# Takes of Marine Mammals Incidental to Specified Activities; U.S. Navy Training Activities in the Gulf of Alaska Temporary Maritime Activities Area > Briefs, arguments, decisions, and more. URL: https://www.frixlaw.com/law-library/documents/fr%3A2017-08424 ## Record - **Collection:** Federal Register - **Document type:** Rule - **Published:** April 27, 2017 - **Citation:** 82 FR 19530 ## Text DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration 50 CFR Part 218 [Docket No. 141125997-7365-02] RIN 0648-BE67 Takes of Marine Mammals Incidental to Specified Activities; U.S. Navy Training Activities in the Gulf of Alaska Temporary Maritime Activities Area AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and Atmospheric Administration (NOAA), Commerce. ACTION: Final rule. SUMMARY: Upon application from the U.S. Navy (Navy), we (NMFS) are issuing regulations under the Marine Mammal Protection Act (MMPA) to govern the unintentional taking of marine mammals incidental to the training activities conducted in the Gulf of Alaska (GOA) Temporary Maritime Activities Area (TMAA) Study Area (hereafter referred to the Study Area) from May 2017 through May 2022. These regulations allow us to issue a Letter of Authorization (LOA) for the incidental take of marine mammals during the Navy's specified activities and timeframes, set forth the permissible methods of taking, set forth other means of effecting the least practicable adverse impact on marine mammal species or stocks and their habitat, and set forth requirements pertaining to the monitoring and reporting of the incidental take. DATES: Effective April 26, 2017, through April 26, 2022. ADDRESSES: To obtain an electronic copy of the Navy's LOA application or other referenced documents, visit the internet at: http://www.nmfs.noaa.gov/pr/permits/incidental/military.htm. Documents cited in this notice may also be viewed, by appointment, during regular business hours, at 1315 East-West Highway, SSMC III, Silver Spring, MD 20912. FOR FURTHER INFORMATION CONTACT: Jolie Harrison, Office of Protected Resources, NMFS, (301) 427-8477. SUPPLEMENTARY INFORMATION: Availability A copy of the Navy's LOA application may be obtained by visiting the internet at: http://www.nmfs.noaa.gov/pr/permits/incidental/military.htm. The Navy's Final Supplemental Environmental Impact Statement/Overseas Environmental Impact Statement (FSEIS/OEIS) for the GOA TMAA Study Area, which also contains a list of the references used in this document, may be viewed at http://www.goaeis.com. Documents cited in this notice may also be viewed, by appointment, during regular business hours, at the aforementioned address (see ADDRESSES ). Background Sections 101(a)(5)(A) and (D) of the MMPA (16 U.S.C. 1361 et seq. ) direct the Secretary of Commerce 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 regulations are issued or, if the taking is limited to harassment, a notice of a proposed authorization 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), will not have an unmitigable adverse impact on the availability of the species or stock(s) for subsistence uses (where relevant), and if the Secretary sets forth permissible methods of taking and other means of effecting the least practicable impact on the species or stock and its habitat. NMFS has defined “negligible impact” in 50 CFR 216.103 as “an impact resulting from the specified activity that cannot be reasonably expected to, and is not reasonably likely to, adversely affect the species or stock through effects on annual rates of recruitment or survival.” The National Defense Authorization Act of 2004 (NDAA) (Pub. L. 108-136) removed the “small numbers” and “specified geographical region” limitations indicated above and amended the definition of “harassment” as applies to a “military readiness activity” to read as follows (section 3(18)(B) of the MMPA, 16 U.S.C. 1362(18)(B)): “(i) Any act that injures or has the significant potential to injure a marine mammal or marine mammal stock in the wild” (Level A Harassment); or “(ii) Any act that disturbs or is likely to disturb a marine mammal or marine mammal stock in the wild by causing disruption of natural behavioral patterns, including, but not limited to, migration, surfacing, nursing, breeding, feeding, or sheltering, to a point where such behavioral patterns are abandoned or significantly altered” (Level B Harassment). Summary of Request On July 28, 2014, NMFS received an application from the Navy requesting an LOA for the take of 19 species of marine mammals, representing 27 stocks, incidental to Navy training activities to be conducted in the Study Area over 5 years. On October 14, 2014, the Navy submitted a revised LOA application to reflect minor changes in the number and types of training activities. To address minor inconsistencies with the draft SEIS/OEIS (DSEIS/OEIS), the Navy submitted a final revision to the LOA application (hereafter referred to as the LOA application) on January 21, 2015. In November 2016, the Navy requested that the final rule and LOA be issued for the training activities addressed by Alternative 1 of the FSEIS/OEIS. The Navy's LOA application was based on the training activities addressed by Alternative 2 of the DSEIS/OEIS; therefore, our proposed rule (81 FR 9950; February 26, 2016) analyzed the level of activities as described by Alternative 2. Pursuant to the Navy's November 2016 request, the final rule now reflects the training activities addressed by Alternative 1 of the FSEIS/OEIS, which include a subset of the activities analyzed in the proposed rule. The change from Alternative 2 to Alternative 1 results in a significant reduction in proposed training activities (see “Training” and “Summary of Impulsive and Non-Impulsive Sources”), lessening the number of the Carrier Strike Group Events from 2 to 1 per year, and the number of SINKEXs from 2 to 0 per year, which means that several types of explosives will no longer be used and there will be no live MISSILEX. This significantly decreases the number of anticipated and authorized takes for this activity (see “Take Request”) compared to what was presented in the proposed rule. The Navy is requesting a five-year LOA for training activities to be conducted from May 2017 through May 2022. The Study Area is a polygon roughly the shape of a 300 nm by 150 nm rectangle oriented northwest to southeast in the long direction, located south of Prince William Sound and east of Kodiak Island, Alaska (see Figure 1-1 of the LOA application for a map of the Study Area). The activities conducted within the Study Area are classified as military readiness activities. The Navy states that these activities may expose some of the marine mammals present within the Study Area to sound from underwater acoustic sources and explosives. The Navy's request for authorization is for the incidental take of individuals of 19 species of marine mammals, representing 27 stocks, by Level B harassment and one species of marine mammal (Dall's porpoise) by Level A harassment. The Navy is not requesting mortality takes for any species. The LOA application, proposed rule (81 FR 9950; February 26, 2016), and GOA FSEIS/OEIS contain acoustic thresholds that, in some instances, represent changes from what NMFS has used to evaluate the Navy's activities for previous authorizations. These thresholds, which the Navy developed in coordination with NMFS, are based on the evaluation and inclusion of new information from recent scientific studies; a detailed explanation of how they were derived is provided in the GOA FSEIS/OEIS Criteria and Thresholds for U.S. Navy Acoustic and Explosive Effects Analysis Technical Report (available at http://www.goaeis.com ). On August 4, 2016, NMFS released its Technical Guidance for Assessing the Effects of Anthropogenic Sound on Marine Mammal Hearing (new Guidance). This new Guidance established new thresholds and associated weighting functions for predicting auditory injury, or permanent threshold shift (PTS), which equates to Level A harassment under the MMPA, and temporary threshold shift (TTS), which is considered Level B harassment under the MMPA. In the August 4, 2016, Federal Register notice announcing the new Guidance (81 FR 51694), NMFS explained the approach it would take during a transition period, during which we will balance the need to consider this new best available science with the fact that some applicants have already committed time and resources to the development of analyses based on our previous thresholds and have constraints that preclude the recalculation of take estimates, as well as consideration of where the action is in the agency's decision-making “pipeline.” In that notice, we included a non-exhaustive list of factors that would inform the most appropriate approach for considering the new Guidance, including: How far in the process the application or prospective application has progressed; when the activity is scheduled to begin or other timing constraints; the complexity of the analyses and the cost and practicality of redoing them; the temporal and spatial scope of anticipated effects; and the relative degree to which the new Guidance is expected to affect the results of the acoustic impact analyses. In developing the new Guidance, NMFS compiled, interpreted, and synthesized scientific information currently available on the effects of anthropogenic sound on marine mammals, including a recent Technical Report by Dr. James Finneran (U.S. Navy-SPAWAR Systems Center Pacific) that proposed new weighting functions and thresholds for predicting the onset of both PTS and temporary threshold shifts (TTS) in marine mammals (Finneran, 2016). The methodologies presented within this paper (and in NMFS' new Guidance) build upon the methodologies used to develop the criteria applied within the proposed rule and Navy's GOA FSEIS/OEIS (Finneran and Jenkins, 2012), and incorporate relevant auditory research made available since 2012 ( e.g., Kastelein et al., 2012a; Kastelein et al., 2012b; Finneran and Schlundt, 2013; Kastelein et al., 2013a; Kastelein et al., 2013b; Popov et al., 2013; Kastelein et al., 2014a; Kastelein et al., 2014b; Popov et al., 2014; Finneran et al., 2015; Kastelein et al., 2015a; Kastelein et al., 2015b; Popov et al., 2015). In light of limited data at the time, Finneran and Jenkins (2012) presented a conservative approach to development of auditory weighting functions. In 2016, with the benefit of newly-available data, Finneran was able to synthesize a wide range of auditory data, including newly-available studies, to predict refined auditory weighting functions and corresponding TTS and PTS thresholds across the complete hearing ranges of functional hearing groups. At the time of the release of the proposed rule and GOA FSEIS/OEIS, NMFS' new Guidance had not been issued. Further, the new criteria were not available for the Navy's acoustic effects modeling used to calculate distances to harassment thresholds and resulting take estimates. Therefore, the Navy did not directly use the new auditory weighting functions and PTS/TTS criteria in its GOA FSEIS/OEIS. In addition to the fact that it was possible to address the new Guidance adequately without remodeling it would have been impractical for the Navy to entirely re-model its proposed action based on the new Guidance. The Navy committed substantial time and resources to the development of acoustic analyses based on previous acoustic thresholds. Data and information ( e.g., on marine species density) gathering for this second GOA rule (Phase II, 2017-2022) modeling began in November 2011 and subsequent modeling occurred over a 20-month period from October 2012 to June 2014. The contract costs for modeling GOA events were significant, as was Navy Pacific Fleet staff labor. The underlying science contained within Finneran (2016) (upon which NMFS' new Guidance is based) has been addressed qualitatively within the applicable sections of the GOA FSEIS/OEIS and this final rulemaking. Further, although the writers of the base code for the model used for Phase II were not available to recode the model with the updated impulsive criteria in terms of weighting functions, the Navy was able to use the model to reprocess anticipated explosive ranges to effects for PTS based on the criteria presented in the new Guidance to assess if the new criteria could result in any additional species-specific injury exposures. In short, the Navy quantitatively reanalyzed PTS ranges and exposures from explosive sources using the new Guidance, from which TTS and behavioral exposures could be estimated, but the sonar exposures were not remodeled because a qualitative assessment of the new Guidance and the activities showed that it was not necessary in order to support the analysis, in addition to being impractical. For the sonar exposure estimates, if the new Guidance was quantitatively applied to the GOA TMAA effects analysis and new modeling conducted, predicted numbers of PTS and/or TTS would change to some small degree (even if only by fractions of a take). However, because the new Guidance relies on much of the same data as the auditory criteria presented in the proposed rule and the Navy's GOA FSEIS/OEIS, these changes would not be substantial (as described in more detail below), and in most cases would result in a reduction in the predicted impacts. Onset PTS thresholds for non-impulsive sound (sonar) are largely lower ( i.e., are more conservative) in Finneran and Jenkins 2012 (used in GOA FSEIS/OEIS) compared to the new Guidance, while updated auditory weighting functions for most marine mammal hearing groups have changed minimally in the new Guidance. This means that the predicted ranges to PTS and TTS in the GOA FSEIS/OEIS and this final rule for non-impulsive sources would change only minimally (and for the most part are larger than what would result) if NMFS' new Guidance were quantitatively applied and new modeling conducted ( i.e., estimated numbers of takes resulting in PTS and TTS from sonar are, for the most part, larger in this final rule than would be expected if the Navy's activities were re-modeled using the new Guidance). Specifically, PTS thresholds for non-impulsive sources for all taxa went up ( i.e., are less conservative), except for Otariids, for which they went down by one dB. Given that the PTS range to effects for Otariids was previously 10m, a 1 dB change in the PTS threshold would not change the PTS range to effects by more than a couple of meters for any acoustic source. For TTS, the onset thresholds for cetaceans in the new Guidance all went up ( i.e., are less conservative) or stayed the same ( i.e., ranges to effects and take estimates for TTS would go down or stay the same for cetaceans if the Navy's activities were re-modeled using the new Guidance). The onset thresholds for TTS for Phocids and Otariids went down by 2 dB and 7 dB, respectively. The previous range to effects was 70-1720m for Phocids and 230-570m for Otariids for the largest source (53C). If spherical spreading were conservatively considered, applying the new Guidance, the range to TTS for Phocids would likely be no more than approximately 100-2,200m and the range for Otariids would likely be no more than approximately 500-1,300m. The originally modeled TTS for pinnipeds was zero for all but one species. When the lower likelihood of overlap of most pinniped species (those with 0 TTS estimates) with these activities is considered in combination with their densities and the change in the size of the ensonified zone, our analysis still suggests that TTS take is not likely to occur, and those Level B take estimates have not been changed. Further, any small changes to predicted TTS takes for Northern elephant seals that might result from applying the new guidance, and specifically considering the slightly larger ensonified volume resulting from the 2 dB decrease in the threshold, would be expected to be in the form of changing a modeled behavioral harassment to a TTS, resulting in no net change in the Level B harassment take estimates. For impulsive sound (explosives), the Navy was able to reprocess anticipated ranges to effects for Level A harassment (PTS), and subsequently ranges to effects for TTS and behavioral exposures, based on the new Guidance to assess if the new impulsive criteria could result in any additional species-specific takes. The conclusion from that analysis was that the new impulsive criteria would not change previous species-specific quantities of impulsive PTS, TTS, or behavioral exposures for any species except Dall's porpoise, and the mitigation zones described in the proposed rule (as shown in Mitigation Zones ) for each type of explosives training activity remain sufficiently protective ( i.e., mitigation zones encompass newly calculated PTS zones for all explosive types and hearing groups). Consideration of the new Guidance results in an increase in take for Dall's porpoise by 3 Level A and 149 Level B harassment takes (12 TTS and 137 behavioral reactions) above what is described in Alternative 1 of the FEIS/OEIS. These updated take numbers are included in the “Take Request” section. In summary, NMFS' consideration of the new Guidance does not substantially alter our assessment of the likely responses of marine mammals to acoustic sources employed by the Navy in the GOA TMAA Study Area (though take numbers have been altered slightly where appropriate as described above and in the Estimated Take section), or the likely fitness consequences of those responses. Overall, predicted auditory effects within this rulemaking would not change significantly. As described, application of the new Guidance represents only minor changes in take estimates, and would not change NMFS' final analysis and negligible impact determination. Further, the robust monitoring and mitigation measures in this final rule satisfy the “least practicable adverse impact” standard. Of additional note, the definition of an “Unusual Mortality Event,” which is necessary to the implementation of the Navy's Stranding Response Plan, has been added to the final regulations. This addition corrects an oversight in the proposed rule and does not represent a significant change. Background of Request The Navy's mission is to organize, train, equip, and maintain combat-ready naval forces capable of winning wars, deterring aggression, and maintaining freedom of the seas. Consistent with this mission, 10 U.S.C. 5062 mandates that naval forces be trained and equipped for prompt and sustained combat incident to operations at sea, and that naval forces be prepared for the effective prosecution of war. 1 The Navy executes this responsibility by establishing and executing training programs, including at-sea training and exercises, and ensuring naval forces have access to the ranges, operating areas (OPAREAs), and airspace needed to develop and maintain skills for conducting military readiness activities. 1 Title 10, Section 5062 of the U.S.C. The Navy proposes to continue conducting training activities within the Study Area, which have been ongoing since the 1990s. The tempo and types of training activities have evolved and fluctuated to some degree because of the introduction of new technologies, the dynamic nature of international events, advances in war fighting doctrine and procedures, and force structure (organization of ships, submarines, aircraft, weapons, and personnel) changes. Such developments influence the frequency, duration, intensity, and location of required training activities, but the essential character and basic level of the military readiness activities conducted in the Study Area has remained largely unchanged. The Navy's LOA request covers training activities that would occur over a five-year period beginning in May 2017. NMFS' previous MMPA incidental take authorization for the GOA TMAA expired in May 2016. Description of the Specified Activity The proposed rule (81 FR 9950; February 26, 2016) and GOA FSEIS/OEIS include a complete description of the Navy's specified training activities incidental to which NMFS is authorizing take of marine mammals in this final rule. Sonar use and underwater detonations are the stressors most likely to result in impacts on marine mammals that could rise to the level of harassment. Detailed descriptions of these activities are provided in the FSEIS/OEIS and in the LOA application ( http://www.nmfs.noaa.gov/pr/permits/incidental/military.htm ) and are summarized here. Overview of Training Activities The Navy routinely trains in the Study Area in preparation for national defense missions. Training activities and exercises covered in the Navy's LOA request are briefly described below, and in more detail within chapter 2 of the GOA FSEIS/OEIS. Each military training activity described meets a requirement that can be traced ultimately to requirements set forth by the National Command Authority. 2 2 “National Command Authority” is a term used by the United States military and government to refer to the ultimate lawful source of military orders. The term refers collectively to the President of the United States (as commander-in-chief) and the United States Secretary of Defense. The Navy categorizes training activities into eight functional warfare areas called primary mission areas: Anti-air warfare; amphibious warfare; strike warfare; Anti-surface warfare (ASUW); anti-submarine warfare (ASW); electronic warfare; mine warfare (MIW); and naval special warfare (NSW). Most training activities are categorized under one of these primary mission areas; those activities that do not fall within one of these areas are in a separate “other” category. Each warfare community (surface, subsurface, aviation, and special warfare) may train within some or all of these primary mission areas. However, not all primary mission areas are conducted within the Study Area. The Navy described and analyzed the effects of its training activities within the GOA FSEIS/OEIS. In its assessment, the Navy concluded that of the activities conducted within the Study Area, sonar use and underwater detonations were the stressors resulting in impacts on marine mammals that could rise to the level of harassment as defined under the MMPA. Therefore, the LOA application provides the Navy's assessment of potential effects from these stressors. The specific acoustic sources used in the LOA application are contained in the GOA FSEIS/OEIS and are presented in the following sections based on the primary mission areas. Anti-Surface Warfare (ASUW) The mission of ASUW is to defend against enemy ships or boats. In the conduct of ASUW, aircraft use cannons, air-launched cruise missiles or other precision-guided munitions; ships employ torpedoes, naval guns, and surface-to-surface (S-S) missiles; and submarines attack surface ships using torpedoes or submarine-launched, anti-ship cruise missiles. Anti-surface warfare training in the Study Area includes S-S gunnery and missile exercises (GUNEX and MISSILEX) and air-to-surface (A-S) bombing exercises (BOMBEX), GUNEX, and MISSILEX. Of note, the MISSILEX in GOA does not expend ordnance. Anti-Submarine Warfare (ASW) The mission of ASW is to locate, neutralize, and defeat hostile submarine threats to surface forces. ASW is based on the principle of a layered defense of surveillance and attack aircraft, ships, and submarines all searching for hostile submarines. These forces operate together or independently to gain early warning and detection, and to localize, track, target, and attack hostile submarine threats. Anti-submarine warfare training addresses basic skills such as detection and classification of submarines, distinguishing between sounds made by enemy submarines and those of friendly submarines, ships, and marine life. ASW training evaluates the ability of fleet assets to use systems, for example, active and passive sonar and torpedo systems to counter hostile submarine threats. More advanced, integrated ASW training exercises are conducted in coordinated, at-sea training events involving submarines, ships, and aircraft. This training integrates the full spectrum of ASW from detecting and tracking a submarine to attacking a target using simulated weapons. Description of Sonar, Ordnance, Targets, and Other Systems The Navy uses a variety of sensors, platforms, weapons, and other devices to meet its mission. Training with these systems and devices may introduce acoustic (sound) energy into the environment. The Navy's current LOA application describes underwater sound as one of two types: Impulsive and non-impulsive. Sonar and similar sound producing systems are categorized as non-impulsive sound sources. Underwater detonations of explosives and other percussive events are impulsive sounds. Sonar and Other Active Acoustic Sources Modern sonar technology includes a variety of sonar sensor and processing systems. In concept, the simplest active sonar emits sound waves, or “pings,” sent out in multiple directions, and the sound waves then reflect off of the target object in multiple directions. The sonar source calculates the time it takes for the reflected sound waves to return; this calculation determines the distance to the target object. More sophisticated active sonar systems emit a ping and then rapidly scan or listen to the sound waves in a specific area. This provides both distance to the target and directional information. Even more advanced sonar systems use multiple receivers to listen to echoes from several directions simultaneously and provide efficient detection of both direction and distance. Active sonar is rarely used continuously throughout the listed activities. In general, when sonar is in use, the sonar “pings” occur at intervals, referred to as a duty cycle, and the signals themselves are very short in duration. For example, sonar that emits a 1-second ping every 10 seconds has a 10 percent duty cycle. The Navy's largest hull-mounted mid-frequency sonar source typically emits a 1-second ping every 50 seconds representing a 2 percent duty cycle. The Navy utilizes sonar systems and other acoustic sensors in support of a variety of mission requirements. Primary uses include the detection of and defense against submarines (ASW) and mines (MIW); safe navigation and effective communications; use of unmanned undersea vehicles; and oceanographic surveys. Sources of sonar and other active acoustic sources include surface ship sonar, sonobuoys, torpedoes, and unmanned underwater vehicles. Ordnance and Munitions Most ordnance and munitions used during training events fall into three basic categories: Projectiles (such as gun rounds), missiles (including rockets), and bombs. Ordnance can be further defined by their net explosive weight (NEW), which considers the type and quantity of the explosive substance without the packaging, casings, bullets, etc. NEW is the trinitrotoluene (TNT) equivalent of energetic material, which is the standard measure of strength of bombs and other explosives. For example, a 5-inch shell fired from a Navy gun is analyzed at approximately 9.5 pounds (lb.) (4.3 kilograms (kg)) of NEW. The Navy also uses non-explosive ordnance in place of explosive ordnance in many training and testing events. Non-explosive ordnance look and perform similarly to explosive ordnance, but lack the main explosive charge. Defense Countermeasures Naval forces depend on effective defensive countermeasures to protect themselves against missile and torpedo attack. Defensive countermeasures are devices designed to confuse, distract, and confound precision-guided munitions. Defensive countermeasures analyzed in this LOA application include acoustic countermeasures, which are used by surface ships and submarines to defend against torpedo attack. Acoustic countermeasures are either released from ships and submarines, or towed at a distance behind the ship. Classification of Non-Impulsive and Impulsive Sources Analyzed In order to better organize and facilitate the analysis of approximately 300 individual sources of underwater acoustic sound or explosive energy, a series of source classifications, or source bins, were developed by the Navy. The use of source classification bins provides the following benefits: • Provides the ability for new sensors or munitions to be covered under existing regulatory authorizations, as long as those sources fall within the parameters of a “bin”; • Simplifies the source utilization data collection and reporting requirements anticipated under the MMPA; • Ensures a conservative approach to all impact analysis, as all sources in a single bin are modeled as the loudest source ( e.g., lowest frequency, highest source level (the term “source level” refers to the loudness of a sound at its source), longest duty cycle, or largest NEW) within that bin, which: ○ Allows analysis to be conducted more efficiently, without compromising the results; and ○ Provides a framework to support the reallocation of source usage (hours/explosives) between different source bins, as long as the total number and severity of marine mammal takes remain within the overall analyzed and authorized limits. This flexibility is required to support evolving Navy training requirements, which are linked to real world events. There are two primary types of acoustic sources: Impulsive and non-impulsive. A description of each source classification is provided in Tables 1 and 2. Impulsive source class bins are based on the NEW of the munitions or explosive devices or the source level for air and water guns. Non-impulsive acoustic sources are grouped into source class bins based on the frequency, 3 source level, 4 and, when warranted, the application in which the source would be used. The following factors further describe the considerations associated with the development of non-impulsive source bins. 3 Bins are based on the typical center frequency of the source. Although harmonics may be present, those harmonics would be several decibels (dB) lower than the primary frequency. 4 Source decibel levels are expressed in terms of sound pressure level (SPL) and are values given in dB referenced to 1 micropascal at 1 meter. • Frequency of the non-impulsive source: ○ Low-frequency sources operate below 1 kilohertz (kHz); ○ Mid-frequency sources operate at and above 1 kHz, up to and including 10 kHz; ○ High-frequency sources operate above 10 kHz, up to and including 100 kHz; ○ Very high-frequency sources operate above 100 kHz but below 200 kHz. • Source level of the non-impulsive source; ○ Greater than 160 decibels (dB), but less than 180 dB; ○ Equal to 180 dB and up to 200 dB; ○ Greater than 200 dB. • Application in which the source would be used; ○ How a sensor is employed supports how the sensor's acoustic emissions are analyzed; ○ Factors considered include pulse length (time source is on); beam pattern (whether sound is emitted as a narrow, focused beam or, as with most explosives, in all directions); and duty cycle (how often or how many times a transmission occurs in a given time period during an event). As described in the GOA FSEIS/OEIS, non-impulsive acoustic sources that have low source levels (not loud), narrow beam widths, downward directed transmission, short pulse lengths, frequencies beyond known hearing ranges of marine mammals, or some combination of these characteristics, are not anticipated to result in takes of protected species and therefore were not modeled. These sources generally meet one of the following criteria, are considered de mimimis sources, and are qualitatively analyzed in the GOA FSEIS/OEIS: • Acoustic sources with frequencies greater than 200 kHz (based on known marine mammal hearing ranges); and • Sources with source levels less than 160 dB. Source Classes Analyzed for Training Table 1 shows the impulsive sources ( e.g., underwater explosives) associated with training activities analyzed in the Study Area, as proposed in the Navy's LOA request and described in the proposed rule. Alternative 1 of the FSEIS/OEIS, the specific activity for which the incidental taking of marine mammals is authorized pursuant to this final rule, includes zero detonations from the E6, E7, E8, and E11 source bins, as indicated in Table 1. Table 2 shows non-impulsive sources ( e.g., sonar) associated with training activities analyzed in the Study Area, as proposed in the Navy's LOA request and described in the proposed rule. Alternative 1 of the FSEIS/OEIS includes zero torpedoes from the TORP2 category, as indicated in Table 2. Additionally, Alternative 1 does not include live MISSILEX exercises, which were included in the proposed rule. Table 1—Impulsive (Explosive) Training Source Classes Analyzed Quantitatively Source class Representative munitions Net explosive weight (lbs.) E5 5-inch projectiles >5-10 E6 * AGM-114 Hellfire missile >10-20 E7 * AGM-88 High-speed Anti-Radiation Missile >20-60 E8 * 250 lb. bomb >60-100 E9 500 lb. bomb >100-250 E10 1,000 lb. bomb >250-500 E11 * MK-48 torpedo >500-650 E12 2,000 lb. bomb >650-1,000 * Note— these bins are not covered by this final rule, since Navy reduced their proposed activity in their incidental take request. Table 2—Non-Impulsive Training Source Classes Analyzed Quantitatively Source class category Source class Description of representative sources Mid-Frequency (MF): Tactical and non-tactical sources that produce mid-frequency (1-10 kHz) signals MF1 Hull-mounted surface ship sonar ( e.g., AN/SQS-53C and AN/SQS-60). MF3 Hull-mounted submarine sonar ( e.g., AN/BQQ-10). MF4 Helicopter-deployed dipping sonar ( e.g., AN/AQS-22 and AN/AQS-13). MF5 Active acoustic sonobuoys ( e.g., DICASS). MF6 Active underwater sound signal devices ( e.g., MK-84). MF11 Hull-mounted surface ship sonar with an active duty cycle greater than 80%. High-Frequency (HF): Tactical and non-tactical sources that produce high-frequency (greater than 10 kHz but less than 100 kHz) signals HF1 Hull-mounted submarine sonar ( e.g., AN/BQQ-10). HF6 Active sources (equal to 180 dB and up to 200 dB). Anti-Submarine Warfare (ASW): Tactical sources such as active sonobuoys and acoustic countermeasures systems used during the conduct of ASW training activities ASW2 Mid-frequency Multistatic Active Coherent sonobuoy ( e.g., AN/SSQ-125). ASW3 Mid-frequency towed active acoustic countermeasure systems ( e.g., AN/SLQ-25). ASW4 Mid-frequency expendable active acoustic device countermeasures ( e.g., MK-3). * Torpedoes (TORP): Source classes associated with the active acoustic signals produced by torpedoes TORP2 Heavyweight torpedo ( e.g., MK-48, electric vehicles). Notes: dB = decibels, DICASS = Directional Command Activated Sonobuoy System, kHz = kilohertz. * TORP not covered by this rule since Navy reduced their activities. Training The training activities with potential impacts to marine mammals that the Navy proposes to conduct in the Study Area are described in Table 3. The table is organized according to primary mission areas and includes the activity name, associated stressor(s), description of the activity, the primary platform used ( e.g., ship or aircraft type), duration of activity, type of non-impulsive or impulsive sources used in the activity, and the number of activities per year. More detailed activity descriptions can be found in chapter 2 of the GOA FSEIS/OEIS. The Navy's activities are anticipated to meet training needs in the years 2017-2022. Table 3—Training Activities Within the Study Area. Activities Now Reflect Navy's Alternative 1, Which No Longer Includes Sinking Exercises and Includes One, Instead of Two, CSG Exercises Category Training activity Description Weapons/rounds/sound source Anti-Surface Warfare (ASUW) Impulsive Gunnery Exercise, Surface-to-Surface (Ship) (GUNEX-S-S (Ship)) Ship crews engage surface targets with ship's small-, medium-, and large-caliber guns Small-, Medium-, and Large-caliber high explosive rounds. Impulsive Bombing Exercise (Air-to-Surface) (BOMBEX (A-S)) Fixed-wing aircrews deliver bombs against surface targets High explosive bombs. Anti-Submarine Warfare (ASW) Non-impulsive Tracking Exercise—Submarine (TRACKEX—Sub) Submarine searches for, detects, and tracks submarine(s) and surface ship(s) Mid- and high-frequency submarine sonar. Non-impulsive Tracking Exercise—Surface (TRACKEX—Surface) Surface ship searches for, tracks, and detects submarine(s) Mid-frequency surface ship sonar, acoustic countermeasures, and high-frequency active sources. Non-impulsive Tracking Exercise—Helicopter (TRACKEX—Helo) Helicopter searches, tracks, and detects submarine(s) Mid-frequency dipping sonar systems and sonobuoys. Non-impulsive Tracking Exercise—Maritime Patrol Aircraft (TRACKEX—MPA) Maritime patrol aircraft use sonobuoys to search for, detect, and track submarine(s) Sonobuoys, such as DICASS sonobuoys. Non-impulsive Tracking Exercise—Maritime Patrol Aircraft (MAC Sonobuoys) Maritime patrol aircraft crews search for, detect and track submarines using MAC sonobuoys mid-frequency MAC sonobuoys. Notes: DICASS = Directional Command Activated Sonobuoy System; MAC=Multistatic Active Coherent. Summary of Impulsive and Non-Impulsive Sources Table 4 provides a quantitative annual summary of training activities by sonar and other active acoustic source class analyzed in the Navy's LOA request. Annual use has been updated since publication of the notice for the proposed rule and now reflects Navy's Alternative 1, which results in a reduction of annual use by about half. Table 4—Annual Hours and Units of Sonar and Other Active Acoustic Sources Used During Training Within the Study Area Source class category Source class Units Annual use Mid-Frequency (MF) Active sources from 1 to 10 kHz MF1 MF3 MF4 Hours Hours Hours 271 24 26 MF5 * MF6 MF11 Items Items Items 126 11 39 High-Frequency (HF): Tactical and non-tactical sources that produce signals greater than 10 kHz but less than 100 kHz HF1 HF6 Hours Hours 12 40 Anti-Submarine Warfare (ASW) Active ASW sources ASW2 ASW3 ASW4 * Hours Hours Items 40 273 6 Torpedoes (TORP) Source classes associated with active acoustic signals produced by torpedoes TORP2 Items 0 * Annual use for MF5 and ASW4 was incorrectly identified in the proposed rule as 25 and 4, respectively. Annual use for these source classes is 252 and 12, respectively, for Alternative 2—but is half that here, reflecting Alternative 1. Table 5 provides a quantitative annual summary of training explosive source classes analyzed in the Navy's LOA request. Annual number of in-water detonations has been updated since publication of the notice for the proposed rule and now reflects Navy's Alternative 1, which results in a reduction of detonations by at least half. Table 5—Annual Number of Training Explosive Source Detonations Used During Training Within the Study Area Explosive class net explosive weight (pounds (lb.)) Annual in-water detonations training E5 (>5-10 lb.) 56 E6 (>10-20 lb.) 0 E7 (>20-60 lb.) 0 E8 (>60-100 lb.) 0 E9 (>100-250 lb.) 64 E10 (>250-500 lb.) 6 E11 (>500-650 lb.) 0 E12 (>650-1,000 lb.) 2 Duration and Location Training activities would be conducted in the Study Area during one exercise of up to 21 days per year between the months of April and October to support a major joint training exercise in Alaska and off the Alaskan coast that involves the Departments of the Navy, the Army, Air Force, and the U.S. Coast Guard (Coast Guard). The Service participants report to a unified or joint commander who coordinates the activities planned to demonstrate and evaluate the ability of the services to engage in a conflict and carry out plans in response to a threat to national security. Take incidental to the annual exercise would be authorized between May 2017 and May 2022. The Study Area (see Figure 1-1 of the LOA application) is entirely at sea and is composed of the established GOA TMAA and a warning area in the Gulf of Alaska. The Navy uses “at-sea” to include its training activities in the Study Area that occur (1) on the ocean surface, (2) beneath the ocean surface, and (3) in the air above the ocean surface. Navy training activities occurring on or over the land outside the GOA TMAA are covered under previously prepared environmental documentation prepared by the U.S. Air Force and the U.S. Army. Gulf of Alaska Temporary Maritime Activities Area (GOA TMAA) The GOA TMAA is a temporary area established in conjunction with the Federal Aviation Administration (FAA) for one exercise period of up to 21 days, that is a surface, undersea space, and airspace maneuver area within the Gulf of Alaska for ships, submarines, and aircraft to conduct required training activities. The GOA TMAA is a polygon roughly resembling a rectangle oriented from northwest to southeast, approximately 300 nautical miles (nm) in length by 150 nm in width, located south of Prince William Sound and east of Kodiak Island. Airspace of the GOA TMAA The airspace of the GOA TMAA overlies the surface and subsurface training area and is called an Altitude Reservation (ALTRV). This ALTRV is a temporary airspace designation, typically requested by the Alaskan Command (ALCOM) and coordinated through the FAA for the duration of the exercise. This overwater airspace supports the majority of aircraft training activities conducted by Navy and Joint aircraft throughout the joint training exercise. The ALTRV over the GOA TMAA typically extends from the ocean surface to 60,000 feet (ft) (18,288 meters (m)) above mean sea level and encompasses 42,146 square nautical miles (nm 2 ) of airspace. For safety considerations, ALTRV information is sent via Notice to Airmen (NOTAM)/International NOTAM so that all pilots are aware of the area and that Air Traffic Control will keep known Instrument Flight Rules aircraft clear of the area. Additionally, the GOA TMAA overlies a majority of Warning Area W-612 (W-612) located over Blying Sound, towards the northwestern quadrant of the GOA TMAA. When not included as part of the GOA TMAA, W-612 provides 2,256 nm 2 of special use airspace for the Air Force and Coast Guard to fulfill some of their training requirements. Air Force, Army, National Guard, and Coast Guard activities conducted as part of at-sea joint training within the GOA TMAA are included in the FSEIS/OEIS analysis. No Navy training activities analyzed in this final rule occur in the area of W-612 that is outside of the GOA TMAA (see Figure 1-1 of the LOA application). Sea and Undersea Space of the GOA TMAA The GOA TMAA surface and subsurface areas are also depicted in Figure 1-1 of the LOA application. Total surface area of the GOA TMAA is 42,146 nm 2 . Due to weather conditions, annual joint training activities are typically conducted during the summer months (April-October). The GOA TMAA undersea area lies beneath the surface area as depicted in Figure 1-1 of the LOA application. The undersea area extends to the seafloor. The complex bathymetric and oceanographic conditions, including a continental shelf, submarine canyons, numerous seamounts, and fresh water infusions from multiple sources, create a challenging environment in which to search for and detect submarines in ASW training activities. In the summer, the GOA TMAA provides a safe cold-water training environment that resembles other areas where Navy may need to operate in a real-world scenario. The GOA TMAA meets large-scale joint exercise training objectives to support naval and joint operational readiness by providing a “geographically realistic” training area for U.S. Pacific Command, Joint Task Force Commander scenario-based training, and supports the mission requirement of Alaskan Command (ALCOM) to conduct joint training for Alaska-based forces. The strategic vision of the Commander, U.S. Pacific Fleet is that the training area supports naval operational readiness by providing a realistic, live-training environment for forces assigned to the Pacific Fleet and other users with the capability and capacity to support current, emerging, and future training requirements. Description of Marine Mammals in the Area of the Specified Activities Twenty-two marine mammal species have confirmed or possible occurrence within or adjacent to the Study Area, including seven species of baleen whales (mysticetes), eight species of toothed whales (odontocetes), six species of seals (pinnipeds), and the sea otter (mustelid). Three of these species (gray whale, sea otter, and ribbon seal) are not expected to be taken by the training activities, as discussed in Chapter 4 of the LOA application. Nine of these species are listed under the ESA: Blue whale, fin whale, humpback whale (Distinct Population Segment (DPS) and Western North Pacific DPS), sei whale, sperm whale, gray whale (Western North Pacific stock), North Pacific right whale, Steller sea lion (Western U.S. stock), and sea otter. The “Description of Marine Mammals in the Area of the Specified Activities” section was included in the proposed rule (81 FR 9950, 9956-57; February 26, 2016). These descriptions have not changed, with the exception of the humpback whale. On September 8, 2016, NMFS revised the ESA listing for humpback whales to identify 14 DPSs, listing one as threatened, four as endangered, and identifying nine others as not warranted for listing (81 FR 40870). Humpback whales from the threatened Mexico DPS, endangered Western North Pacific DPS, and Hawaii DPS, which was identified as not warranted for listing, could all occur in the Study Area. Table 6 of the proposed rule provided a list of marine mammals with possible or confirmed occurrence within the GOA TMAA Study Area, including stock, abundance, and status. Information on the status, distribution, abundance, and vocalizations of marine mammal species in the Study Area may also be viewed in Chapter 4 of the LOA application ( http://www.nmfs.noaa.gov/pr/permits/incidental/military.htm ). Additional information on the general biology and ecology of marine mammals is included in the GOA FSEIS/OEIS. In addition, NMFS annually publishes Stock Assessment Reports (SARs) for all marine mammals in U.S. EEZ waters, including stocks that occur within the Study Area (U.S. Pacific Marine Mammal Stock Assessments, Carretta et al., 2015; Alaska Marine Mammal Stock Assessments, Muto and Angliss, 2015). Potential Effects of Specified Activities on Marine Mammals In the “Potential Effects of Specified Activities on Marine Mammals” section of the proposed rule (81 FR 9950; 9961-78; February 26, 2016), we included a qualitative discussion of the different ways that Navy training activities may potentially affect marine mammals without consideration of mitigation and monitoring measures. With the exception of the new information related to thresholds for auditory injury described earlier in this document, that information has not changed in a manner that would affect our analysis or findings and is not repeated here. Mitigation Under section 101(a)(5)(A) of the MMPA, NMFS must set forth the “permissible methods of taking pursuant to such activity, and other means of effecting the least practicable adverse impact on such species or stock and its habitat, paying particular attention to rookeries, mating grounds, and areas of similar significance, and on the availability of such species or stock for subsistence uses” (“least practicable adverse impact”). NMFS does not have a regulatory definition for least practicable adverse impact. The NDAA for FY 2004 amended the MMPA as it relates to military readiness activities and the incidental take authorization process such that “least practicable adverse impact” shall include consideration of personnel safety, practicality of implementation, and impact on the effectiveness of the “military readiness activity.” As discussed in the proposed rule, in Conservation Council for Hawaii v. National Marine Fisheries Service, 97 F. Supp.3d 1210, 1229 (D. Haw. Mar. 31, 2015), the court stated that NMFS “appear[s] to think [it] satisf[ies] the statutory `least practicable adverse impact' requirement with a `negligible impact' finding.” Following publication of the proposed rule, the Ninth Circuit Court of Appeals in Natural Resources Defense Council v. Pritzker, 828 F.3d 1125, 1134 (9th Cir. July 15, 2016), expressing similar concerns in a challenge to our last SURTASS LFA sonar incidental take rule, stated, “Compliance with the `negligible impact' requirement does not mean there [is] compliance with the `least practicable adverse impact standard [. . .] .” As the Ninth Circuit noted in its opinion, however, the court was interpreting the statute without the benefit of NMFS' formal interpretation. We state here explicitly, as we have said in the past, that NMFS is in full agreement that the “negligible impact” and “least practicable adverse impact” requirements are distinct, even though both statutory standards refer to species and stocks. With that in mind, we provide further explanation of our interpretation of least practicable adverse impact, and explain what distinguishes it from the negligible impact standard. This discussion is consistent with, and expands upon, previous rules we have issued and the explanation provided in the proposed rule. Before NMFS can issue incidental take regulations under section 101(a)(5)(A) of the MMPA, it must make a finding that the total taking will have a “negligible impact” on the affected “species or stocks” of marine mammals. NMFS' and U.S. Fish and Wildlife Service's joint implementing regulations for section 101(a)(5)(A) define “negligible impact” as “an impact resulting from the specified activity that cannot be reasonably expected to, and is not reasonably likely to, adversely affect the species or stock through effects on annual rates of recruitment or survival.” 50 CFR 216.103 and 50 CFR 18.27(c). Recruitment ( i.e., reproduction) and survival rates are used to determine population growth rates 5 and, therefore are considered in evaluating population level impacts. 5 A growth rate can be positive, negative, or flat. As we stated in the preamble to the final rule for the joint implementing regulations, not every population-level impact violates the negligible impact requirement. The negligible impact standard does not require a finding that the anticipated take will have “no effect” on population numbers or growth rates: “The statutory standard does not require that the same recovery rate be maintained, rather that no significant effect on annual rates of recruitment or survival occurs [. . .] . [T]he key factor is the significance of the level of impact on rates of recruitment or survival.” See 54 FR 40338, 40341-42 (September 29, 1989). While some level of impact on population numbers or growth rates of a species or stock may occur and still satisfy the negligible impact requirement—even without consideration of mitigation—the least practicable adverse impact provision separately requires NMFS to prescribe the means of “effecting the least practicable adverse impact on such species or stock and its habitat, paying particular attention to rookeries, mating grounds, and areas of similar significance [. . .].” 6 7 6 For purposes of this discussion we omit reference to the language in the standard for least practicable adverse impact that says we also must mitigate for subsistence impacts because they are not at issue in this action. 7 NMFS' incidental take actions routinely refer to the least practicable adverse impact requirement in shorthand as “mitigation,” a concept that broadly encompasses measures or practices that are reasonably designed to avoid, reduce, or minimize impacts. The negligible impact and least practicable adverse impact standards in the statute share a common reference to “species or stocks.” A “species” is defined as a group of animals or plants that are similar and can produce young animals or plants: a group of related animals or plants that is smaller than a genus ( http://www.merriam-webster.com/dictionary/species ). “Population stock” or “stock” means “a group of marine mammals of the same species or smaller taxa in a common spatial arrangement, that interbreed when mature.” 16 U.S.C. 1362(11). We believe those terms indisputably refer to populations of animals, and that it is therefore appropriate to view both MMPA provisions as having a population-level focus. This is consistent with both the language of the statute and Congress' overarching conservation objective in enacting the MMPA. See 16 U.S.C. 1361 (Congress' findings reflecting policy concerns about the extinction or depletion of certain marine mammal species or stocks and the goal of ensuring they are functioning elements of their ecosystems). Recognizing this common focus of the two provisions on “species or stock” does not mean we conflate the standards; despite some common statutory language, we recognize the two provisions are different in other ways and have different functions. 8 First, a negligible impact finding is required before NMFS can issue an incidental take authorization. Although it is acceptable to use mitigation to reach a negligible impact finding, 50 CFR 216.104(c), no amount of mitigation can enable NMFS to issue an incidental take authorization for an activity that still would not meet the negligible impact standard. Moreover, even where NMFS can reach a negligible impact finding—which we emphasize does allow for the possibility of some “negligible” population-level impact—the agency must still prescribe practicable measures that will effect the least amount of adverse impact upon the affected species or stock. 8 See also CBD v. Salazar, 695 F.3d 893 (9th Cir. 2012) (finding that some overlap between FWS' factors for determining negligible impact and small numbers was not an improper conflation of the two standards where the agency also considered other factors in reaching its conclusions). Further, section 101(a)(5)(A)(i)(II) requires NMFS to issue, in conjunction with its authorization, binding—and enforceable—restrictions (in the form of regulations) setting forth how the activity must be conducted, thus ensuring the activity has the “least practicable adverse impact” on the affected species or stocks. In situations where mitigation is needed to reach a negligible impact determination, section 101(a)(5)(A)(i)(II) also provides a mechanism for ensuring compliance with the “negligible impact” requirement. Finally, we also reiterate that the “least practicable adverse impact” standard requires mitigation for marine mammal habitat, with particular attention to rookeries, mating grounds, and other areas of similar significance, and for mitigating subsistence impacts; whereas the negligible impact standard is concerned with conclusions about the impact of an activity on the affected populations. 9 9 Outside of the military readiness context, mitigation may also be appropriate to ensure compliance with the “small numbers” language in MMPA sections 101(a)(5)(A) and (D). In NRDC v. Pritzker, the court stated, “[t]he statute is properly read to mean that even if population levels are not threatened significantly, still the agency must adopt mitigation measures aimed at protecting marine mammals to the greatest extent practicable in light of military readiness needs.” Id. at 1134 (emphasis added). This statement is consistent with our understanding stated above that even when the effects of an action satisfy the negligible impact standard ( i.e., in the court's words, “population levels are not threatened significantly”), still the agency must prescribe mitigation under the least practicable adverse impact standard. However, as the statute indicates, the focus of both standards is ultimately the impact on the affected “species or stock,” and not solely focused on/directed at the impact on individual marine mammals. We have carefully reviewed and considered the Ninth Circuit's opinion in NRDC v. Pritzker in its entirety. While the court's reference to “marine mammals” rather than “marine mammal species or stocks” in the italicized language above might be construed as a holding that the least practicable adverse impact standard applies at the individual “marine mammal” level, i.e., that NMFS must require mitigation to minimize impacts to each individual marine mammal unless impracticable, we believe such an interpretation reflects an incomplete appreciation of the court's holding. In our view, the opinion as a whole turned on the court's determination that NMFS had not given separate and independent meaning to the least practicable adverse impact standard apart from the negligible impact standard, and further that the court's use of the term “marine mammals” was not addressing the question of whether the standard applies to individual animals as opposed to the species or stock as a whole. We recognize that while consideration of mitigation can play a role in a negligible impact determination, consideration of mitigation extends beyond that analysis. In evaluating what mitigation is appropriate, NMFS considers the impacts of the proposed action, the availability of measures to minimize those potential impacts, and the practicability of implementing those measures, as we describe below. Implementation of Least Practicable Adverse Impact Given this most recent court decision, we further clarify how we determine whether a measure or set of measures meets the “least practicable adverse impact” standard. Our evaluation of potential mitigation measures includes consideration of two primary factors: (1) The manner in which, and the degree to which, implementation of the measure(s) is expected to reduce impacts to marine mammal species or stocks, their habitat, and their availability for subsistence uses (where relevant). Among other things, this analysis will consider the nature of the potential adverse impact (such as likelihood, scope, and range), the likelihood that the measure will be effective if implemented, and the likelihood of successful implementation. (2) The practicability of the measures for applicant implementation. Practicability of implementation may consider such things as cost, impact on operations, and, in the case of a military readiness activity, personnel safety, practicality of implementation, and impact on the effectiveness of the military readiness activity. 16 U.S.C. 1371(a)(5)(A)(ii). While the language of the least practicable adverse impact standard calls for minimizing impacts to affected species or stocks, we recognize that the reduction of impacts to those species or stocks accrues through the application of mitigation measures that limit impacts to individual animals. Accordingly, NMFS' analysis will focus on measures designed to avoid or minimize impacts on marine mammals from activities that are likely to increase the probability or severity of population-level effects. While direct evidence of impacts to species or stocks from a specified activity is rarely available, and additional study is still needed to describe how specific disturbance events affect the fitness of individuals of certain species, there have been improvements in understanding the process by which disturbance effects are translated to the population. With recent scientific advancements (both marine mammal energetic research and the development of energetic frameworks), the relative likelihood or degree of impacts on species or stocks may often be inferred given a detailed understanding of the activity, the environment, and the affected species or stocks. This same information is used in the development of mitigation measures and helps us understand how mitigation measures contribute to lessening species or stock effects. In the evaluation of specific measures, the details of the specified activity will necessarily inform each of the two factors and will be carefully considered to determine the types of mitigation that are appropriate under the least practicable adverse impact standard. The greater the likelihood that a measure will contribute to reducing the probability or severity of adverse impacts to the species or stock, the greater the weight that measure(s) is given when considered in combination with practicability to determine the appropriateness of the mitigation measure(s), and vice versa. Below we discuss how these factors are considered. 1. Reduction of adverse impacts to species or stock. The emphasis given to a measure's ability to reduce the impacts on a species or stock considers the degree, likelihood, and context of the anticipated reduction of impacts to individuals as well as the status of the species or stock. The ultimate impact on any individual from a disturbance event (which informs the likelihood of adverse species or stock-level effects) is dependent on the circumstances and associated contextual factors, such as duration of exposure to stressors. Though any proposed mitigation needs to be evaluated in the context of the specific activity and the species or stocks affected, measures with the following types of goals are often applied to reduce the likelihood or severity of adverse species or stock-level impacts: Avoiding or minimizing injury or mortality; limiting interruption of known feeding, breeding, mother/young, or resting behaviors; minimizing the abandonment of important habitat (temporally and spatially); minimizing the number of individuals subjected to these types of disruptions; and limiting degradation of habitat. Mitigating these types of effects is intended to reduce the likelihood that the activity will result in energetic or other types of impacts that are more likely to result in reduced reproductive success or survivorship. It is also important to consider the degree of impacts that were expected in the absence of mitigation in order to assess the added value of any potential measures. The status of the species or stock is also relevant in evaluating the appropriateness of certain mitigation measures in the context of least practicable adverse impact. The following are examples of factors that may (either alone, or in combination) result in greater emphasis on the importance of a mitigation measure in reducing impacts on a species or stock: The stock is known to be decreasing or status is unknown, but believed to be declining; the known annual mortality (from any source) is approaching or exceeding the potential biological removal (PBR) level (as defined in 16 U.S.C. 1362(20)); the affected species or stock is a small, resident population; or the stock is involved in an unusual mortality event (UME) or has other known vulnerabilities, such as recovering from an oil spill. Reduction of habitat impacts. Habitat mitigation, particularly as it relates to rookeries, mating grounds, and areas of similar significance, is also relevant and can include measures, such as reducing impacts of the activity on known prey utilized in the activity area or reducing impacts on physical habitat. Likely effectiveness of the measure. We consider available information indicating the likelihood of any measure to accomplish its objective. If evidence shows that a measure has not typically been effective or successful, then either that measure should be modified, or the potential value of the measure to reduce effects is lowered. 2. Practicability. Factors considered may include cost, impact on operations, and, in the case of a military readiness activity, personnel safety, practicality of implementation, and impact on the effectiveness of the military readiness activity. 16 U.S.C. 1371(a)(5)(A)(ii). The above section describes the factors considered in making a least practicable adverse impact finding. In summary, NMFS will carefully balance the likelihood and degree to which a measure(s) will reduce adverse impacts on species or stocks with the measure's practicability in determining appropriate mitigation measures. NMFS reviewed the proposed activities and the proposed mitigation measures as described in the Navy's LOA application to determine if they would result in the least practicable adverse effect on marine mammal species or stocks. NMFS described the Navy's proposed mitigation measures in detail in the proposed rule (81 FR 9950, 9978-86; February 26, 2016). As described below and in responses to comments, and in the GOA FSEIS/OEIS, some additional measures were also considered and analyzed. Time/area specific mitigation measures considered by the Navy and NMFS for the Navy's low use of hull-mounted mid-frequency active sonar and explosives activities in certain areas of particular importance to specific marine mammals have been clarified and described below (see “Consideration of Time/Area Limitations”) and in the “Comments and Responses” section of this rule. This final rule includes the adoption of a new “Cautionary Area” for North Pacific right whales. This additional time/area specific measure is also included in the regulatory text (see § 218.154 Mitigation) at the end of this rule. Other additional mitigation measures were considered but ultimately not chosen for implementation because they were unlikely to reduce impacts to marine mammals or implementation was considered unacceptable with regard to personal safety, practicality of implementation, and impact on effectiveness of the military readiness activity. Separately, as mentioned previously, live MISSILEX exercises were eliminated from the Navy's proposed activities covered under this Final Rule and, therefore, the associated mitigation measures for live MISSILEX exercises that were included in the proposed rule have been removed from the Final Rule. In addition, further details were added to one of the mitigation zones regarding close approaches to marine mammals by vessels to clarify when it is applicable. Below are the mitigation measures as agreed upon by the Navy and NMFS. For additional details regarding the Navy's mitigation measures, see the “Proposed Mitigation” section of the proposed rule (81 FR 9950, 9978-86; February 26, 2016) and Chapter 5 in the GOA FSEIS/OEIS. Lookouts The Navy shall have two types of Lookouts for the purposes of conducting visual observations: Those positioned on ships; and those positioned ashore, in aircraft, or on small boats. Lookouts positioned on ships shall diligently observe the air and surface of the water. They shall have multiple observation objectives, which include but are not limited to detecting the presence of biological resources and recreational or fishing boats, observing the mitigation zones, and monitoring for vessel and personnel safety concerns. Due to manning and space restrictions on aircraft, small boats, and some Navy ships, Lookouts for these platforms may be supplemented by the aircraft crew or pilot, boat crew, range site personnel, or shore-side personnel. Lookouts positioned in minimally manned platforms may be responsible for tasks in addition to observing the air or surface of the water ( e.g., navigation of a helicopter or small boat). However, all Lookouts shall, considering personnel safety, practicality of implementation, and impact on the effectiveness of the activity, comply with the observation objectives described above for Lookouts positioned on ships. The procedural measures described in the remainder of this section primarily consist of having Lookouts during specific training activities. All personnel standing watch on the bridge, Commanding Officers, Executive Officers, maritime patrol aircraft aircrews, anti-submarine warfare helicopter crews, civilian equivalents, and Lookouts shall successfully complete the United States Navy Marine Species Awareness Training prior to standing watch or serving as a Lookout. Additional details on the Navy's Marine Species Awareness Training can be found in the GOA FSEIS/OEIS. The Navy shall use one or more Lookouts during the training activities described below, which are organized by stressor category. Non-Impulsive Sound Hull Mounted Mid-Frequency Active Sonar (MFAS) The Navy's previous Lookout mitigation measures during training activities involving hull-mounted MFAS in the GOA TMAA included requirements such as the number of personnel on watch and the manner in which personnel are to visually search the area in the vicinity of the ongoing activity. The Navy shall maintain the number of Lookouts required by the Phase I incidental take rule and LOA for the GOA TMAA for ships using hull-mounted MFAS. Ships using hull-mounted MFAS sources associated with ASW activities at sea (with the exception of ships less than 65 ft (20 m) in length, which are minimally manned) will have two Lookouts at the forward position. While using hull-mounted MFAS sources underway, vessels less than 65 ft (20 m) in length and ships that are minimally manned shall have one Lookout at the forward position due to space and manning restrictions. High-Frequency and Non-Hull-Mounted Mid-Frequency Active Sonar The Navy plans to conduct activities using high-frequency and non-hull-mounted MFAS in the Study Area. Non-hull-mounted MFAS training activities include the use of aircraft deployed sonobuoys, helicopter dipping sonar, and submarine sonar. During those activities, the Navy shall employ the following mitigation measures regarding Lookout procedures: • Navy aircraft participating in exercises at sea shall conduct and maintain, when operationally feasible and safe, surveillance for marine species of concern as long as it does not violate safety constraints or interfere with the accomplishment of primary operational duties. • Helicopters shall observe/survey the vicinity of an ASW training event for 10 minutes before the first deployment of active (dipping) sonar in the water. The Navy shall continue to use the number of Lookouts (one) required by the Phase I incidental take rule and LOA for the GOA TMAA for ships or aircraft conducting non-hull-mounted MFA sonar activities. The Phase I incidental take rule and LOA for the GOA TMAA did not include mitigation measures for other high-frequency active sonar activities associated with ASW, or for new platforms; therefore, the Navy shall add a new Lookout and other measures for these activities and on these platforms when conducted in the Study Area. The measure is: The Navy shall have one Lookout on ships conducting high-frequency or non-hull mounted mid-frequency active sonar activities associated with ASW activities at sea. Explosives and Impulsive Sound Improved Extended Echo Ranging Sonobuoys The Navy is not proposing use of Improved Extended Echo Ranging Sonobuoys during the GOA TMAA training activities. Explosive Signal Underwater Sound Buoys Using >0.5-2.5 Pound Net Explosive Weight The previous, and first, incidental take rule and LOA (Phase I) for the GOA TMAA did not include lookout measures for explosive signal underwater sound (SUS) buoy activities using >0.5-2.5 pound (lb.) NEW. The Navy shall add this measure. Aircraft conducting SUS activities using >0.5-2.5 lb. NEW will have one Lookout. Gunnery Exercises—Small-, Medium-, and Large-Caliber Using a Surface Target The following Lookout procedures during gunnery exercises are included: • From the intended firing position, trained Lookouts shall survey the mitigation zone for marine mammals prior to commencement and during the exercise as long as practicable. • Target towing vessels shall maintain a Lookout. If a marine mammal is sighted in the vicinity of the exercise, the tow vessel shall immediately notify the firing vessel in order to secure gunnery firing until the area is clear. The Navy shall continue using these Lookout procedures previously implemented for this activity. The Navy shall have one Lookout on the vessel or aircraft conducting small-, medium-, or large-caliber gunnery exercises against a surface target. Towing vessels shall also maintain one Lookout. Missile Exercises Using a Surface Target The following Lookout procedures during missile exercises are included: • Aircraft shall visually survey the target area for marine mammals. Visual inspection of the target area shall be made by flying at 1,500 ft (457 m) or lower, if safe to do so, and at slowest safe speed. • Firing or range clearance aircraft must be able to actually see ordnance impact areas. The Navy shall continue using the Lookout procedures previously implemented for this activity. When aircraft are conducting missile exercises against a surface target, the Navy shall have one Lookout positioned in an aircraft. Bombing Exercises (Explosive) The following Lookout procedures during bombing exercises are included: • If surface vessels are involved, Lookouts shall survey for floating kelp and marine mammals. • Aircraft shall visually survey the target and mitigation zone for marine mammals prior to and during the exercise. The survey of the impact area shall be made by flying at 1,500 ft (460 m) or lower, if safe to do so, and at the slowest safe speed. Release of ordnance through cloud cover is prohibited: aircraft must be able to actually see ordnance impact areas. Survey aircraft should employ most effective search tactics and capabilities. The Navy shall continue implementing these measures for bombing exercises, and shall have one Lookout positioned in an aircraft conducting bombing exercises, and trained Lookouts in any surface vessels involved. Weapons Firing Noise During Gunnery Exercises The Navy shall continue using the number of Lookouts previously required by the Phase I GOA incidental take rule and LOA for gunnery exercises. The Navy shall have one Lookout on the ship conducting explosive and non-explosive gunnery exercises. This may be the same Lookout described for Gunnery Exercises—Small-, Medium-, and Large-Caliber Using a Surface Target when that activity is conducted from a ship against a surface target. Physical Disturbance and Strike Vessels The Navy shall employ the following Lookout procedures to avoid physical disturbance and strike of marine mammals during at-sea training: • While underway, surface vessels shall have at least one Lookout with binoculars, and surfaced submarines shall have at least one Lookout with binoculars. Lookouts already posted for safety of navigation and man-overboard precautions may be used to fill this requirement. As part of their regular duties, Lookouts will watch for and report to the Officer of the Deck the presence of marine mammals. Non-Explosive Practice Munitions Gunnery Exercises—Small-, Medium-, and Large-Caliber Using a Surface Target The Navy employs the same mitigation measures for non-explosive practice munitions—small-, medium-, and large-caliber gunnery exercises—as described above for Gunnery Exercises—Small-, Medium-, and Large-Caliber Using a Surface Target. The Navy shall continue using the number of Lookouts previously implemented for these activities pursuant to the Phase I incidental take rule and LOA for the GOA TMAA. The Navy shall have one Lookout during activities involving non-explosive practice munitions ( e.g., small-, medium-, and large-caliber gunnery exercises) against a surface target. Missile Exercises Using a Surface Target No MISSILEX using live ordnance will be conducted in GOA. When aircraft are conducting non-explosive missile exercises (including exercises using rockets) against a surface target, the Navy shall have one Lookout positioned in an aircraft. Bombing Exercises (Non-explosive) The Navy employs the same mitigation measures for non-explosive bombing exercises as described for Bombing Exercises (Explosive). The Navy shall continue using the same Lookout procedures previously implemented for these activities pursuant to the Phase I incidental take rule and LOA for the GOA TMAA. The Navy will have one Lookout positioned in an aircraft during non-explosive bombing exercises, and trained Lookouts in any surface vessels involved. Mitigation Zones The Navy shall use mitigation zones to reduce the potential impacts to marine mammals from training activities. Mitigation zones are measured as the radius from a source. Unique to each activity category, each radius represents a distance that the Navy will visually observe to help reduce injury to marine species. Visual detections of applicable marine species will be communicated immediately to the appropriate watch station for information dissemination and appropriate action. If the presence of marine mammals is detected acoustically, Lookouts posted in aircraft and on surface vessels will increase the vigilance of their visual surveillance. As a reference, aerial surveys are typically made by flying at 1,500 ft (457 m) altitude or lower at the slowest safe speed. Many of the proposed activities have mitigation measures that were implemented during the Navy's Phase I activities in the GOA TMAA as required by previous environmental documents or consultations. Most of the mitigation zones for activities that involve the use of impulsive and non-impulsive sources were originally designed to reduce the potential for onset of TTS. For the GOA FSEIS/OEIS and the LOA application, the Navy updated the acoustic propagation modeling to incorporate updated hearing threshold metrics ( i.e., upper and lower frequency limits), updated density data for marine mammals, and factors such as an animal's likely presence at various depths. An explanation of the acoustic propagation modeling process can be found in the Determination of Acoustic Effects on Marine Mammals for the Gulf of Alaska Training SEIS/OEIS Technical Report (Marine Species Modeling Team, 2015). Additionally, since publication of the proposed rule, the Navy re-evaluated the range to effects in consideration of the acoustic thresholds in NMFS' new Guidance, which resulted in larger ranges for some explosive sources. As a result of the updates described above, in some cases the ranges to onset of TTS effects are much larger than previous model outputs ( i.e., those used in the first GOA rule (76 FR 25480; May 4, 2011)). Due to the ineffectiveness and unacceptable operational impacts associated with enlarging the mitigation zones to alleviate impacts in these larger areas, the Navy is unable to mitigate for onset of TTS for every activity. For this GOA TMAA analysis, the Navy developed each recommended mitigation zone to avoid or reduce the potential for onset PTS, out to the predicted maximum range. In some cases, where the ranges to effects are smaller than previous models estimated, the mitigation zones were adjusted accordingly to provide consistency across the measures. Mitigating to the predicted maximum range to PTS consequently also mitigates to the predicted maximum range to onset mortality (1 percent mortality), onset slight lung injury, and onset slight gastrointestinal tract injury, since the maximum range to effects for these criteria are shorter than for PTS. Furthermore, in most cases, the predicted maximum range to PTS also consequently covers the predicted average range to TTS. Table 6 summarizes the predicted average range to TTS, average range to PTS, maximum range to PTS, and recommended mitigation zone for each activity category, based on the Navy's acoustic propagation modeling results and updated by consideration of the new acoustic guidance. The activity-specific mitigation zones are based on the longest range for all the functional hearing groups. The mitigation zone for a majority of activities is driven by either the high-frequency cetaceans or the sea turtles functional hearing groups. Therefore, the mitigation zones are even more protective for the remaining functional hearing groups ( i.e., low-frequency cetaceans, mid-frequency cetaceans, and pinnipeds), and likely cover a larger portion of the potential range to onset of TTS. Table 6 includes explosive ranges to TTS and the onset of auditory injury, non-auditory injury, slight lung injury, and mortality. For every source but one proposed for use by the Navy, the mitigation zones included in Table 6 exceed each of these ranges. The TTS range for BOMBEX is larger than the mitigation zone. The mitigation zones and their associated assessments are provided throughout the remainder of this section. Table 6—Predicted Ranges to Effects and Recommended Mitigation Zones for Each Activity Category Activity category Representative source (Bin) 1 Predicted (longest) average range to TTS Predicted (longest) average range to PTS Predicted maximum range to PTS Mitigation zone 2 Non-Impulse Sound Hull-Mounted Mid-Frequency Active Sonar SQS-53 ASW hull-mounted sonar (MF1) 3,821 yd. (3,493 m) for one ping 100 yd. (91 m) for one ping Not applicable 6 dB power down at 1,000 yd. (914 m); 4 dB power down at 500 yd. (457 m); and shutdown at 200 yd. (183 m). High-Frequency and Non-Hull Mounted Mid-Frequency Active Sonar AQS-22 ASW dipping sonar (MF4) 230 yd. (210 m) for one ping 20 yd. (18 m) for one ping Not applicable 200 yd. (183 m). Explosive and Impulse Sound Signal Underwater Sound (SUS) buoys using >0.5-2.5 lb. NEW Explosive sonobuoy (E3) 290 yd. (265 m) 113 yd. (103 m) 309 yd. (283 m) 350 yd. (320 m). Gunnery Exercises—Small- and Medium-Caliber (Surface Target) 40 mm projectiles (E2) 190 yd. (174 m) 83 yd. (76 m) 182 yd. (167 m) 200 yd. (183 m). Gunnery Exercises—Large-Caliber (Surface Target) 3 5 in. projectiles (E5) 771 yd. (705 m) 327 yd. (299 m) 327 yd. (299 m) 600 yd. (549 m). Bombing Exercises 4 MK-84 2,000 lb. (E12) 5,430 yd. (4,965 m) 1,772 yd. (1,620 m) 1,851 yd. (1,693 m) 2,500 yd. (2,286 m). 1 This table does not provide an inclusive list of all sources in a given bins; bins presented here represent the source bin with the largest range to effects within the given activity category. 2 Recommended mitigation zones are larger than the modeled injury zones to account for multiple types of sources or charges being used. See Section 5.3.2 of the GOA FSEIS/OEIS and Section 11.2 of the LOA application (Mitigation Zone Procedural Measures) for a general discussion of mitigation zones, how they are implemented, and the potential effects they are designed to reduce; see Chapter 11 of the LOA application for a discussion of the biological effectiveness and operational assessments for each activity's recommended mitigation zone. 3 Bin E5 TTS Value corrected from Proposed Rule table to reflect correct GOA-specific value for average TTS (Table 3.8-18 of the GOA FSEIS/OEIS). PTS re-assessed using NOAA's August 2016 revised explosive acoustic criteria applicable to the most sensitive functional hearing group. PTS value for bin E5 was lower than previously modeled range, so TTS not recalculated and TTS value from previous model shown as conservative (over predictive) value. Lower weight bins re-assessed similarly did not result in any values larger than existing values shown. 4 Bin E12 PTS and TTS re-assessed using NOAA's August 2016 revised explosive acoustic criteria applicable to the most sensitive functional hearing group. Notes: lb. = pounds, m = meters, yd. = yards; PTS = Permanent Threshold Shift, TTS = Temporary Threshold Shift. For some activities specified throughout the remainder of this section, Lookouts may be required to observe for concentrations of detached floating vegetation (Sargassum or kelp paddies), which are indicators of potential marine mammal presence within the mitigation zone. Those specified activities will not commence if floating vegetation (Sargassum or kelp paddies) is observed within the mitigation zone prior to the initial start of the activity. If floating vegetation is observed prior to the initial start of the activity, the activity will be relocated to an area where no floating vegetation is observed. Training will not cease as a result of floating vegetation entering the mitigation zone after activities have commenced. This measure is intended only for floating vegetation detached from the seafloor. Non-Impulsive Sound Hull-Mounted Mid-Frequency Active Sonar Activities that involve the use of hull-mounted MFA sonar will use Lookouts for visual observation from a ship immediately before and during the activity. Mitigation zones for these activities involve powering down the sonar by 6 dB when a marine mammal is sighted within 1,000 yd (914 m) of the sonar dome, and by an additional 4 dB when sighted within 500 yd (457 m) from the source, for a total reduction of 10 dB. Active transmissions will cease if a marine mammal is sighted within 200 yd (183 m). Active transmission will recommence if any one of the following conditions is met: (1) The animal is observed exiting the mitigation zone, (2) the animal is thought to have exited the mitigation zone based on its course and speed, (3) the mitigation zone has been clear from any additional sightings for a period of 30 minutes, (4) the ship has transited more than 2,000 yd (1.8 km) beyond the location of the last sighting, or (5) the ship concludes that dolphins are deliberately closing in on the ship to ride the ship's bow wave (and there are no other marine mammal sightings within the mitigation zone). Active transmission may resume when dolphins are bow riding because they are out of the main transmission axis of the active sonar while in the shallow-wave area of the ship bow. High-Frequency and Non-Hull-Mounted Mid-Frequency Active Sonar Mitigation will include visual observation from a vessel or aircraft (with the exception of platforms operating at high altitudes) immediately before and during active transmission within a mitigation zone of 200 yd (183 m) from the active sonar source. For activities involving helicopter deployed dipping sonar, visual observation will commence 10 minutes before the first deployment of active dipping sonar. Helicopter dipping and sonobuoy deployment will not begin if concentrations of floating vegetation (kelp paddies), are observed in the mitigation zone. If the source can be turned off during the activity, active transmission will cease if a marine mammal is sighted within the mitigation zone. Active transmission will recommence if any one of the following conditions is met: (1) The animal is observed exiting the mitigation zone, (2) the animal is thought to have exited the mitigation zone based on its course and speed, (3) the mitigation zone has been clear from any additional sightings for a period of 10 minutes for an aircraft-deployed source, (4) the mitigation zone has been clear from any additional sightings for a period of 30 minutes for a vessel-deployed source, (5) the vessel or aircraft has repositioned itself more than 400 yd (370 m) away from the location of the last sighting, or (6) the vessel concludes that dolphins are deliberately closing in to ride the vessel's bow wave (and there are no other marine mammal sightings within the mitigation zone). Explosives and Impulsive Sound Explosive Signal Underwater Sound Buoys Using >0.5-2.5 Pound Net Explosive Weight Mitigation will include pre-exercise aerial monitoring during deployment within a mitigation zone of 350 yd (320 m) around an explosive SUS buoy. Explosive SUS buoys will not be deployed if concentrations of floating vegetation (kelp paddies) are observed in the mitigation zone (around the intended deployment location). SUS deployment will cease if a marine mammal is sighted within the mitigation zone. Deployment will recommence if any one of the following conditions is met: (1) The animal is observed exiting the mitigation zone, (2) the animal is thought to have exited the mitigation zone based on its course and speed, or (3) the mitigation zone has been clear from any additional sightings for a period of 10 minutes. Passive acoustic monitoring will also be conducted with Navy assets, such as sonobuoys, already participating in the activity. These assets would only detect vocalizing marine mammals within the frequency bands monitored by Navy personnel. Passive acoustic detections would not provide range or bearing to detected animals, and therefore cannot provide locations of these animals. Passive acoustic detections would be reported to Lookouts posted in aircraft in order to increase vigilance of their visual surveillance. Gunnery Exercises—Small- and Medium-Caliber Using a Surface Target Mitigation will include visual observation from a vessel or aircraft immediately before and during the exercise within a mitigation zone of 200 yd (183 m) around the intended impact location. Vessels will observe the mitigation zone from the firing position. When aircraft are firing, the aircrew will maintain visual watch of the mitigation zone during the activity. The exercise will not commence if concentrations of floating vegetation (kelp paddies) are observed in the mitigation zone. Firing will cease if a marine mammal is sighted within the mitigation zone. Firing will recommence if any one of the following conditions is met: (1) The animal is observed exiting the mitigation zone, (2) the animal is thought to have exited the mitigation zone based on its course and speed, (3) the mitigation zone has been clear from any additional sightings for a period of 10 minutes for a firing aircraft, (4) the mitigation zone has been clear from any additional sightings for a period of 30 minutes for a firing ship, or (5) the intended target location has been repositioned more than 400 yd (366 m) away from the location of the last sighting. Gunnery Exercises—Large-Caliber Explosive Rounds Using a Surface Target Mitigation will include visual observation from a ship immediately before and during the exercise within a mitigation zone of 600 yd (549 m) around the intended impact location. Ships will observe the mitigation zone from the firing position. The exercise will not commence if concentrations of floating vegetation (kelp paddies) are observed in the mitigation zone. Firing will cease if a marine mammal is sighted within the mitigation zone. Firing will recommence if any one of the following conditions is met: (1) The animal is observed exiting the mitigation zone, (2) the animal is thought to have exited the mitigation zone based on its course and speed, or (3) the mitigation zone has been clear from any additional sightings for a period of 30 minutes. Bombing Exercises (Explosive) During Phase I activities, the Navy employed the following mitigation zone procedures during bombing exercises: • Explosive ordnance shall not be targeted to impact within 2,500 yd (2.3 km) of known or observed floating kelp or marine mammals. • A 2,500 yd (2.3 km) radius mitigation zone shall be established around the intended target. • The exercise will be conducted only if marine mammals are not visible within the mitigation zone. The Navy will (1) maintain the previously required mitigation zone to be used for non-explosive bombing activities, (2) revise the mitigation zone procedures to account for predicted ranges to impacts to marine species when high explosive bombs are used, and (3) add a requirement to visually observe for kelp paddies. Mitigation will include visual observation from the aircraft immediately before the exercise and during target approach within a mitigation zone of 2,500 yd (2.3 km) around the intended impact location for explosive bombs and 1,000 yd (920 m) for non-explosive bombs. The exercise will not commence if concentrations of floating vegetation (kelp paddies) are observed in the mitigation zone. Bombing will cease if a marine mammal is sighted within the mitigation zone. Bombing will recommence if any one of the following conditions is met: (1) The animal is observed exiting the mitigation zone, (2) the animal is thought to have exited the mitigation zone based on its course and speed, or (3) the mitigation zone has been clear from any additional sightings for a period of 10 minutes. Weapons Firing Noise During Gunnery Exercises—Large-Caliber The Navy employed no mitigation zone procedures for this activity in the Study Area during Phase I training activities in the GOA TMAA. For Phase II activities, the Navy will adopt measures currently used during Navy gunnery exercises in other ranges outside of the Study Area. For all explosive and non-explosive large-caliber gunnery exercises conducted from a ship, mitigation will include visual observation immediately before and during the exercise within a mitigation zone of 70 yd (64 m) within 30 degrees on either side of the gun target line on the firing side. The exercise will not commence if concentrations of floating vegetation (kelp paddies) are observed in the mitigation zone. Firing will cease if a marine mammal is sighted within the mitigation zone. Firing will recommence if any one of the following conditions is met: (1) The animal is observed exiting the mitigation zone, (2) the animal is thought to have exited the mitigation zone based on its course and speed, (3) the mitigation zone has been clear from any additional sightings for a period of 30 minutes, or (4) the vessel has repositioned itself more than 140 yd (128 m) away from the location of the last sighting. Physical Disturbance and Strike Vessels The Navy will use a 500 yd (457 m) mitigation zone for whales, and a 200 yd (183 m) mitigation zone for all other marine mammals. Vessels will avoid approaching marine mammals head on and will maneuver to maintain a mitigation zone of 500 yd (457 m) around observed whales and 200 yd (183 m) around all other marine mammals (except bow-riding dolphins), providing it is safe to do so. These requirements will not apply if a vessel's safety is threatened, such as when change of course will create an imminent and serious threat to a person, vessel, or aircraft, and to the extent vessels are restricted in their ability to maneuver. Restricted maneuverability includes, but is not limited to, situations when vessels are engaged in dredging, submerged activities, launching and recovering aircraft or landing craft, minesweeping activities, replenishment while underway, and towing activities that severely restrict a vessel's ability to deviate course. While in transit, Navy vessels shall be alert at all times, use extreme caution, and proceed at a “safe speed” so that the vessel can take proper and effective action to avoid a collision with any sighted object or disturbance, including any marine mammal or sea turtle, and can be stopped within a distance appropriate to the prevailing circumstances and conditions. Towed In-Water Devices The Navy employed no mitigation zone procedures for this activity in the Study Area during Phase I training activities in the GOA TMAA. During Phase II activities in the GOA TMAA, the Navy will adopt measures currently used in other ranges outside of the Study Area during activities involving towed in-water devices. The Navy will ensure that towed in-water devices being towed from manned platforms avoid coming within a mitigation zone of 250 yd (229 m) around any observed marine mammal, providing it is safe to do so. Non-Explosive Practice Munitions Gunnery Exercises—Small-, Medium-, and Large-Caliber Using a Surface Target The Navy will employ the same mitigation measures for non-explosive gunnery exercises as described above for Gunnery Exercises—Small-, Medium-, and Large-Caliber Using a Surface Target. Mitigation will include visual observation from a vessel or aircraft immediately before and during the exercise within a mitigation zone of 200 yd (183 m) around the intended impact location. The exercise will not commence if concentrations of floating vegetation (kelp paddies) are observed in the mitigation zone. Firing will cease if a marine mammal is sighted within the mitigation zone. Firing will recommence if any one of the following conditions is met: (1) The animal is observed exiting the mitigation zone, (2) the animal is thought to have exited the mitigation zone based on its course and speed, (3) the mitigation zone has been clear from any additional sightings for a period of 10 minutes for a firing aircraft, (4) the mitigation zone has been clear from any additional sightings for a period of 30 minutes for a firing ship, or (5) the intended target location has been repositioned more than 400 yd (366 m) away from the location of the last sighting. Bombing Exercises (Non-explosive) Mitigation will include visual observation from the aircraft immediately before the exercise and during target approach within a mitigation zone of 1,000 yd (914 m) around the intended impact location. The exercise will not commence if concentrations of floating vegetation (kelp paddies) are observed in the mitigation zone. Bombing will cease if a marine mammal is sighted within the mitigation zone. Bombing will recommence if any one of the following conditions is met: (1) The animal is observed exiting the mitigation zone, (2) the animal is thought to have exited the mitigation zone based on its course and speed, or (3) the mitigation zone has been clear from any additional sightings for a period of 10 minutes. Consideration of Time/Area Limitations Biologically Important Areas The Navy's and NMFS' analysis of effects to marine mammals considers the best available science regarding locations where cetaceans are known to engage in specific activities ( e.g., feeding, breeding/calving, or migration) at certain times of the year that are important to individual animals as well as populations of marine mammals or where small resident populations may be found (see discussion in Van Parijs, 2015). Where data were available, Van Parijs (2015) identified areas that are important in this way and named the areas Biologically Important Areas (BIAs). It is important to note that the BIAs were not meant to define exclusionary zones, nor were they meant to be locations that serve as sanctuaries from human activity, or areas analogous to marine protected areas (see Ferguson et al. (2015a) regarding the envisioned purpose for the BIA designations). NMFS' recognition of an area as biologically important for some species activity is not equivalent to designation of critical habitat under the Endangered Species Act (ESA). Furthermore, the BIAs identified by NMFS in and around the Study Area do not represent the totality of important habitat throughout the marine mammals' full range. The delineation of BIAs does not have direct or immediate regulatory consequences, although it is appropriate to consider them as part of the body of science that may inform mitigation decisions, depending on the circumstances. The intention was that the BIAs would serve as resource management tools and that they be considered along with, and not to the exclusion of, “existing density estimates, range-wide distribution data, information on population trends and life history parameters, known threats to the population, and other relevant information” (Van Parijs, 2015). The Navy and NMFS have supported and will continue to support the Cetacean and Sound Mapping project, including representation on the Cetacean Density and distribution Working Group (CetMap), which informed NMFS' identification of BIAs. The same marine mammal density data present in the Navy's Marine Species Density Database Technical Report (U.S. Department of the Navy, 2014) and used in the analysis for the GOA SEIS/OEIS was used in the development of BIAs. The final products, including the Gulf of Alaska BIAs, from this mapping effort were completed and published in March 2015 (Aquatic Mammals, 2015; Calambokidis et al., 2015; Ferguson et al., 2015a, 2015b; Van Parijs, 2015). 131 BIAs for 24 marine mammal species, stocks, or populations in seven regions within U.S. waters were identified (Ferguson et al., 2015a). BIAs have been identified in the Gulf of Alaska and include migration and feeding areas for gray whale and North Pacific right whale, respectively. Fin whale feeding areas (east, west, and southwest of Kodiak Island) occur to the west of the GOA TMAA and gray whale feeding areas occur both east (Southeast Alaska) and west (Kodiak Island) of the GOA TMAA; however, these feeding areas are located well outside of (>20 nautical miles) the Study Area and beyond the Navy's estimated range to effects for Level A and B harassment. NMFS' Office of Protected Resources routinely considers available information about marine mammal habitat use to inform discussions with applicants regarding potential spatio-temporal limitations on their activities that might help effect the least practicable adverse impact on species or stocks and their habitat. BIAs are useful tools for planning and impact assessments and are being provided to the public via this Web site: www.cetsound.noaa.gov. While these BIAs are useful tools for analysts, any decisions regarding protective measures based on these areas must go through the normal MMPA evaluation process (or any other statutory process that the BIAs are used to inform); the identification of a BIA does not pre-suppose any specific management decision associated with those areas, nor does it have direct or immediate regulatory consequences. NMFS and the Navy have discussed the BIAs listed above, what Navy activities take place in these areas (in the context of what their effects on marine mammals might be or whether additional mitigation is necessary), and what measures could be implemented to reduce impacts in these areas (in the context of their potential to reduce marine mammal species or stock-level impacts and their practicability). An assessment of the potential spatio-temporal and activity overlap of Navy training activities with the Gulf of Alaska BIAs listed above is included below and in Chapter 3.8 of the GOA FSEIS/OEIS. If, through the adaptive management process or otherwise, it becomes apparent that certain other time-area measures are warranted or are practicable, NMFS and Navy will evaluate these measures within the context of the least practicable impact requirement. Spatial and Temporal Overlap with North Pacific Right Whale Feeding Area —The feeding area for North Pacific right whales (see Ferguson et al., 2015b) overlaps slightly with the GOA TMAA's southwestern corner. This feeding area is applicable from June to September so there is temporal overlap with the proposed Navy training but there is minimal spatial overlap between this feeding area and the GOA TMAA (see Figure 3.8-2 of the GOA FSEIS/OEIS). Given their current extremely low population numbers (the North Pacific right whale is one of the most endangered whale species in the world with approximately 31 individuals) and the general lack of sightings in the Gulf of Alaska, the occurrence of right whales in the GOA TMAA is considered rare. North Pacific right whales have not been visually detected in the GOA TMAA since at least the 1960s and there are no current known detections in the portion of the feeding area that overlaps with the GOA TMAA. The Quinn Seamount passive acoustic detections in summer 2013 (Širović et al., 2014) are the only known potential occurrence records of this species in the GOA TMAA in recent years. The Navy's effects analysis predicts the potential for up to only three Level B behavioral takes annually to North Pacific right whales. These takes are reflected in this final rule. This analysis was based on assigning a nominal North Pacific right whale density to the entire GOA TMAA to account for historic and potential future occurrence in all areas of the TMAA both onshelf and offshelf, and not just associated with the feeding area. However, as discussed above, North Pacific right whales have only potentially been detected in a small portion of the GOA TMAA. Therefore, this predicted level of take is highly conservative. Spatial and Temporal Overlap with Gray Whale Migratory Area —The migration area for gray whales, which was bounded by the extent of the continental shelf (as provided in Ferguson et al., 2015b), has slight (approximately 1 percent) overlap with the GOA TMAA at its northernmost corner and western edge (see Ferguson et al., 2015b; See Figure 3.8-4 of the GOA FSEIS/OEIS). However, this migration area is applicable only between March to May (Spring) and November to January (Fall) (Ferguson et al., 2015b). This gray whale migration area would not be applicable during the months when training has historically occurred (June/July) and would have minimal temporal overlap with most of the proposed timeframe (April to October; summer) for Navy training in the GOA TMAA. The Navy's acoustic analysis did not predict any takes of gray whales in the GOA TMAA based on acoustic effects modeling that considered gray whale occurrence and density as well as the types and quantities of Navy training being authorized, and NMFS is not authorizing any takes of this species (see Group and Species-Specific Analysis section later in this final rule). Analysis of Potential Training Overlap with BIAs —The Location of the GOA TMAA affords aircraft from Navy carrier strike groups supporting joint exercises with the Air Force ability to reach inland established Air Force and Army instrumented land ranges where they conduct air to air ground training. The location of the GOA TMAA also allows appropriate distance limitations to support Air Force aircraft reaching the TMAA without needing to refuel to conduct training at sea with the carrier strike group. Therefore, the GOA TMAA as currently sited is dependent on these location-specific factors to satisfy safety and practicality concerns. However, it is unlikely that Navy training using hull-mounted mid-frequency active sonar or explosives training would occur in these nearshore locations adjacent to the GOA TMAA boundary where the overlap with BIAs occurs. To ensure that the Navy is able to conduct realistic training, Navy units must maintain sufficient room to maneuver. Therefore, training activities using sonar and explosives will typically take place some distance away from an operating area boundary to ensure sufficient sea or air space is available for tactical maneuvers within an approved operating area such as the GOA TMAA. The Navy also does not typically train next to any limiting boundary of the GOA TMAA because it precludes tactical consideration of the adjacent sea space and airspace beyond the boundary from being a potential threat axis during activities such as anti-submarine warfare training. It is also the case that Navy training activities will generally not be located where it is likely there would be interference from civilian vessels and aircraft that are not participating in the training activity. The nearshore boundary of the GOA TMAA is the location for multiple commercial vessel transit lanes, ship traffic, and low-altitude air routes, which all pass through the feeding area and the migration area (see Figure 3.8-9 of the GOA FSEIS/OEIS). This level of civilian activity may otherwise conflict with Navy training activities if those Navy activities were located at that margin of the GOA TMAA and as a result such an area is generally avoided. There are northeastern and northwestern areas of the GOA TMAA, portions of which overlap the BIAs, that could be used for other non-acoustic and non-explosive Navy training events, including vessel movements. As detailed in the GOA FSEIS/OEIS, these could include up to 24 Visit, Board, Search, and Seizure training activities and 28 Maritime Interdiction training activities which often interact with participating contracted commercial vessels homeported out Gulf of Alaska ports ( e.g., Kodiak, Homer, etc.). Conclusion for North Pacific Right Whale BIA —After evaluating the potential training overlap with the North Pacific right whale BIA and the activities expected to result in the take of this species, the endangered status of the species, the extremely small numbers of North Pacific right whales, and the practicability of implementation, NMFS is requiring—and Navy has agreed to—a North Pacific right whale “Cautionary Area” between June and September in the overlapping 2,051 km 2 portion of the North Pacific right whale feeding area (See Figure 3.8-4 of the GOA FSEIS/OEIS), in which the Navy would agree no hull-mounted sonar or explosives would be used within the portion of the feeding area that overlaps the Navy's GOA TMAA during those months. In the event of national security needs, the Navy would be required to seek approval in advance from the Commander, U.S. Third Fleet prior to conducting training activities using sonar or explosives. NMFS believes that implementation of this North Pacific right whale Cautionary Area within the GOA TMAA may provide additional protection of this species and stock beyond the mitigation measures already proposed by the Navy in the proposed rule and GOA FSEIS/OEIS, especially when factoring in their small population size, the status and abundance of the stock (well below its Optimum Sustainable Population (Muto et al., 2016)), and the extremely limited current information about this species. NMFS believes that this additional mitigation measure may contribute to reducing the number of individual North Pacific right whales taken through exposure to MFAS/HFAS or underwater detonations in an area/time that is important for feeding, which could contribute to a reduction in the probability or severity of adverse impacts on the species or stock or their habitat. Conclusion for Gray Whale BIA —In the case of the gray whale migratory area, given the extremely minimal geographic and temporal overlap with Navy training activities in the GOA TMAA, coupled with the fact that no takes of gray whale are predicted to occur with the proposed level of training effort, NMFS has determined that additional mitigation measures related to time/area limitations of Navy training activities within the overlapping portion of the migratory area would not contribute to any lessening of the likelihood of adverse impacts on the species or stocks or their habitat, and are therefore not warranted in the context of the least practicable impact standard. Marine Protected Areas Marine protected areas (MPAs) in the National System of MPAs potentially occurring within the Study Area are listed and described in Section 6.1.2 of the GOA FSEIS/OEIS (Marine Protected Areas, Table 6.1-2). As shown in Figure 6.1-1 of the GOA FSEIS/OEIS very few MPA are located within the GOA TMAA. MPAs vary widely in purpose, level of protection, and restrictions on human uses. As discussed in the GOA FSEIS/OEIS, MPAs in the vicinity of the GOA TMAA generally focus on natural heritage, fishery management, and sustainable production. The GOA FSEIS/OEIS has been prepared in accordance with the requirements to avoid harm to the natural and cultural resources of existing National System MPAs. The identified impacts and purpose for the designation of these areas is to limit or restrict specific fishing activities. Navy activities, should they occur within or near a MPA, would fully abide by the regulations of the individual MPA, including designated fishery management habitat protection areas, and relevant resources (in the case of the GOA TMAA, mainly restrictions on commercial and recreational fishing) (see Table 6.1-2 of the GOA FSEIS/OEIS for more information). Further, NMFS' issuance of an authorization to the Navy to take marine mammals would not conflict with the management, protection, or conservation objectives of these MPAs. Therefore, NMFS has determined that Navy avoidance of these areas is not warranted, nor would it contribute to the least practicable impact standard or any lessening of the likelihood of adverse impacts on species or stocks or their habitat. Seamounts As with previous Navy Phase II proposed rulemakings, commenters have requested that the Navy avoid training activities in the vicinity of seamounts or seamount chains, which represent potentially important habitat for marine species. Numerous seamounts are located partially or wholly within the TMAA, including seamount habitat protection areas designated by the North Pacific Fishery Management Council to help maintain productivity of fishery resources. However, NMFS does not believe that Navy avoidance of these areas is warranted, or will contribute to the least practicable impact standard or any lessening of the likelihood of adverse impacts on marine mammal species or stocks for the following reasons: If marine mammals are known to prefer certain types of areas (as opposed to specific areas) for certain functions, such as beaked whale use of seamounts or marine mammal use of other productive areas, it is less effective to require avoidance or limited use of a specific area because marine mammals may or may not be present. NMFS recognizes the generally biologically productive nature of seamounts; however, there are no data to suggest that biologically important or species-specific marine mammal habitat (rookeries, reproductive, feeding) exists along seamounts within the GOA TMAA. While seamounts may represent important habitat for multiple species, the major seamounts located within the TMAA ( e.g., Dall, Quinn, and Giacomini seamounts) have been designated by NOAA as Gulf of Alaska Seamount Habitat Protection Areas specifically to help maintain productivity of fisheries resources through restrictions on bottom fishing. Moreover, NMFS' review of the passive acoustic monitoring results in the Navy's annual monitoring reports (2011-2015, available at the Navy's Marine Species Monitoring web portal ( http://www.navymarinespeciesmonitoring.us/ )) for GOA generally does not suggest significantly greater use of these seamounts by marine mammals (at least for those where high-frequency acoustic recording packages (HARPs) were deployed; it is also important to note that an animal may be located several miles away from where it is detected) compared to other locations (shelf and slope) where detections were recorded. Navy monitoring efforts indicate that beaked whales appear to use both shelf and seamount sites, although detections were generally low at the monitored seamount sites within the TMAA and may be more prevalent at the slope site. During a summer 2013 visual and passive acoustic survey of the entire GOA TMAA, beaked whale passive acoustic detections were just as frequent over deep water abyssal plain areas of the TMAA as compared to slopes and seamounts (Rone et al., 2014). Fin and humpback callings peaked in winter when Navy activities are not proposed to occur. Fin and sperm whale detections were generally more prevalent at shelf and slope sites, respectively, while blue whale calls were detected at all sites. North Pacific right whale calls were last detected in 2013, on the Quinn Seamount site; however, analysis of these detections indicated that the calls were detected from ranges on the order of roughly up to 50 nm to the east of the site; the calling animal was not in the vicinity of Quinn Seamount (Debich et al., 2014; Širović et al., 2014). The Navy has been training with sonar and other systems for decades in locations having seamounts or slope areas, or that are adjacent to continental shelfs where, to date, there has been no evidence of any long-term consequences for individuals or populations of marine mammals generally or around seamounts. This finding is based on years of research and monitoring that show, for example, higher densities and long-term residency by species such as beaked whales in Southern California, where the Navy trains and tests, than in other adjacent areas (Falcone et al., 2009; Falcone and Schorr, 2012, 2014; Hildebrand and McDonald, 2009). Further, the Navy has identified the need to train in varied bathymetric conditions, including around seamounts specifically, to afford realistic training. Restricting Navy maneuvering or sonar/explosives training in these areas would alter realistic training to a degree that could impede ability to have sufficient sea or air space for the necessary tactical maneuvers. When the impact on the effectiveness of the training is considered along with the facts described above ( i.e., the fact that Navy monitoring has not indicated a strong preference for the GOA TMAA seamounts by marine mammal species, indicating only limited potential to reduce impacts to marine mammal species or stocks and their habitat), we determined that avoidance of seamounts in the GOA TMAA is not warranted in this particular circumstance. Stranding Response Plan NMFS and the Navy developed a Stranding Response Plan for GOA TMAA in 2011 as part of the previous (2011-2016) MMPA authorization and rulemaking process for the Study Area. The Stranding Response Plan is specifically intended to outline the applicable requirements in the event that a marine mammal stranding is reported in the complexes during a major training exercise. NMFS considers all plausible causes within the course of a stranding investigation and this plan in no way presumes that any strandings are related to, or caused by, Navy training activities, absent a determination made during investigation. The plan is designed to address mitigation, monitoring, and compliance. NMFS has updated the Stranding Response Plan for the GOA TMAA for 2017-2022 training activities. The updated Stranding Response Plan can be found at: http://www.nmfs.noaa.gov/pr/permits/incidental/military.htm#navy_goa2021. In addition, modifications to the Stranding Response Plan may also be made through the adaptive management process. Mitigation Conclusions NMFS has carefully evaluated the Navy's proposed mitigation measures—many of which were developed with NMFS' input during the first phase of incidental take authorizations for the Navy's training activities—and considered a broad range of other measures in the context of ensuring that NMFS prescribes the means of effecting the least practicable adverse impact on the affected marine mammal species and stocks and their habitat. Our evaluation of potential measures included the manner in which, and the degree to which, the successful implementation of the measure(s) is expected to reduce impacts to marine mammals, marine mammal species or stocks, their habitat, and their availability for subsistence uses (where relevant). Among other things, this analysis considered the nature of the potential adverse impact (likelihood, scope, range), the likelihood that a measure would be effective if implemented, and the likelihood of effective successful implementation. Our evaluation of potential measures also considered the practicability of the measures for applicant implementation. Practicability of implementation includes consideration of such things as cost, impact on operations, and, in the case of a military readiness activity, personnel safety, practicality of implementation, and impact on the effectiveness of the military readiness activity. Based on our evaluation of the Navy's proposed measures, as well as other measures considered by NMFS, NMFS has determined that the mitigation measures required by this rule are adequate means of effecting the least practicable adverse impacts on marine mammals species or stocks and their habitat, paying particular attention to rookeries, mating grounds, and areas of similar significance, while also considering personnel safety, practicality of implementation, and impact on the effectiveness of the military readiness activity. Monitoring Se [Text truncated at 120,000 characters. The full text is on the page linked above.] --- Source: Frix Law Library, https://www.frixlaw.com/law-library/documents/fr%3A2017-08424. Public record. Not legal advice.