Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to Phase 2 Construction of the Vineyard Wind 1 Offshore Wind Project off Massachusetts

SUPPLEMENTARY INFORMATION:

Background

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 and either an authorized is proposed or, if the taking is limited to harassment, a notice of a proposed IHA is provided to the public for review.

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, and on the availability of the species or stocks for taking for certain subsistence uses (referred to in shorthand as “mitigation”); and requirements pertaining to the monitoring and reporting of the takings. The definitions of all applicable MMPA statutory terms cited above are included in the relevant sections below.

Summary of Request

On December 15, 2023, NMFS received a request from Vineyard Wind 1 for an IHA to take marine mammals incidental to Phase 2 construction of the Vineyard Wind 1 Offshore Wind Project off Massachusetts, specifically wind turbine generator (WTG) monopile foundation installation, in the northern portion of Lease Area OCS-A 0501. Vineyard Wind 1 completed installation of 47 WTG monopiles and one electrical service platform (ESP) jacket foundation in 2023 under an IHA issued by NMFS on June 25, 2021 (86 FR 33810) with effective dates from May 1, 2023 through April 30, 2024. Due to unexpected delays, Vineyard Wind 1 was not able to complete pile driving activities before the expiration date of the current IHA (April 30, 2024); thus, Vineyard Wind 1 requested take of marine mammals incidental to installing the remaining 15 monopiles to complete foundation installation for the Project. In total, the Project will consist of 62 WTG monopiles and 1 offshore substation.

Following NMFS' review of the December 2023 application, Vineyard Wind 1 submitted multiple revised versions of the application, and it was deemed adequate and complete on March 13, 2024. The Vineyard Wind 1 request was for take of 14 species of marine mammals, by Level B harassment and, for 6 of these species, Level A harassment. Neither Vineyard Wind 1 nor NMFS expect serious injury or mortality to result from this activity and, therefore, an IHA is appropriate.

Vineyard Wind 1 previously conducted high resolution geophysical (HRG) site characterization surveys within the Lease Area and associated export cable corridor in 2016, 2018-2021, and during the 2023 construction season from June-December (ESS Group Inc., 2016; Vineyard Wind, 2018, 2019; EPI Group, 2021; RPS, 2022; Vineyard Wind, 2023a-f). During the 2023 construction season, NMFS coordinated closely with Vineyard Wind 1 to ensure compliance with their IHA. In a few instances, NMFS raised concerns with Vineyard Wind 1 regarding their implementation of certain required measures. NMFS worked closely with Vineyard Wind 1 throughout the construction season to course correct, where needed, and ensure compliance with the requirements ( e.g., mitigation, monitoring, and reporting) of the previous IHA. Information regarding their monitoring results may be found in the Estimated Take of Marine Mammals section.

Description of the Specified Activity

Overview

Vineyard Wind 1 plans to construct and operate an 800-megawatt (MW) wind energy facility, the Project, in the Atlantic Ocean in Lease area OCS-A 0501, offshore of Massachusetts. Altogether, the project will consist of up to 62 offshore WTGs, 1 ESP, an onshore substation, offshore and onshore cabling, and onshore operations and maintenance facilities. The onshore substation and ESP are now complete. Installation of 47 monopile foundations was completed under the previous IHA (86 FR 33810, June 25, 2021), effective from May 1, 2023 through April 30, 2024. However, due to unexpected delays, Vineyard Wind 1 was not able to complete pile driving activities before the expiration date of the IHA (April 30, 2024). Take of marine mammals, in the form of behavioral harassment and limited instances of auditory injury, may occur incidental to the installation of the remaining 15 WTG monopile foundations due to in-water noise exposure resulting from impact pile driving. The remaining 15 monopile foundations will be installed within a Limited Installation Area (LIA) (64.3 square kilometers (km² ; 15,888.9 acres)) within the Lease Area (264.4 km² (65,322.4 acres)). Installation of the remaining 15 monopile foundations is expected to occur in 2024, but could also occur in 2025.

Specific Geographic Region

The 15 remaining piles will be installed within a Limited Installation Area (LIA) occupying a portion of the Wind Development Area (WDA) within the Bureau of Ocean Energy Management (BOEM) lease area located in Federal waters off Massachusetts (figure 1). At its nearest point, the LIA is approximately 29 kilometers (km; 18.1 miles (mi)) from the southeast corner of Martha's Vineyard and a similar distance from Nantucket. Water depths in the WDA range from approximately 37-49.5 meters (m; 121-162 feet (ft)). Water depth and bottom habitat are similar throughout the Lease Area (Pyc et al., 2018). Figure 1 shows the LIA and planned locations for the remaining 15 monopiles to be installed.

A detailed description of the specific geographic region and planned construction activities is provided in the Federal Register notice for the proposed IHA (89 FR 31008, April 23, 2024). Since that time, no changes have been made to the planned activities. Therefore, a detailed description is not provided here. Please refer to that Federal Register notice for the description of the specific activities.

Comments and Responses

A notice of NMFS' proposal to issue an IHA to Vineyard Wind 1 was published in the Federal Register on April 23, 2024 (89 FR 31008). That notice described, in detail, Vineyard Wind's activities, the marine mammal species that may be affected by the activities, and the anticipated effects on marine mammals. In that notice, we requested public input on the request for authorization described therein, our analyses, the proposed authorization, and any other aspect of the notice of the proposed IHA, and requested that interested persons submit relevant information, suggestions, and comments.

During the 30-day public comment period, NMFS received 87 total comment letters, including letters from various non-governmental organizations (Seafreeze, Ltd., Rand Acoustics, LLC., Long Island Commercial Fishing Association (LICFA), Save Right Whales Coalition (SRWC), Rand Acoustics, Inc., ACK Residents Against Turbines) and members of the general public. We note that approximately 11 comment letters followed one of 2 different generic template formats, in which respondents provided comments that were identical or substantively the same. NMFS has reviewed all public comments received on the proposed issuance of the Vineyard Wind 1 Phase 2 IHA. All relevant substantive comments and NMFS' responses are provided below. Comments that are out of scope to NMFS' action of issuing the requested IHA ( e.g., comments regarding how unusual mortality events (UMEs) are determined to be closed or requests for necropsy reports; declarations on the adequacy of the previously issued IHA to Vineyard Wind) and comments indicating general support for or opposition to offshore wind construction are not relevant to the proposed action and therefore were not considered or addressed here. We also provide no response to species or statutes not relevant to our proposed action under section 101(a)(5)(D) of the MMPA. The public comments and recommendations are available online at: https://www.fisheries.noaa.gov/action/incidental-take-authorization-vineyard-wind-1-llc-construction-vineyard-wind-offshore-wind. Please see the comment submissions for full details regarding the recommendations and supporting rationale.

Modeling and Take Estimates

Comment 1: A commenter suggested that NMFS and Vineyard Wind 1 should not operate under the assumption that Level B takes do not result in injury or death. The commenter suggests that the IHA analysis is deficient as behavioral disturbance resulting from the proposed activities could result in auditory masking, disruption to navigational ability and spatial orientation, splitting of mother calf pairs, and increased stress and cortisol responses could lead to secondary deaths due to entanglements, vessel strikes, and strandings. Another commenter suggested that NMFS was authorizing take in the form of mortality and, further, stated that North Atlantic right whales are on the brink of extinction and a single additional death from construction activities could be catastrophic.

Response: NMFS disagrees with commenters that the planned pile driving activities would cause mortality or serious injury of marine mammals, and this final IHA does not authorize mortality or serious injury. The best scientific evidence available indicates that the anticipated impacts from the specified activities potentially include avoidance, cessation of foraging or communication, temporary threshold shift (TTS) and permanent threshold shift (PTS), stress, masking, etc. (as described in the Potential Effects of Specified Activities on Marine Mammals and Their Habitat section in the proposed IHA Federal Register notice (89 FR 31008, April 23, 2024). Further, as described in the NID section, there is no evidence to suggest that these authorized impacts (characterized as harassment), at the magnitude and severity anticipated to result from these activities, would lead to impacts on reproduction or survival of any individual North Atlantic right whale (NARW) or other marine mammals, much less mortality.

In addition, NMFS emphasizes that there is no evidence that noise resulting from offshore wind development-related specified activities would cause increased risk of marine vessel strikes, entanglements, or mammal strandings. NMFS acknowledges that whales may temporarily avoid the area where the specified activities occur. However, NMFS does not anticipate, based on the best available science, that whales will abandon their habitat or be displaced in a manner that would result in a higher risk of vessel strike or entanglement, as suggested by a commenter, and the commenter does not provide evidence that either of these effects should be a reasonably anticipated outcome of the specified activity. The primary activity that is anticipated to result in temporary avoidance of the otherwise used habitat is foundation installation pile driving. Not only would this activity be limited to times of year when North Atlantic right whale presence is lower, pile driving would be intermittent, and only occur for a limited time over the course of 1 year. Together, these factors further reduce the likelihood that this species would be in close enough proximity to the activity to engage in avoidance behavior to the degree it would move into an area of risk (which would be closer to shore) that it could be struck by another vessel or experience entanglement.

Comment 2: Multiple commenters have expressed general concern for impacts to marine mammals, specifically to North Atlantic right whales, indicating that there are too many takes proposed for authorization and the IHA should be put on hold until more is known about impacts of offshore wind construction activities to North Atlantic right whales. A commenter suggests that estimated take by Level A harassment for North Atlantic right whales should be analyzed as modeled exposure estimates were greater than zero. Another commenter indicates that every attempt must be made to protect North Atlantic right whale calves from the risk of TTS and that pile driving should shut down for the remainder of a day if a mother and calf were to enter a clearance or shutdown zone.

Response: NMFS appreciates the commenters' general concern for marine mammals and specifically for North Atlantic right whales and, in general, acknowledges the need for additional data regarding the impacts of offshore wind construction activities on North Atlantic right whales; but disagrees that Level A harassment of NARW will result from the activity or that the IHA should be put on hold until more is known. NMFS is required to consider the best available science when assessing potential impacts and cannot delay authorization of an IHA until additional data is available. While there was a very small amount of Level A harassment modeled, the model is conservative for both Level A harassment and Level B harassment, as it does not take into account that Vineyard Wind 1 will be required to monitor and delay or shut down pile driving activities if a North Atlantic right whale is visually sighted at any distance by the pile driving protected species observers (PSOs) or acoustically detected within the 10 km passive acoustic monitoring (PAM) clearance and shutdown zone. As described in the proposed IHA, from November 1 through December 31 (when Vineyard Wind 1 would be installing piles), if a North Atlantic right whale (not just a mother/calf pair) is detected either via real-time PAM or vessel-based surveys at any distance from the pile driving location, pile driving must be delayed until the “follow-up vessel-based survey” described in their Pile Driving Monitoring Plan has been completed. Moreover, if three or more North Atlantic right whales are observed, pile driving will be delayed until the following day. These conservative measures were included in the proposed IHA in recognition that North Atlantic right whales are more likely to be foraging in the area during November and December and that aggregations of North Atlantic right whales are more likely to remain in an area. The commenters' suggestion to delay pile driving until the next day if a mother and calf pair is observed is not warranted in November and December given the other extensive mitigation measures in place and the fact that data do not suggest mother and calf pairs remain in the area (Quintana-Rizzo et al., 2021). Delaying pile driving would extend the project later into December which could result in more impacts as whale density increases throughout the winter ( i.e., the later in December, the more whales are likely to be present). Moreover, delaying the project is not practicable as Vineyard Wind is installing the 15 remaining piles in 2024 but must cease pile driving after December 31. Given these mitigation measures and the extensive related monitoring efforts designed to detect North Atlantic right whales for mitigation, NMFS does not anticipate and has not authorized any take by Level A harassment for North Atlantic right whales. The required measures reduce the risk of TTS for any North Atlantic right whale. Accordingly, as described in the Federal Register notice for the proposed IHA (89 FR 31008, April 23, 2024), the final IHA assumes that the mitigation efforts will be effective at reducing the potential for Level A harassment calculated in the density-based models as, specifically, the small number of instances in which a North Atlantic right whale was modeled to approach pile driving at a distance associated with exposure above the Level A harassment threshold, would not be expected to occur given the anticipated effectiveness of clearance and shutdowns in preventing exposure at notably greater distances and lower levels. We also note that while the scientific literature documents marine mammals are likely to avoid loud noises such as pile driving ( e.g., Brandt et al., 2016; Nowacek et al., 2004), avoidance was not quantitatively considered in the take estimates (although NMFS reasonably predicts this natural behavior will further reduce the potential for Level A harassment). NMFS recognizes that the key to effective mitigation is effective monitoring and the ability to detect marine mammals so that mitigation measures, such as delay to commencement of pile driving and shutdown should pile driving be occurring, may be implemented. Vineyard Wind 1 is required to undertake extensive monitoring to maximize the ability to detect marine mammals with at least 9 PSOs monitoring for marine mammals before, during, and after pile driving. The reduction to the Level A harassment density-based take estimate appropriately reflects and acknowledges the monitoring and mitigation efforts, including the placement of three PSOs on the pile driving platform and dedicated PSOs vessel(s) and PAM.

Comment 3: A commenter indicates that estimated take by Level B harassment for common dolphins should not be adjusted per the AMAPPS average group size (30 dolphins), but rather per the PSO data collected by Vineyard Wind 1 during HRG surveys (10 dolphins) as this PSO data is more appropriate. The commenter further notes that there is no information indicating that Vineyard Wind 1 had difficulty staying within the take limits for common dolphins for the 2023 IHA.

Response: NMFS disagrees that an average group size estimate of 10 for common dolphins, based upon local PSO data, is more appropriate for adjusting the estimated take by Level B harassment for common dolphins than the AMAPPS group size of 30. The commenter references PSO data collected by Vineyard Wind 1 during HRG surveys, yet does not provide detail on the PSO report(s) upon which this data is based upon. The most recent Vineyard Wind 1 PSO report describes sighting 29 groups and a total of 717 common dolphins during the 2023 construction period, with an average group size of 24.7 dolphins (RPS, 2024). This estimate closely aligns with the average group size of 30 common dolphins from the AMAPPS dataset (Palka et al., 2017; 2021), which NMFS has determined to be the best available data and most robust dataset for adjusting take estimates due to the standardized consistent effort and large dataset sample size. The large sample size contained in the AMAPPS dataset accounts for any variability in group size that may occur between observed common dolphin groups. Therefore, NMFS has determined that the AMAPPS average group size of 30 is most appropriate for adjusting take by Level B harassment for common dolphins in this analysis.

Comment 4: Multiple commenters suggest that NMFS should consider exposure to noise from vessel propulsion, thrusters, and jet trenching with scour protection as constituting behavioral harassment or that NMFS should undertake an analysis identifying the potential for take by Level B harassment from operating offshore wind construction vessels, including the use of dynamic positioning (DP) thrusters, and jet trenching, and scour protection.

Response: NMFS analyzed the potential for various sources of noise to result in take of marine mammals and concludes that take from vessel propulsion, DP thrusters and jet trenching during Vineyard Wind 1's activities is not likely. Further, as noted below in Comment 5, mitigation requirements to further lessen any potential for impacts are included. On July 29, 2024, Vineyard Wind 1 confirmed to NMFS that scour protection activities are complete for the project and therefore this activity is not discussed further.

On a typical foundation, WTG, and inter-array cable installation day, Project vessels within and around the Lease Area may include a heavy lift pile installation vessel (the Orion), two Big Bubble Curtain (BBC) support vessels, two safety vessels, two crew transfer vessels, two accommodation vessels, one jack-up vessel installing monopile foundations, one pipe-burying vessel installing array cables, and one service operating vessel supporting foundation installation. During pile driving operations with favorable weather conditions, the Orion thrusters typically operate at approximately 25 percent capacity with a maximum capacity (1100 kW/4,500 kW). Thrusters may operate at higher capacity during higher wind speeds, waves, and currents.

In general, the Orion would be positioned at each pile driving location until after the pile is installed, after which time it would slowly transit at 10 kn (11.5 mph) or less (per the Construction and Operations Plan (COP) condition that vessels within the wind development area must travel at 10 kn (11.5 mph) or less at all times) to the next site. Because operating thrusters is inefficient with respect to cost due to fuel usage, the thrusters are typically engaged only when necessary to maintain position at the pile site or for safety reasons ( e.g., during rough weather).

Inter-array cables would be buried using a jet trencher. Noise emitted by jet trenching activities is broadband and generally consistent with that produced from routine vessel operations (Nedwell et al., 2003).

NMFS' generalized 120-dB acoustic threshold for exposures to continuous noise is guidance to help predict when marine mammals will likely respond in a manner that constitutes Level B harassment and estimate how many marine mammals are likely to respond in that manner; contrary to the suggestion of the commenter, it is not something that NMFS needs to “enforce.” As described in the proposed IHA notice, NMFS generally predicts that marine mammals are likely to be affected in a manner considered to be Level B harassment when exposed to underwater anthropogenic noise above 120 dB (RMS SPL) for continuous sources ( e.g., vessel noise considered here). However, contextual factors and qualitative parameters play an important role in determining the potential for take and should be considered as well when determining the likelihood of incidental take. As described in the proposed IHA notice, the potential for behavioral response to an anthropogenic source can be highly variable and context-specific (Ellison et al., 2012). In addition to received sound level, factors such as activity state, the novelty of a sound, and distance between the sound source and the receiver may influence whether an animal exhibits a behavioral response (Ellison et al., 2012). As NMFS has previously articulated, there are situations in which other contextual factors may appropriately support a determination that take is unlikely, even if an animal is exposed to levels above the behavioral harassment threshold.

NMFS acknowledges that, in limited cases, take of marine mammals by Level B harassment has been authorized incidental to vessel-related activities such as tugging and positioning activities that emit continuous noise into the underwater environment for extended periods of time ( e.g., 87 FR 62364, October 14, 2022). However, in recent cases where NMFS authorized take for these activities, the take was requested by an applicant and NMFS made a case-specific decision based on the specific circumstances, explaining the conservative nature of the analysis and/or discussing specific factors other than the received level alone that contributed to the decision. In the cited case, for example, NMFS considered the potential for Level B harassment from tugging and positioning activities in a concentrated area for an extended period of time, in an area inhabited by a small resident stock of marine mammals in a fairly enclosed body of water (Cook Inlet), and authorized take, by Level B harassment, for tugging and positioning activities.

While NMFS recognizes elevated noise levels from vessels, the determination of whether harassment occurs in response to exposure to activities other than pile driving is based on several factors. Monitoring reports received under earlier take authorizations show few, if any, behavioral responses during activities involving thruster use and other broadband or continuous construction noises similar to noise levels at or below typical vessel levels. For example, during the Neptune Liquefied Natural Gas (LNG) pipeline operations project in Massachusetts Bay from July 1, 2009, through June 30, 2010, twenty-six marine mammals were sighted, and twenty of these marine mammals entered the Level B harassment zone while construction activities, including thruster use, were taking place. None of the marine mammals observed within the Level B harassment zone exhibited “any modifications to their behavior that could be directly and definitively related to the construction activities” (ECOES Consulting, Inc., 2010). In 2015, Northeast Gateway L.P., (Northeast Gateway) requested take by Level B harassment incidental to Deepwater port repair activities occurring in Massachusetts Bay, including active use of DP thrusters. NMFS authorized the requested take incidental to the specified activities. The only two marine mammal sightings that occurred during the effective period of the authorization took place while vessels were actively using thrusters, and no behaviors that would suggest harassment were observed (TetraTech, 2017).

NMFS acknowledges that noise emitted by Vineyard Wind project-related vessels and their DP thrusters, as well as jet trenching activities, may sometimes result in marine mammals being exposed to received levels above 120 dB and that vessel noise impacts the soundscape. However, as described in the Behavioral Effects section of the Potential Effects of Specified Activities on Marine Mammals and their Habitat of the proposed IHA notice, the likelihood of Level B harassment is not based upon received level alone. There are a variety of studies (Nowacek et al., 2004; Kastelein et al., 2012 and 2015) indicating that contextual variables play a very important role in response to anthropogenic noise, and the severity of effects are not necessarily linear when compared to a received level (RL). Nowacek et al. (2004) found that North Atlantic right whales exposed to alert signals and approaching vessel sounds exhibited a variety of responses. While 5 of the 6 whales altered their behavior in response to the alert signal, the whales did not exhibit a response to a vessel noise recording which simulated a 120 m container ship passing within 100 meters (m), equating to approximately 135 dB received level, or the noise of transiting vessels passing within 1 nautical mile (nm) from the whales (Nowacek et al., 2004). During Vineyard Wind 1's 2023 construction activities (RPS, 2024), PSOs observed more baleen whales, engaged in various activity states, in the Project Area while the impact hammer was off (77 detection events) than when it was on (22 detection events), although multiple vessels and DP thrusters were present and likely engaged while the impact hammer was off. These observations suggest that noise emitted from vessels, including those operating DP thrusters and jet trenching activities, is notably less likely to elicit avoidance and other behavioral responses from marine mammals that constitute Level B harassment. Given marine mammal exposure to extensive vessel traffic in the Atlantic Ocean, including from major ports and major shipping lanes near the project site, habituation to similar noise from vessels, thrusters, and trenching may be expected. As described in the proposed IHA notice, 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) as is typically considered the case with exposure to noise from vessel propulsion, noting that the typical predictable movement and operation of vessels also influences the lower likelihood of behavioral disturbance. In the case of the Vineyard Wind 1 Project, the marine mammal species potentially affected by the project inhabit areas subject to very high, consistent ship traffic (Hatch et al., 2008; Van Parijs et al., 2023).

Based on the available data, project-related vessels, including those operating thrusters, are not significantly louder than large cargo vessels marine mammals in the project area are accustomed to encountering. The median rms sound pressure level (SPL) measured at a range of 750 m from the piling (the Orion), and support vessels prior to pile driving of the first 13 piles from the Vineyard Wind 1 2023 construction activities measured approximately 134 dB (Küsel et al., 2024 Nedwell et al. (2003) backcalculated SPL source levels for jet trenching activities to be 178 dB, assuming a propagation loss of 22logR and recording 160 m from trenching activity. A reasonable estimate for source level of a container ship, estimated from the bulk data of MacGillivray and de Jong (2021), is approximately 180 dB. Using practical spreading, this source level yields approximately 137 dB at a range of 750 m.

Although lack of detected behavioral disruption during previous monitoring described above does not prove there are no undetected responses that may qualify as Level B harassment, these findings clearly suggest that marine mammals continue their regular behavior patterns in the presence of vessels, including those operating DP thrusters for the project. In consideration of the discussion above, we conclude that exposure to vessel noise for this Project, including from DP thrusters and trenching activities, is not likely to result in Level B harassment simply based on exposure above the 120 dB threshold.

Comment 5: Commenters suggest the NMFS should mitigate for behavioral take that may occur incidental to exposure to noise from vessels, thrusters, and trenching that exceed NMFS' behavioral harassment threshold for continuous noise (120 dB rms).

Response: As described in Comment 4, NMFS disagrees that exposure to vessel noise from the Project, including from DP thrusters and trenching activities, is likely to result in take under the MMPA (see response to Comment 4 above). However, NMFS does agree that vessel quieting, in general, is an important tool for protecting marine species and acoustic habitat. Vineyard Wind has committed to minimally use DP thrusters such that unnecessary use of thrusters and emission of continuous noise into the underwater environment is avoided. In addition, Vineyard Wind is required to abide by any existing vessel speed regulations as well as vessel strike avoidance measures in the IHA. When vessels are required to maintain a 10 knot (kn) (11.5 mph) speed restriction (see Vessel Strike Avoidance Measures in the Mitigation section), continuous noise released into the environment from the vessels is also reduced. The relationship between vessel speed and its associated underwater radiated noise is well established and it is generally assumed that noise levels depend on vessel speed as 60 log10(V) (MacGillivray and de Jong, 2021), where V is the vessel speed. Further, speed limitations have been shown to be an effective tool in mitigation, as even small speed reductions of many vessels are capable of substantially reducing noise impacts to marine mammals (Findlay et al., 2023).

Comment 6: Commenters note that it is inappropriate for Vineyard Wind 1 to estimate its own impacts, analyze its own impacts, and then restrict IHA public document estimates to what it has determined to be appropriate.

Response: NMFS disagrees that the process of Vineyard Wind 1 estimating and analyzing impacts of the proposed construction activity is inappropriate. NMFS' implementing regulations require applicants to include in their request a detailed description of the specified activity or class of activities that can be expected to result in incidental taking of marine mammals, 50 CFR 216.104(a)(1), as well as an analysis of the impacts of the activity on marine mammal species or stocks and their habitat. Thus, the “specified activity” for which incidental take coverage is being sought under section 101(a)(5)(D) is generally defined and described by the applicant. NMFS evaluates the applicant's analysis using the best available information and makes the necessary findings and determinations on how the proposed activities may impact marine mammals, their habitats, and availability of marine mammals for subsistence uses, if relevant. As indicated in the proposed IHA, based on our independent evaluation, NMFS concurred with the analysis methods and results presented by Vineyard Wind 1 and carried them forward in the proposed IHA. NMFS is required to post proposed IHAs for public comment in addition to supporting information. NMFS also posts all monitoring reports (including any past monitoring reports for past authorizations) on our website: https://www.fisheries.noaa.gov/national/marine-mammal-protection/incidental-take-authorizations-other-energy-activities-renewable. As the required documentation mentioned above has been posted for the Vineyard Wind IHA request, NMFS disagrees that “IHA public documents” have been restricted.

Comment 7: Commenters request that the pile driving noise model, with all assumptions, be made public along with any technical information relevant to the initial noise exceedances during pile driving in 2023.

Response: Relevant information on how the pile driving noise model works, assumptions, and technical information related to sound field verification (SFV) results were publicly available. Of note, only the modeled distances to the Level A harassment thresholds were applied to this IHA; the distance to the Level B harassment threshold is based on in situ data collected during foundation installation in 2023. A description of the pile driving source and propagation models used to estimate distances to PTS thresholds was made publicly available as an appendix within the Vineyard Wind 1 Construction and Operations Plan (COP), in the form of an acoustic modeling report (Pyc et al., 2018) and is available online as Appendix III in the COP at: https://www.boem.gov/sites/default/files/renewable-energy-program/State-Activities/MA/Vineyard-Wind/Vineyard-Wind-COP-Volume-III-Appendix-III-M.pdf. While source and propagation models are proprietary (most developed by JASCO) and not available to the public, Appendix A of Pyc et al. (2018) includes references describing their theory of calculation. Technical information and results related to SFV conducted during pile driving in 2023, upon which the Level B threshold analysis for the current IHA is based, are also publicly available on NMFS' website.

Comment 8: Commenters indicate that NMFS and Vineyard Wind 1 have underestimated both impulsive and continuous noise levels and suggest that the actual exposure to noise levels from pile driving is greater than NMFS acknowledges in its existing protective measures. Commenters request that NMFS conduct a reassessment of RMS computation methods.

Response: NMFS disagrees with the commenters that noise levels are underestimated and a reassessment of RMS computation methods is necessary. NMFS continuously assesses its analysis based on new science, including acceptable and ideal methods for calculating underwater sound metrics. Our current methodology is to use a 90 percent energy window for computing RMS sound pressure levels for impulsive sources (Madsen, 2005). The 90 percent energy envelope used by NMFS is a commonly used convention (Merchant et al., 2015), and is even stated as the recommended energy window in the ISO standard `Underwater acoustics—Measurement of radiated underwater sound from percussive pile driving' (ISO 18406, 2017). Importantly, the distance to the Level B threshold is based upon in situ SFV measurements, and not modeling. Finally, there is no take expected or authorized from continuous sources.

Comment 9: A commenter notes that condition 3(b) of the proposed IHA indicates that no take by Level A harassment is authorized, however, proposed take by Level A harassment is listed for species in table 1.

Response: NMFS appreciates the commenter's recognition that take by Level A harassment was included in table 1 yet not described in condition 3(b) of the IHA. This inconsistency has been corrected in the final IHA.

Mitigation

Comment 10: Multiple commenters stated that bubble curtains are not an efficient mitigation measure as bubble curtains do not attenuate sounds at lower frequencies and therefore are not effective in preventing take by Level A harassment of North Atlantic right whales. A commenter further indicated that this lack of mitigation should be incorporated into take calculations. Commenters also cite seabed refraction as a mechanism for sound to circumvent bubble curtains and impact marine mammals, thus resulting in the use of bubble curtains being insufficient as a mitigation measure. Commenters further note that since bubble curtains will be used as a mitigative measure yet are not effective for mitigation, NMFS will not be able to measure impacts to ESA-listed baleen whale species.

Response: In the Federal Register notice for the proposed IHA (89 FR 31008, April 23, 2024), NMFS described the best available science, which supports the assumption that attenuation can be reliably achieved using noise attenuation systems such as a double bubble curtain. The commenters indicated that sound may circumvent bubble curtains (such as through seabed refraction), citing Rand (2023). NMFS agrees that attenuation levels vary by frequency band and that bubble curtains attenuate higher frequency sounds more effectively; however, NMFS disagrees that lower frequency bands, which are important to consider when evaluating impacts, are not attenuated at all. The data from Bellmann (2021) shows that for both single and double bubble curtains, more than 10 dB of attenuation was achieved for bands as low as 32 Hz. While it is true that performance diminishes significantly at lower frequencies (<32 Hz), those bands also contain significantly less pile driving sound and are 16+ dB outside the most susceptible frequency range for low-frequency cetaceans. NMFS agrees that a fraction of the sound does travel through the sediment and rejoin the water column beyond the extent of the bubble curtain, and therefore is not attenuated by the bubble curtain. NMFS is not aware of any noise mitigation system available which directly deals with sediment-borne noise. Despite this limitation, bubble curtains have been shown to be highly effective in mitigating sound in the water column (Bellmann, 2021; Caltrans, 2020).

Comment 11: One commenter notes that while the proposed IHA includes language about soft starts as a mitigation measure, there is no evidence for the efficacy of this measure. The commenter further notes that the Vineyard Wind 1 Biological Opinion states that there is insufficient evidence that the soft start measure would alter take estimates.

Response: NMFS disagrees with the commenter that there is no evidence for the efficacy of soft start as a mitigation measure, and also notes that the soft start measure was not used as a basis for altering take estimates. A soft start, in which an initial set of hammer strikes is performed at a reduced energy level, is designed to provide a warning to marine mammals and a chance to leave the pile driving area before the hammer begins operating at full capacity. The soft start method has been found to reduce the cumulative sound exposure of animals in an area (Ainslie and von Benda-Beckmann, 2012). Ainslie and von Benda-Beckmann (2012) modeled the efficacy of the soft start method and found that soft start can be an effective mitigation measure when the animals respond to the sound source by swimming away. Various species of marine mammals have been observed to behaviorally respond to soft starts (also called ramp-ups) such that the risk of PTS and TTS is decreased ( e.g., Stone et al., 2017) and modeling studies have demonstrated similar effectiveness (von Benda Beckmann, et al., 2013). As described in the Potential Effects of Specified Activities on Marine Mammals and their Habitat in the Federal Register notice of the proposed IHA, marine mammals may avoid areas of impact pile driving ( e.g., Tougaard et al., 2009; Dähne et al., 2013; Thompson et al., 2013; Russell et al., 2016; Brandt et al., 2018).

Also, the Biological Opinion specifies that while NMFS is “not able to predict the extent to which the soft start will reduce the number of whales exposed to pile driving noise or the extent to which it will reduce the duration of exposure. Therefore, while the soft start is expected to reduce effects of pile driving, we are not able to modify the estimated take numbers to account for any benefit provided by the soft start.” This language appropriately expresses the expected benefits of soft start, while acknowledging that they are difficult to quantify, which is why there are no adjustments to take numbers based on the fact that soft start is required.

Comment 12: Multiple commenters cite the Rand Acoustics report (Rand, 2024) as calculating acoustic impacts greater than estimated by Vineyard Wind 1 and indicating the need for larger clearance zones. Rand Inc., (2024) asserts that pile driving noise rivals the loudness and frequency range of seismic air gun arrays. Commenters claim that the proposed clearance and shutdown zones are insufficient to effectively reduce impacts to marine mammals because sound exposure, in terms of impulsive and continuous noise levels, is underestimated. Commenters indicate that more research on marine mammal avoidance of impulsive sound should be incorporated into the analysis to determine how to expand mitigation zones, and that the current mitigation zones for endangered species are not large enough. One commenter further notes without justification that all mitigation zones, as well as clearance and shutdown procedures, proposed for North Atlantic right whales should be applicable to all endangered marine mammal species, specifically the sperm whale, fin whale, and sei whale.

Response: NMFS reviewed the Rand Inc. (2024) report and found that the initial modeling done for Vineyard Wind 1 considered source levels reasonably consistent with both Rand's results and the Vineyard Wind 1 2023 SFV report. The extensive measurements performed during the 2023 IHA for Vineyard Wind 1 construction allowed NMFS an opportunity to review data collected at several distances from the source. Based on those data, NMFS has determined that the distances to the Level A and Level B harassment thresholds (and any associated mitigation zones) during the 2024 Phase 2 pile installation activities are reasonable estimates based on the best available science. The results show that for Level A harassment, the model predicted acoustic ranges were on average conservative. Therefore, considerations related to Level A take based on the initial modeling were validated by the 2023 SFV campaign. For Level B, the IHA analysis here was based directly on applicable measurements from the 2023 campaign. Thus, with regard to impact pile driving, NMFS's acoustic ranges and take estimates are well supported by extensive field measurements, are consistent with the data presented in Rand (2024), and therefore do not warrant revisions.

NMFS disagrees that expanded shutdown and clearance zones are necessary under the least practicable adverse impact standard for marine mammal species or stocks, including those listed under the ESA. As described in the Proposed Mitigation section in the Federal Register notice for the proposed IHA and the Mitigation section of this notice, there is a required shutdown if a North Atlantic right whale is visually observed at any distance or acoustically detected within the 10 km PAM monitoring zone. In addition, impact pile driving may not begin if a North Atlantic right whale is visually sighted or acoustically detected within the pre-start clearance zone at any distance during the 30-minute clearance period. NMFS neither anticipates nor authorizes any take by Level A harassment of North Atlantic right whales.

Some mitigation measures in the IHA are centered around North Atlantic right whales because of the species status and general fitness of individuals. NMFS acknowledges that seasonal closures are based on North Atlantic right whale densities and that the maximum density months for other ESA-listed species may occur outside of the seasonal closures. Other enhanced mitigation for North Atlantic right whales includes delaying or shutting down pile driving should a North Atlantic right whale be observed at any distance by a foundation installation PSO or acoustically detected within the PAM monitoring zone. If clearance and shutdown zones were increased for other ESA-listed species, it would result in longer construction time frames, prolonging the time periods over which marine mammals may be exposed to construction-related stressors, as well as creating impracticable operational scenarios for the applicant. It has been modeled and is logical that projects should be constructed as quickly as possible during times when the potential for a species of concern to be present is lowest (Southall et al. 2021). Accordingly, NMFS has determined that the current clearance and shutdown zones together with other mitigation measures effect the least practicable adverse impact on the affected species or stocks of marine mammals.

Comment 13: A commenter states that the proposed shutdown procedures are not strict enough and should be more comparable to oil/gas authorizations that require shutdown for live marine mammal strandings and “millings within 50 km of survey operations.”

Response: NMFS agrees that the addition of the measure the commenter recommended is appropriate and has added a measure to the IHA for Vineyard Wind 1 to cease pile driving in the event of a live cetacean stranding (or near-shore atypical milling) event within 50 km of the pile driving operations, where the NMFS Marine Mammal Stranding Network is engaged in herding or other interventions to return animals to the water.

Comment 14: While commenters acknowledge that time of year restrictions on pile driving are effective mitigation measures, multiple commenters suggested that the proposed seasonal restrictions are insufficient as the restriction period does not account for North Atlantic right whales, sperm whales, and fin whales in the Project Area outside of those months. Commenters further note that endangered marine mammal species are present in the Project Area year-round, especially North Atlantic right whales during the late summer.

Response: NMFS has restricted foundation installation pile driving from January through May, which represents the period when North Atlantic right whales are most likely to be in the Project Area in higher numbers and engaged in foraging behavior. A commenter indicated that the seasonal restriction period of January through May does not account for the heightened presence of North Atlantic right whales in southern New England during the late summer (Quintana-Rizzo et al., 2021). However, North Atlantic right whale presence during the summer is typically closer to Nantucket Shoals (Quintana-Rizzo et al., 2021; Van Parijs et al., 2023) and not concentrated within the lease area or the LIA. In addition, North Atlantic right whale densities are highest in the lease area and LIA from January through May (Roberts et al., 2023), further supporting that period as an appropriate time frame for implementing seasonal restrictions for North Atlantic right whales. NMFS acknowledges that seasonal closures are based on North Atlantic right whale densities and the maximum density months for other ESA-listed species, such as fin whales and sperm whales, and stocks experiencing UMEs, such as minke whales, may occur outside of the seasonal closures (table 9). However, no UMEs are active for ESA-listed marine mammals other than the North Atlantic right whale and there is other mitigation for those species. See Comment 12 for additional detail on implementing additional mitigation measures for Endangered Species Act (ESA)-listed and species and stocks experiencing UMEs.

Seasonal restrictions are not in place from June through December because North Atlantic right whale densities are lower. During those months pile driving may take place, Vineyard Wind 1 is required to implement mitigation measures during pile driving to reduce impacts to marine mammals. These mitigation measures include clearance and shutdown zones, visual and acoustic monitoring of zones by PSOs and PAM operators, and use of noise attenuation devices to reduce impacts to marine mammals. These measures are consistent with those required and successfully implemented under previous incidental take authorizations, as described in the Mitigation section. Furthermore, VW1 is required to establish stronger mitigation measures for endangered species, such as fin whales and sperm whales; for example those species have larger clearance and shutdown distances than other marine mammals.

During November and December, Vineyard Wind 1 will be required to follow enhanced mitigation measures if impact pile driving occurs. From November 1-December 31, if pile driving has been shut down or delayed due to the presence of 3 or more North Atlantic right whales, pile driving will be postponed until the next day. As December represents the highest density month for North Atlantic right whale outside of the January through May restriction, Vineyard Wind 1 will be required to follow additional enhanced measures beyond those required in November. In December, Vineyard Wind 1 must conduct, in addition to PAM, extended surveys using the dedicated PSOs vessels prior to starting or resuming pile driving as described in their Pile Driving Monitoring Plan. With the application of these enhanced mitigation and monitoring measures in November and December, impacts to NARW will be further reduced. Accordingly, NMFS has determined that the seasonal restrictions, together with other mitigation measures, effect the least practicable adverse impact on marine mammals.

Comment 15: One commenter claims that as more research is needed on marine mammal hearing, the precautionary principle should be employed by expanding mitigation zones, increasing accountability of vessel operators to offshore wind vessels, applying more checks and balances to those conducting construction activities, and reviewing vessel transcripts. The commenter specifically states that limited data on PTS onset thresholds as a result of data coming from the same species and/or same captive animals results in dependent data sets, and requests that 6 month moratorium be placed on all east coast wind projects until detailed study can be conducted by independent researchers.

Response: MMPA and its implementing regulations require that IHAs be issued based on the best scientific evidence available, if the required findings can be made. NMFS agrees with the commenter that additional research will continue to improve our understanding of the impacts of anthropogenic noise on marine mammal hearing, yet disagrees that expanded mitigation and monitoring measures or a moratorium on east coast wind projects are necessary under the least practicable adverse impact standard. See Comment 26 for details on data related to PTS onset thresholds. The IHA includes general conditions to hold Vineyard Wind 1 and its designees (including vessel operators and other personnel) accountable while performing operations under this IHA. In addition to requiring Vineyard Wind 1 to abide by vessel strike avoidance measures and a NMFS-approved marine mammal vessel strike avoidance plan, Vineyard Wind 1 is also required to equip all vessels with properly installed, operational Automatic Identification System (AIS) device and report all Maritime Mobile Service Identity (MMSI) numbers to NMFS. See Comment 12 for additional detail on expanding mitigation zones. The required mitigation and monitoring measures described in the Federal Register notice for the proposed IHA and this notice were designed based upon the best available science. In terms of a moratorium on east coast wind projects, it is beyond the scope of NMFS' authority to place a moratorium on these projects as NMFS only authorizes marine mammal take incidental to an activity (provided we make the necessary findings) and not the activity itself.

Comment 16: One commenter notes that the vessel speed restriction of traveling a maximum of 10 kn (11.5 mph) does not apply to crew transfer vessels. The commenter suggests that these restrictions should apply to crew transfer vessels as these vessels undertake the majority of project trips.

Response: NMFS agrees with the commenter that the vessel speed restriction of traveling a maximum of 10 kn (11.5 mph) should apply to all project vessels in a transit corridor if PAM is not used to monitor the transit corridor. NMFS included this measure in the Federal Register notice for the proposed IHA as well as the final IHA.

Comment 17: A commenter notes that the IHA should be more specific in defining the vessel transit corridor.

Response: NMFS appreciates the commenter's request to define the vessel transit corridor. The transit corridor is defined as the route a vessel takes from a port to the lease area and return. This definition is provided in the Vessel Strike Avoidance Measures section of this Federal Register notice as well as condition 5(b)(viii) of the IHA.

Monitoring, Reporting, and Adaptive Management

Comment 18: Multiple commenters claim that NMFS should require 100 percent on board agency enforcement coverage during the proposed Vineyard Wind 1 construction activities instead of allowing self-reporting and self-verification of acoustic impacts by Vineyard Wind 1, specifically regarding critically endangered species. The commenters further note that NMFS should require enforcement personnel on board project vessels or camera coverage of all offshore wind activity with camera footage that is reviewed by NOAA's Office of Law Enforcement (OLE). In order to verify that Vineyard Wind 1 adheres to all sound attenuation measures, a commenter further recommends that NMFS place an Office of Protected Resource “observer” on the vessel to confirm sound attenuation for each monopile. A commenter also suggests that NMFS hire a third-party safety officer to observe pile driving, confirm pile refusal or use of lower hammer energies, and create a safety plan for PSOs and PAM operators in the event of pile refusal.

Response: The IHA requires multiple mitigation and monitoring measures to effect the least practicable adverse impact on affected species or stocks of marine mammals, as well as extensive reporting requirements that document compliance and observed marine mammal responses to the activities by independent NMFS-approved PSOs. In terms of vessel strike avoidance measures, NMFS maintains an Enforcement Hotline for members of the public to report violations of vessel speed restrictions. While it is beyond the scope of 101(a)(5)(D) of the MMPA to include requirements of NMFS OLE personnel, the IHA includes two provisions related to the commenters recommendation: one states that by accepting the issued IHA, Vineyard Wind 1 consents to on-site observation and inspections by Federal agency personnel (including NOAA personnel) during activities this IHA covers, for the purposes of evaluating the implementation and effectiveness of measures contained within the IHA; the other states that 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 and indicates that personnel may report any violations to the NMFS Office of Law Enforcement.

NMFS is also not requiring additional observers to “confirm sound attenuation” for each monopile. As described in both the Federal Register notice for the proposed IHA and this notice, NMFS has included requirements for sound attenuation methods that were previously evaluated in SFV measurements conducted during Vineyard Wind 1 construction activities in 2023. Further, additional in situ SFV measurements will be conducted to ensure that sound levels are at or below those modeled (assuming 6 dB attenuation for Level A harassment) or those measured and expected (for Level B harassment) in 2023. In addition, Vineyard Wind 1 will be required to follow specific protocol when conducting SFV measurements, as described in conditions 5(a)(xvi-xxi) in the IHA, and report SFV measurements to NMFS Office of Protected Resources within 48 hours of each foundation installation as well as on a weekly, monthly, and annual basis. Frequent reporting will ensure that NMFS is aware of any threshold exceedances and the measures Vineyard Wind 1 would be implementing to ensure the Level A and Level B harassment isopleths do not exceed those modeled or expected for foundation installation.

Comment 19: One commenter expressed concern that NMFS should hold Vineyard Wind 1 accountable for maintaining sound levels during construction activities. The commenter further noted that submitting final SFV measurements within 90 days of completing SFV is not acceptable and removes accountability from Vineyard Wind1. The commenter suggested that NMFS should require Vineyard Wind 1 to complete the final results of SFV measurements within 48 hours of pile driving completion for each pile, instead of 90 days, and future piles should be dependent upon completion, review, and NMFS acceptance of daily SFV reports. Another commenter suggested that each monopile should be required to have its own SFV measurements registered throughout pile driving with a NMFS observer who can monitor and stop by pile driving, if necessary, until attenuation is achieved.

Response: NMFS agrees with the commenters that Vineyard Wind 1 should be held accountable for maintaining agrees with the commenters that Vineyard Wind 1 should be held accountable for maintaining the sound levels analyzed for the IHA during construction activities, though, as described above in Comment 18, while it is possible to measure the overall sound levels that include the NAS, there is no way to specifically confirm a 6-dB sound reduction as compared to an unattenuated pile. In situ measurements will continue to be conducted to verify sound levels are at or below those modeled or measured, as specified.

Although NMFS requires a SFV report to be submitted within 90 days of activity completion, NMFS also requires Vineyard Wind 1 to review SFV results within 24 hours and submit weekly, monthly, annual, and situational reports. As described in the Federal Register notice for the proposed IHA and this notice, Vineyard Wind 1 is required to provide the initial results of the SFV measurements to NMFS 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. In addition, each monopile must be acoustically monitored either using thorough SFV or abbreviated SFV. Again, it is not known if attenuation is achieved until results are reviewed within 24 hours, however, if SFV measurements exceed those distances that are modeled (Level A harassment) or measured (Level B harassment), Vineyard Wind 1 must notify NMFS and implement mitigative measures, as described in condition 5(a)(xxi) of the IHA.

Comment 20: A commenter claims that it is insufficient to visually and acoustically monitor for marine mammals for only 1 hour prior to beginning construction activities. Another commenter further indicates that NMFS should require two active PAM operators (instead of one) to increase situational awareness and active monitoring of hydrophones during the 60 minute pre-start clearance period.

Response: NMFS agrees with the commenter that monitoring more than one hour prior to beginning construction is appropriate. In addition to a 60 minute pre-start clearance period for visual observation and the requirement for PAM operator(s) to actively monitor hydrophones for 60 minutes prior to commencement of construction activities, both the proposed and final IHA include a requirement that Vineyard Wind 1 must also review PAM data collected for at least 24 hours in advance of pile driving activity to increase situational awareness of marine mammals in the area. Davis et al. (2023) found that by increasing pre-construction acoustic monitoring from 1 hour to 18 hours increased the likelihood of detecting a North Atlantic right whale from 4 percent to 74 percent.

At least one PAM operator is required to actively monitor and review PAM data from at least the past 24 hours to increase situational awareness. However, the number of active on-duty PAM operators must be sufficient to meet the requirements of the IHA. Vineyard Wind 1 is required to submit a PAM Plan for NMFS approval, which will specify the planned number of PAM operators that would be active to meet the IHA requirements.

Comment 21: Commenters claim that PSOs have poor detection capabilities and should not be relied upon for monitoring, most notably in low visibility conditions. A commenter cited the Williams et al. (2016) study, specifically noting that in the “worst visibility conditions” PSO detection probability was near zero at 1,000 m and did not exceed 50 percent until the distance is less than about 500 meters. The same commenter also indicated that the “overall efficacy of PSOs is approximately 9 percent in detection” and the “overall efficacy” of PAM “is approximately 25 percent.” A commenter further claims that PAM and low visibility equipment ( i.e., night vision goggles, infrared devices) proposed for monitoring are not effective and offer unreliable rates of detection, citing that PAM as a monitoring tool includes numerous limitations such as detecting marine mammals when they are not actively vocalizing and vocalizations of sufficient magnitude.

Response: NMFS disagrees that monitoring using a combination of PSOs and PAM will not be effective at detecting marine mammals. As described in the Federal Register notice for the proposed IHA, NMFS is requiring that Vineyard Wind 1 employ both visual and PAM methods for monitoring. Visual and PAM approaches 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). The use of PAM will augment visual detections for foundation pile driving, especially for activities with the largest zones. NMFS is requiring the use of PAM to monitor 10 km zones around the piles and that the systems be capable of detecting marine mammals during pile driving within this zone. For these reasons, NMFS finds that the suite of visual and acoustic monitoring measures in the Federal Register notice for the proposed IHA and carried forward in the IHA are based on the best available scientific information and are effective at detecting marine mammals.

We recognize that the distances at which marine mammals may be observed are both species and weather dependent. The commenter relies on Williams et al. (2016), in claiming that PSO detection probability was near zero at 1,000 m, however, this detection probability was based upon monitoring during poor visibility conditions. As visibility conditions improved during the study, PSO detection probability increased. Under this IHA, Vineyard Wind 1 is required to conduct monitoring in a manner such that PSOs can visually monitor an area no smaller than the minimum visibility zone (4,000 m; 13,123 ft). Pile driving may not occur in any conditions (including poor visibility conditions such as fog, rain, or darkness) if PSOs are not able to sight marine mammals in this minimum visibility zone out to this distance. During construction of Vineyard Wind 1 in 2023 and South Fork Wind, PSOs observed baleen whales at ranges as distant as 4 km (13, 123 ft) and 23 km (75,459 ft), respectively (RPS, 2024; South Fork Wind, 2024). The commenter did not provide evidence to support claims the minimum visibility zone could not be effectively monitored during good weather conditions, and NMFS disagrees with the commenters that, during good weather conditions, Vineyard Wind 1 would not be able to effectively monitor the minimum visibility zone.

NMFS recognizes that visual detection may not be 100 percent effective. Animals may be missed because they are underwater ( i.e., availability bias) or because they are available to be seen but are missed by observers ( i.e., perception and detection biases) ( e.g., Marsh and Sinclair, 1989). However, visual observation remains one of the best available methods for marine mammal detection.

The commenter indicates that PAM is limited to only detecting animals that are vocalizing, and vocalizations must be of “sufficient magnitude to surmount background noise” and be detected at the receiving station. NMFS acknowledges these limitations, however, there are a wide variety of PAM systems available on the market (van Parijs et al., 2021), ranging from omnidirectional independent acoustic buoys to multi-channel hydrophone arrays that are capable of detecting marine mammals in real-time. Real-time (or near real-time) stationary and mobile PAM systems are currently being used to inform management decisions and literature supports the effectiveness of real-time PAM at detecting marine mammals, including North Atlantic right whales (Ceballos et al., 2022; Murray et al., 2022; Baumgartner et al., 2020; Baumgarnter et al., 2019). In 2023, Vineyard Wind documented 253 acoustic detections of protected species during the project (with and in the absence of pile driving). Of the detections, 206 detections were unidentified dolphin, 45 detections of fin whales, and two detections of unidentified baleen whales (RPS, 2024). Vineyard Wind 1 is required to submit a PAM Plan to NMFS that demonstrates the system will be able to detect North Atlantic right whales at ranges up to 10 km (32,808.4 ft). To date, offshore wind developers have used bottom-mounted PAM systems located at distance from piles being installed. The final IHA requires the PAM system be placed no closer than 1 km (3,280.8 ft) from the pile being installed to minimize masking of North Atlantic right whale calls by construction noise.

Comment 22: A commenter indicates that all reports of endangered species should be logged and reported to NMFS within 24 hours.

Response: As described in the proposed IHA, Vineyard Wind 1 is required to report North Atlantic right whale sightings and acoustic detections to NMFS within 24 hours. As mentioned above in Comment 12 above, some mitigation, monitoring, and reporting measures are focused on North Atlantic right whales due to the species status and general fitness of individuals. It is not practicable or necessary to require Vineyard Wind 1 to report all sightings of endangered species to NMFS within 24 hours, unless a detection is of an injured, entangled, or dead marine mammal (see Reporting section of Monitoring and Reporting), and the commenter does not provide a rationale for the recommended change. However, all whale sightings must be reported to vessel captains and PSOs. In addition, NMFS is requiring all acoustic and visual detections of marine mammals to be submitted in weekly, monthly, and annual reports. NMFS disagrees that more frequent reporting of all ESA-listed marine mammal species is necessary and considers the required monitoring and reporting requirements in the IHA to be robust and appropriate.

Effects Assessment

Comment 23: Multiple commenters have expressed concern for impacts of offshore wind construction activities on marine mammal prey. One commenter expressed concern specifically regarding impacts to North Atlantic right whale prey, such as copepods, due to heat emanating from electric cables associated with offshore wind farm development. In addition, commenters express concern for operational impacts on North Atlantic right whale prey. One commenter indicates that based upon the size of the turbines, impacts to North Atlantic right whale prey could occur up to 60 miles outside of the Lease Area. Another commenter notes that the Federal Register notice for the proposed IHA also does not address potential operational impacts to water circulation patterns that produce zooplankton aggregations near Nantucket Shoals. The commenter claims that due to the overlap between a NOAA conservation buffer near Nantucket Shoals and the Project Area, NMFS should not issue the IHA to Vineyard Wind 1.

Response: In the Federal Register notice for the proposed IHA, NMFS considered the potential impacts of structures and operational noise on marine mammals and their habitat, including prey, based on the best available science (see the Potential Effects to Marine Mammal Habitat and Potential Effects from Offshore Wind Farm Operational Noise in the Federal Register notice for the proposed IHA). NMFS provides further analysis of the impacts of turbine operation on marine mammal habitat and prey in the Impact on Habitat and Prey section of the Negligible Impact Analysis and Determination section of this Federal Register notice as well as in the reinitiated Biological Opinion. The commenter did not provide scientific evidence that suggests the analysis within the Federal Register notice for the proposed IHA was unsupported. NMFS has fully evaluated the potential impacts of both issuing this IHA over the one-year effective period and the potential impacts from long-term operations via the Biological Opinion (BiOp). We refer the reader to the Potential Effects of the Specified Activities on Marine Mammals and Their Habitat section and the Negligible Impact Determination section in the proposed and final IHA notice for further details.

NMFS is evaluating the effects of authorizing the take of marine mammals incidental to pile driving 15 monopile foundations. Vineyard Wind operations commenced in 2023 and would be ongoing without installation of the remaining piles. BOEM is the agency responsible for approving construction and operations of offshore wind farms. Impacts to the environment for other project related activities such as sending power to shore through buried electric cables was analyzed in BOEM's Environmental Impact Study (EIS) for the Project and are outside the scope of the NMFS' MMPA decision.

Comment 24: Commenters claim that due to impacts to the North Atlantic right whales, the proposed IHA violates the Endangered Species Act (ESA) and reinitiation of consultation indicates that Vineyard Wind 1 was not compliant with the 2021 IHA. In addition, one commenter suggests that all reasons and information necessitating the reinitiation of the Vineyard Wind 1 Biological Opinion be made available for public comment including an extension to the public comment period.

Response: NMFS disagrees with commenters that the proposed IHA violates the ESA or that the reinitiation of the consultation indicates that Vineyard Wind was not compliant with the 2023 IHA. On May 23, 2024, NMFS Office of Protected Resources reinitiated its ESA section 7 consultation due to consideration of updated marine mammal density data which have become available since issuance of the 2023 IHA and analysis of SFV data collected by Vineyard Wind 1 during the 2023 construction campaign in the analysis for this IHA. NMFS also considered modified mitigation and monitoring measures in this analysis. NMFS Greater Atlantic Regional Fisheries Office (GARFO) completed its consultation on August 23, 2024 and concluded that the proposed actions were likely to adversely affect but were not likely to jeopardize the continued existence of the North Atlantic right whale, fin whale, sei whale, or sperm whale. The reasons and information necessitating the reinitiation of the Vineyard Wind 1 Biological Opinion are described in the Endangered Species Act section of this Federal Register notice. The Federal Register notice for the proposed IHA also described the request for reinitiation of consultation. NMFS did not deem extension of the public comment period for the proposed IHA necessary or appropriate.

Comment 25: Multiple commenters claim that NMFS did not evaluate the cumulative effects of all projects ( e.g., the offshore wind projects of other companies) on marine mammals. One commenter claims that NMFS should conduct a cumulative impact assessment of all offshore wind surveys and construction projects on marine mammals. Another commenter further notes that “dividing and segmenting the estimated take analysis for Vineyard Wind 1 across two years provides an inaccurate picture of total and cumulative effects” on North Atlantic right whales.

Response: NMFS is required to authorize the requested incidental take of small numbers of marine mammals of a species or stock by U.S. citizens if it finds the total take “while engaging in that (specified) activity” within a specified geographical region will have a negligible impact on such species or stock and, where applicable, will not have an unmitigable adverse impact on the availability of such species or stock for subsistence uses (16 U.S.C. 1371(a)(5)(A)). Negligible impact is defined 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 effect on annual rates of recruitment or survival” (50 CFR 216.103). Consistent with the preamble of NMFS' implementing regulations (54 FR 40338, September 29, 1989), the impacts from other past and ongoing anthropogenic activities are factored into the baseline, which is used in the negligible impact analysis. Here, NMFS has factored into its negligible impact analysis the impacts of other past and ongoing anthropogenic activities via their impacts on the baseline ( e.g., as reflected in the density/distribution and status of the species, population size and growth rate, and other relevant stressors).

The preamble of NMFS' implementing regulations also addresses cumulative effects from future, unrelated activities. Such effects are not considered in making the negligible impact determination under MMPA section 101(a)(5). NMFS considers: (1) cumulative effects that are reasonably foreseeable when preparing a National Environmental Policy Act (NEPA) analysis; and (2) reasonably foreseeable cumulative effects under section 7 of the ESA for ESA-listed species, as appropriate. Accordingly, NMFS has reviewed BOEM's 2021 EIS as part of its inter-agency coordination and determined that the analysis in the 2021 EIS for the Vineyard Wind 1 Offshore Wind Project is sufficient to cover the more limited scope of the remaining construction activities for this project. The EIS addresses cumulative impacts related to the Project and substantially similar activities in similar locations. Cumulative impacts regarding the issuance of an IHA for construction activities planned by Vineyard Wind 1 have been adequately addressed in the adopted EIS that supports NMFS' determination that this action has been appropriately analyzed under NEPA. Separately, the cumulative effects of the Project on ESA-listed species, including the North Atlantic right whale, were analyzed in NMFS' biological opinion issued under section 7 of the ESA following formal inter-agency consultation with the NOAA Greater Atlantic Regional Field Office (GARFO). Following reinitiated consultation on May 23, 2024, GARFO issued a new BiOp that determined that NMFS' issuance of an IHA for construction activities, individually and cumulatively, are likely to adversely affect, but not jeopardize, listed marine mammals.

NMFS disagrees that dividing estimated take analysis for Vineyard Wind 1 across two years provides an inaccurate picture of cumulative effects on North Atlantic right whales. The take authorized in this IHA represents a subset of the take authorized under the 2023 IHA and is based upon the reduced scope of work remaining for the project. As NMFS has determined the 2021 EIS remains appropriate for this analysis, cumulative effects on marine mammal species, including North Atlantic right whales, are taken into account.

Comment 26: Citing to new data in Finneran et al. (2023), commenters raise questions about the validity of NMFS' current noise exposure guidelines for dolphins at frequencies below ~1kHz and how to accurately estimate received noise levels from free-swimming animals, Commenters recommend NMFS conduct a new analysis and enlarge the exclusion and clearance zones for marine mammals, particularly bottlenose dolphins and long finned pilot whales. Commenters also criticize specific facets of the methodology in NMFS 2018 Revised Technical Guidance, suggest the need for additional research, and suggested ongoing construction at Vineyard Wind cease or the IHA be withdrawn until NMFS updated its PTS/TTS thresholds for mid-frequency cetaceans.

Response: NMFS disagrees that the analysis or mitigation zones for marine mammals (and MF species specifically) require adjustments and that the IHA process be paused (or withdrawn) until more information is known on whether animals will move out of the area or NMFS finalizes updates to the 2018 Technical Guidance. Under section 101(a)(5)(D) of the MMPA, NMFS is required to issue the IHA if the taking will be for small numbers of the affected species or stocks and if NMFS is able to make the statutorily required negligible impact finding. Among other things, the IHA must prescribe the means of effecting the least practicable adverse impact on the affected species or stocks and their habitat. All of these standards are based on the best available information.

Our analyses for predicting auditory impacts on marine mammals are based primarily on our 2018 Technical Guidance for Assessing the Impacts of Anthropogenic Sound on Marine Mammal Hearing (NMFS, 2018). NMFS is currently in the process of updating that Technical Guidance, following a rigorous process involving external peer review, Federal agency review, and public comment (89 FR 36762, May 3, 2024). As the commenter notes, Finneran et al. (2023) suggests that high-frequency cetaceans (formerly classified as mid-frequency cetaceans in our 2018 Revised Technical Guidance) are more susceptible to noise-induced hearing loss below 1 kHz that previously thought, which will likely result in a change in the Technical Guidance. However, given the rigorous review process to update the Technical Guidance is not complete, the future updates are not quantitatively applied to this project. We note, however, potential anticipated changes to the Technical Guidance would not be expected to change the findings that support the issuance of this IHA.

Regarding some of the specific methodological concerns raised by commenters, NMFS disagrees that the use of means and medians is inappropriate or that the methodology should be compared to that used in the calculation of potential biological removal (PBR). The Technical Guidance's methodology is designed to predict the mostly likely (realistic) outcome using the central tendencies (means/median) associated with the best available science. The intent is not to predict the worst-case-scenario by relying on the lowest limits for every possible step in the methodology ( i.e., Technical Guidance is for accurately predicting exposures and not for establishing “safe limits,” where there is limited to no risk). Further, within the development of the criteria, several assumptions were made to address uncertainty, including the amount of threshold shift defining TTS onset ( e.g,. 6 dB threshold shift, which is the minimum threshold shift clearly larger than any day-to-day or session-to-session variation) and PTS onset (40 dB shift, where there have been no reports of PTS in a marine mammal whose initial behavioral threshold shift was 40 dB or less) and that there is no recovery between intermittent exposures. Regarding the observation that the data upon which the Technical Guidance is based are limited in some ways, we do not disagree, but are nonetheless charged with basing our analyses on the best available information and have described a reasonable methodology that does so.

Contrary to the commenters' assertions, NMFS has not drawn any conclusions about TTS based on PSO observations and a commenter incorrectly implies that the clearance and shutdown zones in the proposed IHA, including the 160-m zone for dolphins, are intended to avoid TTS. As described in the Federal Register notice for the proposed IHA, NMFS does not quantitatively distinguish Level B harassment in the form of direct behavioral disturbance from a disruption of behavioral patterns resulting indirectly from TTS, but, rather, notes that the predicted takes by Level B harassment could include either. Moreover, the distances at which TTS onset is likely are smaller relative to those where behavioral disruption without any TTS is expected. Regarding the comment related to auditory brainstem response (ABR), NMFS disagrees that conclusions in Finneran et al. 2023 cast doubt on the NMFS TTS threshold methodology generally for all species. The results of Finneran et al. 2023 show that hearing and TTS data, relying on behavioral methodology, cannot be directly compared to measurements using ABR methods. Finneran et al. 2023 indicate “Correlation between TTS measured behaviorally and with ABRs was weak (figure 13) and ABR-measured TTS was typically lower and more variable than that measured behaviorally for the same exposure” and later that “In practice, however, ABR measurements in the present study provided only limited value.” While we acknowledge the differences in these two methods in predicting TTS onset, especially at lower frequencies, the information does not support the commenters assertion that NMFS analysis needs to change or that mitigation zones must be enlarged, since, as noted above, the analysis already acknowledges that the potential for TTS in the quantified takes by Level B harassment and the mitigation zones are intended to avoid or minimize PTS, not TTS. Finally, the relationship between ABR and behavioral hearing measurements is not relevant to PSO observations of behavior.

Finally, regarding our mitigation under the applicable least practicable adverse impact standard, our proposed IHA notice explains clearance and shutdown zones are intended to avoid or minimize the likelihood of Level A harassment and reduce the severity or likelihood of Level B harassment. Importantly, the size of the clearance and shutdown zones for all marine mammals s larger than the modeled Level A harassment (PTS) distances which, based on SFV data from the 2023 pile driving season, is an overestimate. Specifically for mid frequency cetaceans, the estimated distance to PTS is 43 m; however, the clearance and shutdown zone is set at 160 m due to presence of the bubble curtain. For the North Atlantic right whale, the distance to the clearance and shutdown zone is independent of both PTS and TTS in that they are any distance by PSOs or within 10 km if acoustically detected.

Comment 27: Multiple commenters urged NMFS to deny the proposed project and/or postpone any offshore wind activities until NMFS determines effects of all offshore wind activities on marine mammals in the region and determines that the recent whale deaths are not related to OSW activities. Similarly, some commenters provided general concerns regarding recent whale stranding events on the Atlantic Coast, including speculation that the strandings may be related to wind energy development-related activities. A commenter further states that offshore wind construction activities have been linked to marine mammal injury and deafness.

Response: While NMFS acknowledges that offshore wind development activities, including HRG survey effort, have increased in the Atlantic Ocean during the time period of increased whale strandings, there is no scientific evidence that these development activities, such as HRG survey effort and turbine construction, are contributing factors to the strandings. Further, HRG surveys are not part of the specified activity. NMFS does not agree that mortality is an anticipated outcome of these specified activities, and there is no evidence to suggest otherwise, as described below. Further, the proposed IHA (89 FR 31008, April 23, 2024) clearly states that no serious injury and/or mortality was requested by Vineyard Wind 1, is expected, or was proposed to be authorized.

The best available science indicates that the anticipated impacts from pile driving of turbines potentially include temporary avoidance of localized areas, cessation of foraging or communication, TTS, stress, masking, etc., (as described in the Effects of the Specified Activities on Marine Mammals and their Habitat section in the Federal Register notice for the proposed IHA). NMFS emphasizes that there is no evidence that noise resulting from offshore wind development would cause marine mammal strandings, and there is no evidence linking recent large whale mortalities and currently ongoing offshore wind activities ( e.g., HRG surveys or construction). The commenters offer no such evidence or other scientific information to substantiate their claim. This point has been well supported by other agencies, including the Marine Mammal Commission (Marine Mammal Commission Newsletter, Spring 2023). Additionally, a recent paper by Thorne and Wiley (2024) reviewed spatiotemporal patterns of strandings, mortalities, and serious injuries of humpback whales along the U.S. East Coast from 2016-2022. Humpback whales were chosen as a case study for this analysis as they are currently undergoing a UME and strand more often than other large whale species. Thorne and Wiley (2024) found vessel strikes to be a major driver in the increase of humpback whale strandings, mortalities, and serious injury along the east coast. The potential for vessel strike increased during the study period due to increased vessel traffic in new foraging areas, the increased presence of juvenile humpback whales, and humpback whale foraging in shallow areas that overlap with vessel traffic. Based upon the spatiotemporal analysis, no evidence was found that offshore wind development played a role in the increased number of strandings over time. Future studies should focus on gaining a greater understanding of spatial and seasonal habitat use patterns of large whales, spatiotemporal changes in prey abundance and distribution, and how habitat use and foraging behavior affect the risk of vessel strike. While several species of delphinids and beaked whales have also stranded off New Jersey since 2011 (per data provided from the National Marine Stranding Network), there is no evidence that the acoustic sources used during HRG surveys contributed to these events. NMFS will continue to gather data to help us determine the cause of death for these stranded whales.

Recently, NMFS was made aware of a media article wherein a member of the public conducted a statistical analysis on the correlation between offshore wind vessel use and whale deaths along the U.S. east coast (Climate Change Dispatch, 2024). The parameters considered in the analysis were limited to offshore wind vessel movement and whale deaths. NMFS has long recognized that marine mammals strandings have increased over the years, including increases in strandings of three large whale species resulting in the declaration of Unusual Mortality Events for minke, humpback, and North Atlantic right whales in 2018, 2017, and 2017 respectively. Offshore wind development has increased over the same time period, so the correlation was not surprising. However, the analysis presented in the article was not peer-reviewed, was limited, not fully described, does not appear to separate out vessel movement from survey activities, did not consider other known factors that are increasing ship strike risk in general ( e.g., Thorne and Wiley, 2024) or other factors leading to increased strandings ( e.g., entanglement, climate change), and did not demonstrate that offshore wind vessel traffic or HRG surveys are the cause of strandings. Overall, while NMFS considered this information, it did not provide new information that links whale strandings to offshore wind vessel movement or surveys.

There is an ongoing UME for humpback whales along the Atlantic coast from Maine to Florida, which includes animals stranded since 2016, and we provide further information on the humpback whale and North Atlantic right whale UMEs in the Description of Marine Mammals in the Area of Specified Activities section of this notice. For humpback whales, partial or full necropsy examinations were conducted on approximately half of the whales that were recently stranded along the U.S. East Coast. Necropsies were not conducted on other carcasses because they were too decomposed, not brought to land, or stranded on protected lands ( e.g., national and state parks) with limited or no access. Of the whales examined (roughly 90), about 40 percent had evidence of human interaction, either ship strike or entanglement. Vessel strikes and entanglement in fishing gear are the greatest human threats to large whales. The remaining 50 necropsied whales either had an undetermined cause of death (due to a limited examination or decomposition of the carcass) or had other causes of death including parasite-caused organ damage and starvation. For North Atlantic right whales, starting in 2017, evaluated mortalities were documented in both Canada and the United States, with the whales documented for this UME as being dead, injured, and/or sick to the extent that more than 20 percent of the population has been affected. The preliminary cause of mortality, serious injury, and morbidity (sublethal injury and illness) in most of these whales is from entanglements or vessel strikes and human impacts continue to threaten the survival of this species. See NMFS' websites ( https://www.fisheries.noaa.gov/national/marine-life-distress/2016-2024-humpback-whale-unusual-mortality-event-along-atlantic-coast and https://www.fisheries.noaa.gov/national/marine-life-distress/2017-2024-north-atlantic-right-whale-unusual-mortality-event ) for more information on the ongoing humpback whale and North Atlantic right whale UMEs. More information about interactions between offshore wind energy projects and whales can be found at https://www.fisheries.noaa.gov/new-england-mid-atlantic/marine-life-distress/frequent-questions-offshore-wind-and-whales.

Comment 28: A commenter indicates that NMFS has not taken new information into account for the presence and behaviors of sperm whales in the proposed Project Area. The commenter further notes that due to high sperm whale presence in the Project Area, as described by Farmer et al. (2018) and Westell et al. (2024), NMFS should strengthen mitigation measures for sperm whales.

Response: NMFS disagrees that new information to account for the presence and behaviors of sperms whales in the Project Area have not been taken into account. Although Westell et al. (2024) acoustically identified sperm whale presence in the lease area during June and July 2020-2021, Vineyard Wind 1 PSO data collected during the 2023 construction campaign during June through December 2023 did not document any sightings of sperm whales in the Lease Area (RPS, 2024). In addition, there is no designated critical habitat or biologically important areas (BIAs) for this species in the vicinity of the LIA. The commenter also references the Farmer et al. (2018) study of disturbances to sperm whales, however, that study discusses the Gulf of Mexico stock of sperm whales specifically in the Gulf of Mexico. NMFS has included a robust suite of mitigation measures specific to sperm whales in the IHA, including a 500 m visual pre-start clearance zone, 500 m visual shutdown zone, a 500 m PAM clearance zone, and a 500 m PAM monitoring zone in addition to general mitigation measures regarding soft start, noise attenuation, and seasonal and daily pile driving restrictions. Due to limited documented occurrence during Vineyard Wind 1 activities in the lease area, NMFS does not agree that it is appropriate or warranted to extend mitigation measures for sperm whales.

Comment 29: One commenter claims that the NEPA process for the Vineyard Wind 1 IHA is segmented and that a cumulative EIS should be developed for the RI-MA WEA. The commenter further indicates that a cumulative EIS should include nine lease areas, including the proposed Vineyard Wind 1 Project Area within the WEA.

Response: NMFS' proposed action to issue an IHA to Vineyard Wind constitutes a major Federal action under NEPA. In 2021, after independent review, with specific attention given to its evaluation of effects to marine mammals and their habitat, NMFS adopted BOEM's Vineyard Wind 1 Final Environmental Impact Study (FEIS) to satisfy NMFS' independent NEPA obligations related to its decision under the MMPA of whether or not to issue an IHA to the Vineyard Wind and signed a Record of Decision on May 10, 2021. The FEIS evaluated the direct and indirect impacts of the project as well as the cumulative impacts of all past, present and foreseeable future actions, including full offshore wind build-out of the OCS. Therefore, the cumulative impacts from constructing wind farms in all proposed lease areas, including those in southern New England, is included in the FEIS. BOEM's Vineyard Wind 1 FEIS was challenged and upheld by a court. For these reasons, NMFS disagrees that a separate EIS that considers the nine lease areas in the RI-MA WEA alone is necessary to comply with NEPA for issuance of the IHA.

Comment 30: Commenters suggest that supplemental NEPA is necessary for the proposed action and the Vineyard Wind 1 EIS should be reopened to incorporate this analysis. One commenter recommends that the Vineyard Wind 1 Record of Decision (ROD) and project construction be suspended until a new FEIS is completed. Another commenter claims that the Vineyard Wind 1 ROD is in violation of NEPA as it was completed and approved before the reinitiated Biological Opinion in 2021 and also supported halting construction of the project. An additional commenter claims that supplemental NEPA would be necessary if any larger piles or a greater number (than 15) pile were to be installed and this NEPA should consider any changes to hammer type, hammer size, effects to the substrate, and effects on marine mammals.

Response: NMFS disagrees with commenters that a supplemental NEPA document is necessary for this action or that the FEIS is deficient. The planned completion of pile installation, including reduced scope of work, inclusion of in situ SFV data into the analysis, additional mitigation, monitoring, and reporting measures, and updated marine mammal density data, have been reviewed by NMFS to determine if supplementation is warranted. Vineyard Wind 1 has proposed to install the same size of the remaining 15 piles using the same hammer type. Supplementation of the Vineyard Wind 1 EIS is not required because this proposed action does not represent a substantial change to the Project and the proposed changes do not change the impact determinations. Therefore, the changes referenced here do not present significant new circumstances or information relevant to environmental concerns pertaining to the proposed action or its impacts (see 40 CFR 1502.9(d)(1)). NMFS has determined that the Vineyard Wind 1 FEIS is sufficient and a supplemental NEPA document is not necessary.

As the Vineyard Wind 1 FEIS is sufficient for the proposed action and a new FEIS does not need to be prepared, it is not necessary to suspend the ROD or project construction. In addition, the original Biological Opinion was finalized on September 11, 2020, in advance of the Vineyard Wind 1 ROD, finalized on May 10, 2021.

Changes From the Proposed IHA to the Final IHA

The text of several measures in the draft IHA was revised to improve the clarity and consistency of the measures. In addition, reporting requirements on marine mammals have been updated in accordance with Greater Atlantic Regional Fisheries Office (GARFO), Southeast Regional Office (SERO), and the Northeast Fisheries Science Center (NEFSC) most recent guidance. Several other measures were changes from the proposed IHA to the final IHA in consideration of public comments or other information. Changes are summarized here, with additional explanation provided later in the notice, as necessary:

• The requirement for NMFS approval for pile driving in December was removed as a mitigation requirement from the IHA. After the 30-day public comment period on the proposed IHA, Vineyard Wind 1 notified NMFS that pile driving would likely commence in November and continue into December. Therefore, NMFS removed the requirement for Vineyard Wind 1 to obtain prior approval from NMFS to pile drive in December;
• Pilot whales and Risso's dolphins were moved from the 500 m clearance and shutdown zone category to the 160 m clearance and shutdown zone category in the IHA. The distance to the Level A harassment zone for other mid-frequency cetaceans is 43 m, and a 160 m clearance and shutdown zone is sufficient to encompass this zone. In addition, the clearance and shutdown distance for other mid-frequency delphinids is 160 m. This change was also made to align with the Vineyard Wind 1 original request in the application;
• The timeframe for the use of vessel-based surveys to confirm the clearance zone is clear of North Atlantic right whales prior to pile driving has been extended from the original period of December 1-December 31, described in the proposed IHA notice to the period of November 1-December 31. This change was made to align with the Vineyard Wind 1 original request in the application and to provide increased mitigation during the month of November as well when North Atlantic right whale density begins to increase in the Project area;
• In response to a public comment, NMFS has added a measure to require Vineyard Wind 1 to cease pile driving if there is a live cetacean stranding within 50 km of pile driving activities and the NMFS Marine Mammal Stranding Network is attempting to herd or return animals to the water;
• The IHA measure describing the procedures for Vineyard Wind 1 to implement if any of the SFV measurements exceed the distance expected or modeled to any isopleth of concern was revised in the final IHA for clarity. The examples for a pile being installed with a single bubble curtain and near field sound attenuation device and the example for a double bubble curtain without a near field sound attenuation device were removed as Vineyard Wind 1 would be required to use both a double bubble curtain and near field sound attenuation device. In addition, the requirement for Vineyard Wind 1 to request concurrence from NMFS to proceed with pile driving after providing a written explanation of isopleth exceedance was removed. If any isopleth of concern is exceeded, Vineyard Wind 1 would be required to provide written explanation to NMFS Office of Protected Resources supporting their determination that adjustments to mitigation measures would be sufficient in reducing pile driving noise below the isopleth of concern and implement those measures;
• NMFS updated the SFV requirements in the IHA to align with the Biological Opinion Terms and Conditions;
• The educational requirement for PSOs and PAM operators to receive a bachelor's degree “from an accredited college or university” have been removed, although PSOs and PAM operators are still required to hold a bachelor's degree; and
• The requirement for full PAM detection data to be submitted with monthly reports has been updated due to a change in Northeast Fisheries Science Center reporting requirements. Vineyard Wind 1 must submit full PAM detection data within 90 days after foundation installation ceases and every 90 calendar days for transit lane PAM.

In addition, the following measure was added to the IHA section 5(a) to describe Vineyard Wind 1's obligation if SFV measurements show exceedance of expected Level A harassment or Level B harassment thresholds, including while implementing additional mitigation measures:

• If, after all practicable measures that could be taken to reduce noise levels have been successfully implemented and exhausted, Thorough SFV measurements continue to indicate that the distances to marine mammal Level A harassment thresholds are greater than those modeled assuming 6 dB attenuation and the Level B harassment thresholds based on SFV during the 2023 campaign, Vineyard Wind 1 must meet with NMFS within 3 three business days to discuss: the results of SFV monitoring, the severity of exceedance of distances to identified isopleths of concern, the species affected, modeling assumptions, and whether the SFV results demonstrate the magnitude and degree of impacts from the Project are greater than those considered in this final IHA.

Description of Marine Mammals in the Area of Specified Activities

Thirty-eight marine mammal species, comprising 39 stocks, under NMFS' jurisdiction have geographic ranges overlapping the western North Atlantic OCS (Hayes et al., 2023). However, for reasons described below, Vineyard Wind 1 has requested, and NMFS has authorized, take of only 14 species (comprising 14 stocks) of marine mammals. Sections 3 and 4 of the 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, instead of reprinting the information. See ADDRESSES . Additional information regarding population trends and threats may be found in NMFS' Stock Assessment Reports (SARs; www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessments ) 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 ).

Table 1 lists all species or stocks for which take is expected and authorized for this activity and summarizes information related to the population or stock, including regulatory status under the MMPA and ESA and PBR, where known. PBR is defined by the MMPA 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 (as described in NMFS' SARs; 16 U.S.C. 1362(20)). While no serious injury or mortality is anticipated or 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. Four of the marine mammal species for which take is authorized are listed as endangered under the ESA, including the North Atlantic right whale, fin whale, sei whale, and sperm whale.

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 comprise 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. 2023 draft SARs and NMFS' U.S. 2022 SARs. 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 specific geographic region. All values presented in table 1 are the most recent available at the time of publication and are available online at: www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessments.