from the animals to 

minimize potential interactions with the 

observed animal; 

(4) LOA Holder must maintain visual 

marine mammal monitoring effort 

during the entire period of time that 

gear is in the water (i.e., throughout gear 

deployment, fishing, and retrieval); 

(5) All fisheries monitoring gear must 

be fully cleaned and repaired (if 

damaged) before each use/deployment; 

(6) LOA Holder’s fixed gear must 

comply with the Atlantic Large Whale 

Take Reduction Plan regulations at 50 

CFR 229.32 during fisheries monitoring 

surveys; 

(7) All gear must be emptied as close 

to the deck/sorting area and as quickly 

as possible after retrieval; 

(8) During any survey that uses 

vertical lines, buoy lines must be 

weighted and must not float at the 

surface of the water and all groundlines 

must consist of sinking lines. All 

groundlines must be composed entirely 

of sinking lines. Buoy lines must utilize 

weak links. Weak links must break 

cleanly leaving behind the bitter end of 

the line. The bitter end of the line must 

be free of any knots when the weak link 

breaks. Splices are not considered to be 

knots. The attachment of buoys, toggles, 

or other floatation devices to 

groundlines is prohibited; 

(9) All in-water survey gear, including 

buoys, must be properly labeled with 

the scientific permit number or 

identification as LOA Holder’s research 

gear. All labels and markings on the 

gear, buoys, and buoy lines must also be 

compliant with the Atlantic Large 

Whale Take Reduction Plan regulations 

at 50 CFR 229.32, and all buoy markings 

must comply with instructions received 

by the NOAA Greater Atlantic Regional 

Fisheries Office Protected Resources 

Division; 

(10) All survey gear must be removed 

from the water whenever not in active 

survey use (i.e., no wet storage); and 

(11) All reasonable efforts, that do not 

compromise human safety, must be 

undertaken to recover gear. 

§ 217.345 Monitoring and reporting 

requirements. 

(a) Protected species observer (PSO) 

and passive acoustic monitoring (PAM) 

operator qualifications. LOA Holder 

must implement the following measures 

applicable to PSOs and PAM operators: 

(1) LOA Holder must use 

independent, NMFS-approved PSOs 

and PAM operators, meaning that the 

PSOs and PAM operators must be 

employed by a third-party observer 

provider, must have no tasks other than 

to conduct observational effort, collect 

data, and communicate with and 

instruct relevant crew with regard to the 

presence of protected species and 

mitigation requirements; 

(2) All PSOs and PAM operators must 

have successfully attained a bachelor’s 

degree from an accredited college or 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
582 Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 

university with a major in one of the 

natural sciences, a minimum of 30 

semester hours or equivalent in the 

biological sciences, and at least one 

undergraduate course in math or 

statistics. The educational requirements 

may be waived if the PSO or PAM 

operator has acquired the relevant skills 

through a suitable amount of alternate 

experience. Requests for such a waiver 

must be submitted to NMFS Office of 

Protected Resources and must include 

written justification containing 

alternative experience. Alternate 

experience that may be considered 

includes, but is not limited to previous 

work experience conducting academic, 

commercial, or government-sponsored 

marine mammal visual and/or acoustic 

surveys, or previous work experience as 

a PSO/PAM operator; 

(3) PSOs must have visual acuity in 

both eyes (with correction of vision 

being permissible) sufficient enough to 

discern moving targets on the water’s 

surface with the ability to estimate the 

target size and distance (binocular use is 

allowable); ability to conduct field 

observations and collect data according 

to the assigned protocols; sufficient 

training, orientation, or experience with 

the construction operation to provide 

for personal safety during observations; 

writing skills sufficient to document 

observations, including but not limited 

to, the number and species of marine 

mammals observed, the dates and times 

when in-water construction activities 

were conducted, the dates and time 

when in-water construction activities 

were suspended to avoid potential 

incidental take of marine mammals from 

construction noise within a defined 

shutdown zone, and marine mammal 

behavior; and the ability to 

communicate orally, by radio, or inperson, with project personnel to 

provide real-time information on marine 

mammals observed in the area; 

(4) All PSOs must be trained in 

northwestern Atlantic Ocean marine 

mammal identification and behaviors 

and must be able to conduct field 

observations and collect data according 

to assigned protocols. Additionally, 

PSOs must have the ability to work with 

all required and relevant software and 

equipment necessary during 

observations (as described in paragraphs 

(b)(6) and (7) of this section; 

(5) All PSOs and PAM operators must 

successfully complete a relevant 

training course within the last 5 years, 

including obtaining a certificate of 

course completion; 

(6) PSOs and PAM operators are 

responsible for obtaining NMFS’ 

approval. NMFS may approve PSOs and 

PAM operators as conditional or 

unconditional. A conditionally 

approved PSO or PAM operator may be 

one who has completed training in the 

last 5 years but has not yet attained the 

requisite field experience. An 

unconditionally approved PSO or PAM 

operator is one who has completed 

training within the last 5 years and 

attained the necessary experience (i.e., 

demonstrate experience with 

monitoring for marine mammals at 

clearance and shutdown zone sizes 

similar to those produced during the 

respective activity). Lead PSO or PAM 

operators must be unconditionally 

approved and have a minimum of 90 

days in a northwestern Atlantic Ocean 

offshore environment performing the 

role (either visual or acoustic), with the 

conclusion of the most recent relevant 

experience not more than 18 months 

previous. A conditionally approved PSO 

or PAM operator must be paired with an 

unconditionally approved PSO or PAM 

operator; 

(7) PSOs for HRG surveys may be 

unconditionally or conditionally 

approved. PSOs and PAM operators for 

foundation installation activities must 

be unconditionally approved; 

(8) At least one on-duty PSO and 

PAM operator, where applicable, for 

each activity (e.g., impact pile driving, 

vibratory pile driving, and HRG surveys) 

must be designated as the Lead PSO or 

Lead PAM operator; 

(9) LOA Holder must submit NMFS 

previously approved PSOs and PAM 

operators to NMFS Office of Protected 

Resources for review and confirmation 

of their approval for specific roles at 

least 30 days prior to commencement of 

the activities requiring PSOs/PAM 

operators or 15 days prior to when new 

PSOs/PAM operators are required after 

activities have commenced; 

(10) For prospective PSOs and PAM 

operators not previously approved, or 

for PSOs and PAM operators whose 

approval is not current, LOA Holder 

must submit resumes for approval at 

least 60 days prior to PSO and PAM 

operator use. Resumes must include 

information related to relevant 

education, experience, and training, 

including dates, duration, location, and 

description of prior PSO or PAM 

operator experience. Resumes must be 

accompanied by relevant 

documentation of successful completion 

of necessary training; 

(11) PAM operators are responsible 

for obtaining NMFS approval. To be 

approved as a PAM operator, the person 

must meet the following qualifications: 

The PAM operator must demonstrate 

that they have prior experience with 

real-time acoustic detection systems 

and/or have completed specialized 

training for operating PAM systems and 

detecting and identifying Atlantic 

Ocean marine mammals sounds, in 

particular: North Atlantic right whale 

sounds, humpback whale sounds, and 

how to deconflict them from similar 

North Atlantic right whale sounds, and 

other co-occurring species’ sounds in 

the area including sperm whales; must 

be able to distinguish between whether 

a marine mammal or other species 

sound is detected, possibly detected, or 

not detected, and similar terminology 

must be used across companies/projects; 

Where localization of sounds or 

deriving bearings and distance are 

possible, the PAM operators need to 

have demonstrated experience in using 

this technique; PAM operators must be 

independent observers (i.e., not 

construction personnel); PAM operators 

must demonstrate experience with 

relevant acoustic software and 

equipment; PAM operators must have 

the qualifications and relevant 

experience/training to safely deploy and 

retrieve equipment and program the 

software, as necessary; PAM operators 

must be able to test software and 

hardware functionality prior to 

operation; and PAM operators must 

have evaluated their acoustic detection 

software using the PAM Atlantic baleen 

whale annotated data set available at 

National Centers for Environmental 

Information (NCEI) and provide 

evaluation/performance metric; 

(12) PAM operators must be able to 

review and classify acoustic detections 

in real-time (prioritizing North Atlantic 

right whales and noting detection of 

other cetaceans) during the real-time 

monitoring periods; 

(13) PSOs may work as PAM 

operators and vice versa, pending 

NMFS-approval; however, they may 

only perform one role at any time and 

must not exceed work time restrictions, 

which must be tallied cumulatively; and 

(14) All PSOs and PAM operators 

must complete a Permits and 

Environmental Compliance Plan 

training and a 2-day refresher session 

that must be held with the PSO provider 

and Project compliance representative(s) 

prior to the start of in-water project 

activities (e.g., HRG survey, foundation 

installation, etc.). 

(b) General PSO and PAM operator 

requirements. The following measures 

apply to PSOs and PAM operators and 

must be implemented by LOA Holder: 

(1) PSOs must monitor for marine 

mammals prior to, during, and 

following impact pile driving and HRG 

surveys that use sub-bottom profilers 

(with specific monitoring durations and 

needs described in paragraphs (c) 

through (f) of this section, respectively). 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 583 

Monitoring must be done while free 

from distractions and in a consistent, 

systematic, and diligent manner; 

(2) For foundation installation, PSOs 

must visually clear (i.e., confirm no 

observations of marine mammals) the 

entire minimum visibility zone for a full 

30 minutes immediately prior to 

commencing activities. For HRG 

surveys, which do not have a minimum 

visibility zone, the entire clearance zone 

must be visually cleared and as much of 

the Level B harassment zone as possible; 

(3) All PSOs must be located at the 

best vantage point(s) on any platform, as 

determined by the Lead PSO, in order 

to obtain 360-degree visual coverage of 

the entire clearance and shutdown 

zones around the activity area, and as 

much of the Level B harassment zone as 

possible. PAM operators may be located 

on a vessel or remotely on-shore, the 

PAM operator(s) must assist PSOs in 

ensuring full coverage of the clearance 

and shutdown zones. The PAM operator 

must monitor to and past the clearance 

zone for large whales; 

(4) All on-duty PSOs must remain in 

real-time contact with the on-duty PAM 

operator(s), PAM operators must 

immediately communicate all acoustic 

detections of marine mammals to PSOs, 

including any determination regarding 

species identification, distance, and 

bearing (where relevant) relative to the 

pile being driven and the degree of 

confidence (e.g., possible, probable 

detection) in the determination. All onduty PSOs and PAM operator(s) must 

remain in contact with the on-duty 

construction personnel responsible for 

implementing mitigations (e.g., delay to 

pile driving) to ensure communication 

on marine mammal observations can 

easily, quickly, and consistently occur 

between all on-duty PSOs, PAM 

operator(s), and on-water Project 

personnel; 

(5) The PAM operator must inform the 

Lead PSO(s) on duty of animal 

detections approaching or within 

applicable ranges of interest to the 

activity occurring via the data collection 

software system (i.e., Mysticetus or 

similar system) who must be 

responsible for requesting that the 

designated crewmember implement the 

necessary mitigation procedures (i.e., 

delay); 

(6) PSOs must use high magnification 

(25x) binoculars, standard handheld 

(7x) binoculars, and the naked eye to 

search continuously for marine 

mammals. During foundation 

installation, at least two PSOs on the 

pile driving vessel must be equipped 

with functional Big Eye binoculars (e.g., 

25 * 150; 2.7 view angle; individual 

ocular focus; height control); these must 

be pedestal mounted on the deck at the 

best vantage point that provides for 

optimal sea surface observation and 

PSO safety. PAM operators must have 

the appropriate equipment (i.e., a 

computer station equipped with a data 

collection software system available 

wherever they are stationed) and use a 

NMFS-approved PAM system to 

conduct monitoring. PAM systems are 

approved through the PAM Plan as 

described in § 217.344(c)(17); and 

(7) PSOs and PAM operators must not 

exceed 4 consecutive watch hours on 

duty at any time, must have a 2-hour 

(minimum) break between watches, and 

must not exceed a combined watch 

schedule of more than 12 hours in a 24- 

hour period. If the schedule includes 

PSOs and PAM operators on-duty for 2- 

hour shifts, a minimum 1-hour break 

between watches must be allowed. 

(c) PSO and PAM operator 

requirements during WTG, OSS, and 

Met Tower foundation installation. The 

following measures apply to PSOs and 

PAM operators during WTG, OSS, and 

Met tower foundation installation and 

must be implemented by LOA Holder: 

(1) PSOs and PAM operator(s), using 

a NMFS-approved PAM system, must 

monitor for marine mammals 60 

minutes prior to, during, and 30 

minutes following all pile driving 

activities. If PSOs cannot visually 

monitor the minimum visibility zone 

prior to impact pile driving at all times 

using the equipment described in 

paragraphs (b)(6) and (7) of this section, 

pile driving operations must not 

commence or must shutdown if they are 

currently active; 

(2) At least three on-duty PSOs must 

be stationed and observing from the 

activity platform during impact pile 

driving and at least three on-duty PSOs 

must be stationed on each dedicated 

PSO vessel. Concurrently, at least one 

PAM operator per acoustic data stream 

(equivalent to the number of acoustic 

buoys) must be actively monitoring for 

marine mammals 60 minutes before, 

during, and 30 minutes after impact pile 

driving in accordance with a NMFSapproved PAM Plan; and 

(3) LOA Holder must conduct PAM 

for at least 24 hours immediately prior 

to pile driving activities. The PAM 

operator must review all detections from 

the previous 24-hour period 

immediately prior to pile driving 

activities. 

(d) PSO requirements during HRG 

surveys. The following measures apply 

to PSOs during HRG surveys using 

acoustic sources that have the potential 

to result in harassment and must be 

implemented by LOA Holder: 

(1) At least one PSO must be on active 

duty monitoring during HRG surveys 

conducted during daylight (i.e., from 30 

minutes prior to civil sunrise through 30 

minutes following civil sunset) and two 

PSOs during nighttime surveying (if it 

occurs); 

(2) PSOs on HRG vessels must begin 

monitoring 30 minutes prior to 

activating acoustic sources, during the 

use of these acoustic sources, and for 30 

minutes after use of these acoustic 

sources has ceased; 

(3) Any observations of marine 

mammals must be communicated to 

PSOs on all nearby survey vessels 

during concurrent HRG surveys; and 

(4) During daylight hours when 

survey equipment is not operating, LOA 

Holder must ensure that visual PSOs 

conduct, as rotation schedules allow, 

observations for comparison of sighting 

rates and behavior with and without use 

of the specified acoustic sources. 

(e) Monitoring requirements during 

fisheries monitoring surveys. The 

following measures apply during 

fisheries monitoring surveys and must 

be implemented by LOA Holder: 

(1) All captains and crew conducting 

fishery surveys must be trained in 

marine mammal detection and 

identification; and 

(2) Marine mammal monitoring must 

be conducted within 1 nmi from the 

planned survey location by the trained 

captain and/or a member of the 

scientific crew for 15 minutes prior to 

deploying gear, throughout gear 

deployment and use, and for 15 minutes 

after haul back. 

(f) Reporting. LOA Holder must 

comply with the following reporting 

measures: 

(1) Prior to initiation of any on-water 

project activities, LOA Holder must 

demonstrate in a report submitted to 

NMFS Office of Protected Resources 

that all required training for LOA 

Holder personnel (including the vessel 

crews, vessel captains, PSOs, and PAM 

operators) has been completed. 

(2) LOA Holder must use a 

standardized reporting system during 

the effective period of the LOA. All data 

collected related to the Project must be 

recorded using industry-standard 

software that is installed on field 

laptops and/or tablets. Unless stated 

otherwise, all reports must be submitted 

to NMFS Office of Protected Resources 

(PR.ITP.MonitoringReports@noaa.gov), 

dates must be in MM/DD/YYYY format, 

and location information must be 

provided in Decimal Degrees and with 

the coordinate system information (e.g., 

NAD83, WGS84, etc.). 

(3) For all visual monitoring efforts 

and marine mammal sightings, the 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
584 Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 

following information must be collected 

and reported to NMFS Office of 

Protected Resources: the date and time 

that monitored activity begins or ends; 

the construction activities occurring 

during each observation period; the 

watch status (i.e., sighting made by PSO 

on/off effort, opportunistic, crew, 

alternate vessel/platform); the PSO who 

sighted the animal; the time of sighting; 

the weather parameters (e.g., wind 

speed, percent cloud cover, visibility); 

the water conditions (e.g., Beaufort sea 

state, tide state, water depth); all marine 

mammal sightings, regardless of 

distance from the construction activity; 

species (or lowest possible taxonomic 

level possible); the pace of the 

animal(s); the estimated number of 

animals (minimum/maximum/high/ 

low/best); the estimated number of 

animals by cohort (e.g., adults, 

yearlings, juveniles, calves, group 

composition, etc.); the description (i.e., 

as many distinguishing features as 

possible of each individual seen, 

including length, shape, color, pattern, 

scars or markings, shape and size of 

dorsal fin, shape of head, and blow 

characteristics); the description of any 

marine mammal behavioral observations 

(e.g., observed behaviors such as feeding 

or traveling) and observed changes in 

behavior, including an assessment of 

behavioral responses thought to have 

resulted from the specific activity; the 

animal’s closest distance and bearing 

from the pile being driven or specified 

HRG equipment and estimated time 

entered or spent within the Level A 

harassment and/or Level B harassment 

zone(s); the activity at time of sighting 

(e.g., impact pile driving, construction 

survey), use of any noise attenuation 

device(s), and specific phase of activity 

(e.g., ramp-up of HRG equipment, HRG 

acoustic source on/off, soft-start for pile 

driving, active pile driving, etc.); the 

marine mammal occurrence in Level A 

harassment or Level B harassment 

zones; the description of any mitigationrelated action implemented, or 

mitigation-related actions called for but 

not implemented, in response to the 

sighting (e.g., delay, shutdown, etc.) and 

time and location of the action; other 

human activity in the area, and; other 

applicable information, as required in 

any LOAs issued under § 217.346. 

(4) LOA Holder must compile and 

submit weekly reports during 

foundation installation to NMFS Office 

of Protected Resources that document 

the daily start and stop of all pile 

driving associated with the Project; the 

start and stop of associated observation 

periods by PSOs; details on the 

deployment of PSOs; a record of all 

detections of marine mammals (acoustic 

and visual); any mitigation actions (or if 

mitigation actions could not be taken, 

provide reasons why); and details on the 

noise attenuation system(s) used and its 

performance. Weekly reports are due on 

Wednesday for the previous week 

(Sunday to Saturday) and must include 

the information required under this 

section. The weekly report must also 

identify which turbines become 

operational and when (a map must be 

provided). Once all foundation pile 

installation is completed, weekly 

reports are no longer required by LOA 

Holder. 

(5) LOA Holder must compile and 

submit monthly reports to NMFS Office 

of Protected Resources during 

foundation installation that include a 

summary of all information in the 

weekly reports, including project 

activities carried out in the previous 

month, vessel transits (number, type of 

vessel, MMIS number, and route), 

number of piles installed, all detections 

of marine mammals, and any mitigative 

action taken. Monthly reports are due 

on the 15th of the month for the 

previous month. The monthly report 

must also identify which turbines 

become operational and when (a map 

must be provided). Full PAM detection 

data and metadata must also be 

submitted monthly on the 15th of every 

month for the previous month via the 

webform on the NMFS North Atlantic 

Right Whale Passive Acoustic Reporting 

System website at https://

www.fisheries.noaa.gov/resource/ 

document/passive-acoustic-reportingsystem-templates. 

(6) LOA Holder must submit a draft 

annual report to NMFS Office of 

Protected Resources no later than 90 

days following the end of a given 

calendar year. LOA Holder must 

provide a final report within 30 days 

following resolution of NMFS’ 

comments on the draft report. The draft 

and final reports must detail the 

following: the total number of marine 

mammals of each species/stock detected 

and how many were within the 

designated Level A harassment and 

Level B harassment zone(s) with 

comparison to authorized take of marine 

mammals for the associated activity 

type; marine mammal detections and 

behavioral observations before, during, 

and after each activity; what mitigation 

measures were implemented (i.e., 

number of shutdowns or clearance zone 

delays, etc.) or, if no mitigative actions 

was taken, why not; operational details 

(i.e., days and duration of impact and 

vibratory pile driving, days, and amount 

of HRG survey effort, etc.); any PAM 

systems used; the results, effectiveness, 

and which noise attenuation systems 

were used during relevant activities 

(i.e., impact pile driving); summarized 

information related to situational 

reporting; and any other important 

information relevant to the Project, 

including additional information that 

may be identified through the adaptive 

management process. 

(7) LOA Holder must submit its draft 

5-year report to NMFS Office of 

Protected Resources on all visual and 

acoustic monitoring conducted within 

90 calendar days of the completion of 

activities occurring under the LOA. At 

a minimum, the draft and final 5-year 

report must include: the total number 

(annually and across all 5 years) of 

marine mammals of each species/stock 

detected and how many were detected 

within the designated Level A 

harassment and Level B harassment 

zone(s) with comparison to authorized 

take of marine mammals for the 

associated activity type; a summary 

table(s) indicating the amount of each 

activity type (e.g., pile installation, 

HRG) completed in each of the 5 years 

and total; GIS shapefile(s) of the final 

location of all piles, cable routes, and 

other permanent structures including an 

indication of what year installed and 

began operating; GIS shapefile of all 

North Atlantic right whale sightings, 

including dates and group sizes; a 5- 

year summary and evaluation of all SFV 

data collected; a 5-year summary and 

evaluation of all PAM data collected; a 

5-year summary and evaluation of 

marine mammal behavioral 

observations; a 5-year summary and 

evaluation of mitigation and monitoring 

implementation and effectiveness; a list 

of recommendations to inform 

environmental compliance assessments 

for future offshore wind actions. A 5- 

year report must be prepared and 

submitted within 60 calendar days 

following receipt of any NMFS Office of 

Protected Resources comments on the 

draft report. If no comments are 

received from NMFS Office of Protected 

Resources within 60 calendar days of 

NMFS Office of Protected Resources 

receipt of the draft report, the report 

shall be considered final. 

(8) For those foundation piles 

requiring SFV measurements, LOA 

Holder must provide the initial results 

of the SFV measurements to NMFS 

Office of Protected Resources in an 

interim report after each foundation 

installation event as soon as they are 

available and prior to a subsequent 

foundation installation, but no later 

than 48 hours after each completed 

foundation installation event. The 

report must include, at minimum: 

hammer energies/schedule used during 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 585 

pile driving, including, the total number 

of strikes and the maximum hammer 

energy; the model-estimated acoustic 

ranges (R95%) to compare with the realworld sound field measurements; peak 

sound pressure level (SPLpk), root-meansquare sound pressure level that 

contains 90 percent of the acoustic 

energy (SPLrms), and sound exposure 

level (SEL, in single strike for pile 

driving, SELss,), for each hydrophone, 

including at least the maximum, 

arithmetic mean, minimum, median 

(L50) and L5 (95 percent exceedance) 

statistics for each metric; estimated 

marine mammal Level A harassment 

and Level B harassment isopleths, 

calculated using the maximum-overdepth L5 (95 percent exceedance level, 

maximum of both hydrophones) of the 

associated sound metric; comparison of 

modeled results assuming 10-dB 

attenuation against the measured marine 

mammal Level A harassment and Level 

B harassment acoustic isopleths; 

estimated transmission loss coefficients; 

pile identifier name, location of the pile 

and each hydrophone array in latitude/ 

longitude; depths of each hydrophone; 

one-third-octave band single strike SEL 

spectra; if filtering is applied, full filter 

characteristics must be reported; and 

hydrophone specifications including the 

type, model, and sensitivity. LOA 

Holder must also report any immediate 

observations which are suspected to 

have a significant impact on the results 

including but not limited to: observed 

noise mitigation system issues, 

obstructions along the measurement 

transect, and technical issues with 

hydrophones or recording devices. If 

any in-situ calibration checks for 

hydrophones reveal a calibration drift 

greater than 0.75 dB, pistonphone 

calibration checks are inconclusive, or 

calibration checks are otherwise not 

effectively performed, LOA Holder must 

indicate full details of the calibration 

procedure, results, and any associated 

issues in the 48-hour interim reports. 

(9) The final results of SFV 

measurements from each foundation 

installation must be submitted as soon 

as possible, but no later than 90 days 

following completion of each event’s 

SFV measurements. The final reports 

must include all details prescribed 

above for the interim report as well as, 

at minimum, the following: the peak 

sound pressure level (SPLpk), the rootmean-square sound pressure level that 

contains 90 percent of the acoustic 

energy (SPLrms), the single strike sound 

exposure level (SELss), the integration 

time for SPLrms, the spectrum, and the 

24-hour cumulative SEL extrapolated 

from measurements at all hydrophones. 

The final report must also include at 

least the maximum, mean, minimum, 

median (L50) and L5 (95 percent 

exceedance) statistics for each metric; 

the SEL and SPL power spectral density 

and/or one-third octave band levels 

(usually calculated as decidecade band 

levels) at the receiver locations should 

be reported; the sound levels reported 

must be in median, arithmetic mean, 

and L5 (95 percent exceedance) (i.e., 

average in linear space), and in dB; 

range of transmission loss coefficients; 

the local environmental conditions, 

such as wind speed, transmission loss 

data collected on-site (or the sound 

velocity profile); baseline pre- and postactivity ambient sound levels 

(broadband and/or within frequencies of 

concern); a description of depth and 

sediment type, as documented in the 

Construction and Operation Plan (COP), 

at the recording and foundation 

installation locations; the extents of the 

measured Level A harassment and Level 

B harassment zone(s); hammer energies 

required for pile installation and the 

number of strikes per pile; the 

hydrophone equipment and methods 

(i.e., recording device, bandwidth/ 

sampling rate; distance from the pile 

where recordings were made; the depth 

of recording device(s)); a description of 

the SFV measurement hardware and 

software, including software version 

used, calibration data, bandwidth 

capability and sensitivity of 

hydrophone(s), any filters used in 

hardware or software, any limitations 

with the equipment, and other relevant 

information; the spatial configuration of 

the noise attenuation device(s) relative 

to the pile; a description of the noise 

abatement system and operational 

parameters (e.g., bubble flow rate, 

distance deployed from the pile, etc.), 

and any action taken to adjust the noise 

abatement system. A discussion which 

includes any observations which are 

suspected to have a significant impact 

on the results including but not limited 

to: observed noise mitigation system 

issues, obstructions along the 

measurement transect, and technical 

issues with hydrophones or recording 

devices. 

(10) If at any time during the project 

LOA Holder becomes aware of any issue 

or issues which may (to any reasonable 

subject-matter expert, including the 

persons performing the measurements 

and analysis) call into question the 

validity of any measured Level A 

harassment or Level B harassment 

isopleths to a significant degree, which 

were previously transmitted or 

communicated to NMFS Office of 

Protected Resources, LOA Holder must 

inform NMFS Office of Protected 

Resources within 1 business day of 

becoming aware of this issue or before 

the next pile is driven, whichever comes 

first. 

(11) If a North Atlantic right whale is 

acoustic detected at any time by a 

project-related PAM system, LOA 

Holder must ensure the detection is 

reported as soon as possible to NMFS, 

but no longer than 24 hours after the 

detection via the ‘‘24-hour North 

Atlantic right whale Detection 

Template’’ (https://

www.fisheries.noaa.gov/resource/ 

document/passive-acoustic-reportingsystem-templates). Calling the hotline is 

not necessary when reporting PAM 

detections via the template. 

(12) Full detection data, metadata, 

and location of recorders (or GPS tracks, 

if applicable) from all real-time 

hydrophones used for monitoring 

during construction must be submitted 

within 90 calendar days after pile 

driving has ended and instruments have 

been pulled from the water. Reporting 

must use the webform templates on the 

NMFS Passive Acoustic Reporting 

System website at https://

www.fisheries.noaa.gov/resource/ 

document/passive-acoustic-reportingsystem-templates. Submit the completed 

data templates to nmfs.nec.pacmdata@

noaa.gov. The full acoustic recordings 

from all real-time hydrophones must 

also be sent to the National Centers for 

Environmental Information (NCEI) for 

archiving within 90 calendar days 

following completion of activities 

requiring PAM for mitigation. 

Submission details can be found at: 

https://www.ncei.noaa.gov/products/ 

passive-acoustic-data. 

(13) LOA Holder must submit 

situational reports if the following 

circumstances occur (including all 

instances wherein an exemption is 

taken must be reported to NMFS Office 

of Protected Resources within 24 hours): 

(i) If a North Atlantic right whale is 

observed at any time by PSOs or project 

personnel, LOA Holder must ensure the 

sighting is immediately (if not feasible, 

as soon as possible, and no longer than 

24 hours after the sighting) reported to 

NMFS and the Right Whale Sightings 

Advisory System (RWSAS). If in the 

Northeast Region (Maine to Virginia/ 

North Carolina border) call (866–755– 

6622). If in the Southeast Region (North 

Carolina to Florida) call (877–WHALE– 

HELP or 877–942–5343). If calling 

NMFS is not possible, reports can also 

be made to the U.S. Coast Guard via 

channel 16 or through the WhaleAlert 

app (https://www.whalealert.org). The 

sighting report must include the time, 

date, and location of the sighting, 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
586 Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 

number of whales, animal description/ 

certainty of sighting (provide photos/ 

video if taken), Lease Area/project 

name, PSO/personnel name, PSO 

provider company (if applicable), and 

reporter’s contact information. 

(ii) If a North Atlantic right whale is 

observed at any time by PSOs or project 

personnel, LOA Holder must submit a 

summary report to NMFS GARFO 

(nmfs.gar.incidental-take@noaa.gov) 

and NMFS Office of Protected 

Resources, and NMFS Northeast 

Fisheries Science Center (NEFSC; 

ne.rw.survey@noaa.gov) within 24 hours 

with the above information and the 

vessel/platform from which the sighting 

was made, activity the vessel/platform 

was engaged in at time of sighting, 

project construction and/or survey 

activity at the time of the sighting (e.g., 

pile driving, cable installation, HRG 

survey), distance from vessel/platform 

to sighting at time of detection, and any 

mitigation actions taken in response to 

the sighting. 

(iii) If an observation of a large whale 

occurs during vessel transit, LOA 

Holder must report the time, date, and 

location of the sighting; the vessel’s 

activity, heading, and speed (knots); 

Beaufort sea state, water depth (meters), 

and visibility conditions; marine 

mammal species identification to the 

best of the observer’s ability and any 

distinguishing characteristics; initial 

distance and bearing to marine mammal 

from vessel and closest point of 

approach; and any avoidance measures 

taken in response to the marine 

mammal sighting. 

(iv) In the event that personnel 

involved in the Project discover a 

stranded, entangled, injured, or dead 

marine mammal, LOA Holder must 

immediately report the observation to 

NMFS. If in the Greater Atlantic Region 

(Maine to Virginia) call the NMFS 

Greater Atlantic Stranding Hotline (866– 

755–6622); if in the Southeast Region 

(North Carolina to Florida), call the 

NMFS Southeast Stranding Hotline 

(877–942–5343). Separately, LOA 

Holder must report the incident to 

NMFS Office of Protected Resources 

(PR.ITP.MonitoringReports@noaa.gov) 

and, if in the Greater Atlantic region 

(Maine to Virginia), NMFS GARFO 

(nmfs.gar.incidental-take@noaa.gov, 

nmfs.gar.stranding@noaa.gov) or, if in 

the Southeast region (North Carolina to 

Florida), NMFS Southeast Regional 

Office (SERO; secmammalreports@

noaa.gov) as soon as feasible. The report 

(via phone or email) must include 

contact (name, phone number, etc.), the 

time, date, and location of the first 

discovery (and updated location 

information if known and applicable); 

species identification (if known) or 

description of the animal(s) involved; 

condition of the animal(s) (including 

carcass condition if the animal is dead); 

observed behaviors of the animal(s), if 

alive; if available, photographs or video 

footage of the animal(s); and general 

circumstances under which the animal 

was discovered. 

(v) In the event of a vessel strike of a 

marine mammal by any vessel 

associated with the Project or if other 

project activities cause a non-auditory 

injury or death of a marine mammal, 

LOA Holder must immediately report 

the incident to NMFS. If in the Greater 

Atlantic Region (Maine to Virginia) call 

the NMFS Greater Atlantic Stranding 

Hotline (866–755–6622) and if in the 

Southeast Region (North Carolina to 

Florida) call the NMFS Southeast 

Stranding Hotline (877–942–5343). 

Separately, LOA Holder must 

immediately report the incident to 

NMFS Office of Protected Resources 

(PR.ITP.MonitoringReports@noaa.gov) 

and, if in the Greater Atlantic region 

(Maine to Virginia), NMFS GARFO 

(nmfs.gar.incidental-take@noaa.gov, 

nmfs.gar.stranding@noaa.gov) or, if in 

the Southeast region (North Carolina to 

Florida), NMFS SERO 

(secmammalreports@noaa.gov). The 

report must include the time, date, and 

location of the incident; species 

identification (if known) or description 

of the animal(s) involved; vessel size 

and motor configuration (inboard, 

outboard, jet propulsion); vessel’s speed 

leading up to and during the incident; 

vessel’s course/heading and what 

operations were being conducted (if 

applicable); status of all sound sources 

in use; description of avoidance 

measures/requirements that were in 

place at the time of the strike and what 

additional measures were taken, if any, 

to avoid strike; environmental 

conditions (e.g., wind speed and 

direction, Beaufort sea state, cloud 

cover, visibility) immediately preceding 

the strike; estimated size and length of 

animal that was struck; description of 

the behavior of the marine mammal 

immediately preceding and following 

the strike; if available, description of the 

presence and behavior of any other 

marine mammals immediately 

preceding the strike; estimated fate of 

the animal (e.g., dead, injured but alive, 

injured and moving, blood or tissue 

observed in the water, status unknown, 

disappeared); and to the extent 

practicable, photographs or video 

footage of the animal(s). LOA Holder 

must immediately cease all on-water 

activities until the NMFS Office of 

Protected Resources is able to review 

the circumstances of the incident and 

determine what, if any, additional 

measures are appropriate to ensure 

compliance with the terms of the LOA. 

NMFS Office of Protected Resources 

may impose additional measures to 

minimize the likelihood of further 

prohibited take and ensure MMPA 

compliance. LOA Holder may not 

resume their activities until notified by 

NMFS Office of Protected Resources. 

(14) LOA Holder must report any lost 

gear associated with the fishery surveys 

to the NOAA GARFO Protected 

Resources Division (nmfs.gar.incidentaltake@noaa.gov) as soon as possible or 

within 24 hours of the documented time 

of missing or lost gear. This report must 

include information on any markings on 

the gear and any efforts undertaken or 

planned to recover the gear. 

§ 217.346 Letter of Authorization. 

(a) To incidentally take marine 

mammals pursuant to this subpart, LOA 

Holder must apply for and obtain an 

LOA. 

(b) The LOA, unless suspended or 

revoked, may be effective for a period of 

time not to exceed December 31, 2029, 

the expiration date of this subpart. 

(c) In the event of projected changes 

to the activity or to mitigation and 

monitoring measures required by the 

LOA, LOA Holder must apply for and 

obtain a modification of the LOA as 

described in § 217.347. 

(d) The LOA must set forth: 

(1) Permissible methods of incidental 

taking; 

(2) Means of effecting the least 

practicable adverse impact (i.e., 

mitigation) on the species, its habitat, 

and on the availability of the species for 

subsistence uses; and 

(3) Requirements for monitoring and 

reporting. 

(e) Issuance of the LOA must be based 

on a determination that the level of 

taking must be consistent with the 

findings made for the total taking 

allowable under the regulations of this 

subpart. 

(f) Notice of issuance or denial of the 

LOA must be published in the Federal 

Register within 30 days of a 

determination. 

§ 217.347 Modifications of Letter of 

Authorization. 

(a) The LOA issued under §§ 217.342 

and 217.346 or this section for the 

activity identified in § 217.340 shall be 

modified upon request by LOA Holder, 

provided that: 

(1) The proposed specified activity 

and mitigation, monitoring, and 

reporting measures, as well as the 

anticipated impacts, are the same as 


khammond on DSKJM1Z7X2PROD with PROPOSALS2
Federal Register / Vol. 89, No. 3 / Thursday, January 4, 2024 / Proposed Rules 587 

those described and analyzed for this 

subpart (excluding changes made 

pursuant to the adaptive management 

provision in paragraph (c)(1) of this 

section); and 

(2) NMFS Office of Protected 

Resources determines that the 

mitigation, monitoring, and reporting 

measures required by the previous LOA 

under this subpart were implemented. 

(b) For a LOA modification request by 

the applicant that includes changes to 

the activity or the mitigation, 

monitoring, or reporting (excluding 

changes made pursuant to the adaptive 

management provision in paragraph 

(c)(1) of this section), the LOA shall be 

modified, provided that: 

(1) NMFS Office of Protected 

Resources determines that the changes 

to the activity or the mitigation, 

monitoring, or reporting do not change 

the findings made for the regulations in 

this subpart and do not result in more 

than a minor change in the total 

estimated number of takes (or 

distribution by species or years); and 

(2) NMFS Office of Protected 

Resources may, if appropriate, publish a 

notice of proposed LOA in the Federal 

Register, including the associated 

analysis of the change, and solicit 

public comment before issuing the LOA. 

(c) The LOA issued under §§ 217.342 

and 217.346 or this section for the 

activities identified in § 217.340 may be 

modified by NMFS Office of Protected 

Resources under the following 

circumstances: 

(1) Through adaptive management, 

NMFS Office of Protected Resources 

may modify (including delete, modify, 

or add to) the existing mitigation, 

monitoring, or reporting measures (after 

consulting with the LOA Holder 

regarding the practicability of the 

modifications), if doing so creates a 

reasonable likelihood of more 

effectively accomplishing the goals of 

the mitigation and monitoring; 

(i) Possible sources of data that could 

contribute to the decision to modify the 

mitigation, monitoring, or reporting 

measures in the LOA include, but are 

not limited to: 

(A) Results from LOA Holder’s 

monitoring; 

(B) Results from other marine 

mammals and/or sound research or 

studies; and 

(C) Any information that reveals 

marine mammals may have been taken 

in a manner, extent, or number not 

authorized by the regulations in this 

subpart or subsequent LOA. 

(ii) If, through adaptive management, 

the modifications to the mitigation, 

monitoring, or reporting measures are 

substantial, NMFS Office of Protected 

Resources shall publish a notice of 

proposed LOA in the Federal Register 

and solicit public comment. 

(2) If NMFS Office of Protected 

Resources determines that an emergency 

exists that poses a significant risk to the 

well-being of the species or stocks of 

marine mammals specified in the LOA 

issued pursuant to §§ 217.342 and 

217.346 or this section, the LOA may be 

modified without prior notice or 

opportunity for public comment. Notice 

would be published in the Federal 

Register within 30 days of the action. 

§§ 217.348–217.349 [Reserved] 

[FR Doc. 2023–27189 Filed 1–3–24; 8:45 am] 

BILLING CODE 3510–22–P 


khammond on DSKJM1Z7X2PROD with PROPOSALS2