Source: https://www.federalregister.gov/documents/2009/07/14/E9-16537/taking-of-marine-mammals-incidental-to-specified-activities-taking-marine-mammals-incidental-to
Timestamp: 2018-07-23 08:44:00
Document Index: 597185968

Matched Legal Cases: ['§\u2009216', '§\u2009218', '§\u2009218', '§\u2009218', '§\u2009218', '§\u2009218', '§\u2009218', '§\u2009218', '§\u2009216', '§\u2009218', '§\u2009218', '§\u2009218', '§\u2009218', '§\u2009216', '§\u2009216', '§\u2009218', '§\u2009218', '§\u2009216', '§\u2009218']

Comments and information must be received no later than August 13, 2009.
33960-33986 (27 pages)
(A) Bombing Exercise (Air-to-Surface) [BOMEX (A-S)]
(B) Small Arms Training (Explosive Hand Grenades)
Model-Derived Density Estimates—Line Transect Survey Data
Stock Assessment Report or Literature-Derived Density Estimates
I. Level B Harassment
II. Level A Harassment
III. Acoustic Environment
IV. Acoustic Effects Analysis
1. BOMBEX
2. Small Arms Training
3. Summary of Potential Exposures From Explosive Ordnance Use
I. Small Arms Training—Explosive Hand Grenades (MK3A2 Grenades)
II. Air-to-Surface At-Sea Bombing Exercises (BOMBEX, 500-lb to 2,000-lb Explosive Bombs)
Proposed Monitoring Plan for the GOMEX Range Complex
Subpart D—Taking Marine Mammals Incidental to U.S. Navy Training in the Gulf of Mexico Range Complex (GOMEX Range Complex)
https://www.federalregister.gov/d/E9-16537 https://www.federalregister.gov/d/E9-16537
You may submit comments, identified by 0648-AX86, by any one of the following methods:
NMFS will accept anonymous comments (enter NA in the required Start Printed Page 33961fields if you wish to remain anonymous). Attachments to electronic comments will be accepted in Microsoft Word, Excel, WordPerfect, or Adobe PDF file formats only.
A copy of the Navy's application may be obtained by writing to the address specified above (See ADDRESSES), telephoning the contact listed above (see FOR FURTHER INFORMATION CONTACT), or visiting the Internet at: http://www.nmfs.noaa.gov/​pr/​permits/​incidental.htm#applications. The Navy's Draft Environmental Impact Statement (DEIS) for the GOMEX Range Complex was published in November 2008, and may be viewed at http://www.gomexrangecomplexeis.com/​. NMFS participated in the development of the Navy's DEIS as a cooperating agency under the National Environmental Policy Act (NEPA).
On October 2, 2008, NMFS received an application from the Navy requesting an authorization for the take of marine mammal species/stocks incidental to the proposed training operations within the GOMEX Range Complex over the course of 5 years. These training activities are classified as military readiness activities. The Navy states that these training activities may cause various impacts to marine mammal species in the proposed GOMEX Range Complex Study Area. The Navy requests an authorization to take 8 species of cetaceans annually by Level B harassment, and 1 individual each of pantropical spotted dolphin and spinner dolphin by Level A harassment (injury). Please refer to the take table on page 6-17 of the LOA application for detailed information of the potential exposures from explosive ordnance (per year) for marine mammals in the GOMEX Range Complex. However, due to the implementation of the proposed mitigation and monitoring measures, NMFS believes that the actual take would be less than estimated.
The GOMEX Study Area encompasses areas at sea, undersea, and Special Use Airspace (SUA) in the northern Gulf of Mexico off the coast of the U.S. (Figures 1 and 2 of the LOA application). The portions of the GOMEX Study Area to be considered for the proposed action consist of the BOMBEX Hotbox (surface and subsurface waters) located within the Pensacola Operation Area (OPAREA), SUA warning areas W-151A/B/C and W-155A/B (surface waters), and underwater detonation (UNDET) Area E3 (surface and subsurface waters), located within the territorial waters off Padre Island, Texas, near Corpus Christi NAS. The portions of the GOMEX Study Area addressed in the Navy's LOA application encompass:
11,714 nm2 (40,178 km2) of SUA warning areas (vessel movements only) The BOMBEX Hotbox is an in-water operating and maneuvers area with defined air, ocean surface, and subsurface areas. The BOMBEX Hotbox is located in the offshore waters of the northeastern Gulf of Mexico (GOM) adjacent to Florida and Alabama. The northernmost boundary of the BOMBEX Hotbox is located 23 nm (42.6 km) from the coast of the Florida panhandle at latitude 30 °N, the eastern boundary is approximately 200 nm (370.4 km) from the coast of the Florida peninsula at longitude 86°48′ W.
The UNDET Area E3 is a defined surface and subsurface area located in the waters south of Corpus Christi NAS and offshore of Padre Island, Texas. The westernmost boundary is located 7.5 nm (13.9 km) from the coast of Padre Island at 97°9′33″ W and 27°24′26″ N at the Western most corner. It lies entirely within the territorial waters (0 to 12 nm, or 0 to 22.2 km) of the U.S. and the majority of it lies within Texas state waters (0 to 9 nm, or 0 to 16.7 km). It is a very shallow water training area with depths ranging from 20 to 26 m.
In the application submitted to NMFS, the Navy requests an authorization to take marine mammals incidental to conducting training operations within the GOMEX Range Complex. These training activities consist of surface warfare. Although vessel movement is also a component of the proposed GOMEX Range Complex training activities, the Navy concludes that it is unlikely marine mammals would be taken by vessel movement with the implementation of mitigation and monitoring measures described in the Mitigation Measures and Monitoring Measures sections.
Surface Warfare (SUW) supports defense of a geographical area (e.g., a zone or barrier) in cooperation with surface, subsurface, and air forces. SUW operations detect, localize, and track surface targets, primarily ships. Detected ships are monitored visually and with radar. Operations include identifying surface contacts, engaging with weapons, disengaging, evasion, and avoiding attack, including implementation of radio silence and deceptive measures. For the proposed GOMEX Range Complex training operations, SUW events involving the use of explosive ordnance include air-to-surface Bombing Exercises [BOMEX (A-S)] and small arms training (involving explosive hand grenades) that occur at sea. Start Printed Page 33962
For the proposed BOMBEX (A-S), two aircraft will approach an at-sea target from an altitude of between 15,000 ft (4,572 m) to less than 3,000 ft (914.4 m) and release a high explosive (HE) 1,000-pound (lb) bomb on the target. MK-83 bombs would be used. MK-83 bombs have a net explosive weight (NEW) of 415.8 lbs. The typical bomb release altitude is below 3,000 ft (914.4 m) and the target is usually a flare. The time in between bomb drops is approximately 3 minutes.
Small arms training is a part of quarterly reservist training and operational activities for the Mobile Expeditionary Security Group (MESG) that operates out of Corpus Christi Naval Air Station (NAS). The MESG trains with MK3A2 (0.5-lb NEW) anti-swimmer concussion grenades. The MK3A2 grenades are small and contain high explosives in an inert metal or plastic shell. They detonate at about 3 m under the water's surface within 4 to 5 seconds of being deployed. The detonation depth may be shallower depending upon the speed of the boat at the time the grenade is deployed.
A number of different types of boats will be used depending on the unit using the boat and their mission. Boats are mostly used by naval special warfare (NSW) teams and Navy Expeditionary Combat Command (NECC) units (Naval Coastal Warfare, Inshore Boat Units, Mobile Security Detachments, Explosive Ordnance Disposal, and Riverine Forces). These units are used to protect ships in harbors and high value units, such as aircraft carriers, nuclear submarines, liquid natural gas tankers, etc., while entering and leaving ports, as well as to conduct riverine operations, insertion and extractions, and various NSW operations.
The boats used by these units include: Small Unit River Craft (SURC), Combat Rubber Raiding Craft (CRRC), Rigid Hull Inflatable Boats (RHIB), Patrol Craft, and many other versions of these types of boats. These boats use inboard or outboard, diesel or gasoline engines with either propeller or water jet propulsion.
This exercise is usually a live-fire exercise with M3A2 Anti-swimmer Concussion Grenades, but at times blanks may be used so boat crews can practice their ship-handling skills for the employment of weapons without being concerned with the safety requirements involved with HE weapons. Boat crews may use high or low speeds to approach and engage targets simulating swimmers with anti-swimmer concussion grenades. The purpose of this exercise is to develop marksmanship skills and small boat ship-handling tactics skills required to employ these weapons. Training usually lasts 1-2 hours. Small arms training in the GOMEX Study Area will occur during day or evening hours in the UNDET Area E3.
Table 1 summarizes the level of Surface Warfare training activities planned in the GOMEX Range Complex for the proposed action.
Bombing Exercise (BOMBEX) (Air-to-Surface, At-Sea) F/A-18 MK-831,000-lb High Explosive (HE) bomb] 415.8 lbs NEW 1 event (4 bombs in succession) BOMBEX Hotbox Daytime only 1 hour.
Small Arms Training Maritime Expeditionary Support Group (Various Small Boats) MK3A2 anti-swimmer grenades (8-oz HE grenade) 0.5 lb NEW 6 events* (20 live grenades) UNDET Area E3 Day or night 1 hour.
* An individual event can include detonation of up to 10 live grenades, but no more than 20 live grenades will be used per year.
Vessel movements are associated with most training and operational activities in the GOMEX Study Area. Currently, the number of Navy vessels operating in the GOMEX Study Area varies based on training schedules and can range from 0 to about 10 vessels at any given time. Vessel sizes range from small boats (<35 ft, or 10.7 m) for a harbor security boat to 1,092 ft (332.8 m) for a CVN (carrier vessel nuclear) and speeds generally range from 10 to 14 knots, but may be considerably faster, for example an aircraft carrier “making wind” while launching and recovering aircraft, and for small boat operations. Operations involving vessel movements occur intermittently and are variable in duration, ranging from a few hours up to 2 weeks. These operations are widely dispersed throughout the GOMEX Study Area, which is an area encompassing 11,714 nm2 (40,178 km2). Most vessel movements occur in the offshore OPAREAs, but vessel movements associated with MESG training in the UNDET Area E3 and Commander Naval Installations Command (CNIC) harbor security group training in the Panama City OPAREA occur between shore and 12 nm (22.2 km), including the nearshore zone (<3 nm, or 5.6 km). The Navy logs about 180 total vessel days within the GOMEX Study Area during a typical year. Consequently, the density of Navy vessels within the GOMEX Study Area at any given time is low (i.e., less than 0.0113 ships/nm2 (0.0386 km2)).
Twenty-nine marine mammal species have confirmed or potential occurrence in the GOMEX Study Area. These include 28 cetacean species and 1 sirenian species (DoN, 2007a), which can be found in Table 2. Although it is possible that any of the 29 species of marine mammals may occur in the Study Area, only 21 of those species are expected to occur regularly in the region. Most cetacean species are in the Study Area year-round (e.g., sperm whales and bottlenose dolphins), while a few (e.g., fin whales and killer whales) have accidental or transient occurrence in the area. Start Printed Page 33963
The information contained in this section relies heavily on the data gathered in the Marine Resources Assessments (MRAs). The Navy MRA Program was implemented by the Commander, Fleet Forces Command, to initiate collection of data and information concerning the protected and commercial marine resources found in the Navy's OPAREAs. Specifically, the goal of the MRA program is to describe and document the marine resources present in each of the Navy's OPAREAs. The MRA for the GOMEX OPAREA was published in 2007 (DoN, 2007a). The MRA data were used to provide a regional context for each species. The MRA represents a compilation and synthesis of available scientific literature (e.g., journals, periodicals, theses, dissertations, project reports, and other technical reports published by government agencies, private businesses, or consulting firms), and NMFS reports including stock assessment reports (SARs), recovery plans, and survey reports. This information was used to evaluate the potential for occurrence of marine mammal species in the GOMEX Study Area.
The density estimates that were used in previous Navy environmental documents have been recently updated to provide a compilation of the most recent data and information on the occurrence, distribution, and density of marine mammals. The updated density estimates presented in this LOA application are derived from the Navy OPAREA Density Estimates (NODEs) for the GOMEX OPAREA report (DoN, 2007b).
The analyses for cetaceans were based on sighting data collected through shipboard surveys conducted by NMFS SEFSC between 1996 and 2004. Species-specific density estimates derived through spatial modeling were compared with abundance estimates found in the 2006 NOAA SARs to ensure consistency. All spatial models and density estimates were reviewed by and coordinated with NMFS Science Start Printed Page 33964Center technical staff and scientists with the University of St. Andrews, Scotland, Centre for Environmental and Ecological Modeling (CREEM). For a more detailed description of the methods involved in calculating the density estimates provided in this LOA request, please refer to the NODE report for the GOMEX OPAREA (DoN, 2007b). The following lists how density estimates were derived for each species:
Sperm whale, dwarf and pygmy sperm whales, beaked whales, rough-toothed dolphin, bottlenose dolphin (Tursiops truncatus), pantropical spotted dolphin, Atlantic spotted dolphin, striped dolphin, spinner dolphin, and Risso's dolphin.
Bryde's whale, Clymene dolphin, Fraser's dolphin, killer whale, false killer whale, pygmy killer whale, melon-headed whale, short-finned pilot whale.
The Navy considers that explosions associated with BOMBEX (A-S) and small arms training are the activities with the potential to result in Level A or Level B harassment of marine mammals. Vessel strikes were also analyzed for potential effect to marine mammals.
Collisions with commercial and Navy ships can result in serious injury and may occasionally cause fatalities to cetaceans and manatees. Although the most vulnerable marine mammals may be assumed to be slow-moving cetaceans or those that spend extended periods of time at the surface in order to restore oxygen levels within their tissues after deep dives (e.g., sperm whale), fin whales are actually struck most frequently (Laist et al., 2001). Manatees are also particularly susceptible to vessel interactions and collisions with watercraft constitute the leading cause of mortality (USFWS, 2007). Smaller marine mammals such as bottlenose and Atlantic spotted dolphins move more quickly throughout the water column and are often seen riding the bow wave of large ships. Marine mammal responses to vessels may include avoidance and changes in dive patterns (NRC, 2003).
In the Gulf of Mexico, sperm whales are of particular concern. Sperm whales spend extended periods of time at the surface in order to restore oxygen levels within their tissues after deep dives. In addition, some baleen whales such as the North Atlantic right whale seem generally unresponsive to vessel sound, making them more susceptible to vessel collisions (Nowacek et al., 2004a). In comparison with other regions of the U.S., the Gulf of Mexico is the least common area for ship strikes of large whales (Jensen and Silber, 2003). Between 1972 and 1999, eight confirmed or possible large whale ship strikes were recorded in the Gulf of Mexico, including two that collided with Navy vessels; four of these resulted in mortality of the animal (Jensen and Silber, 2003) and one resulted in extensive damage to a Navy vessel (Laist et al., 2001). It is not known whether the shipstrikes involving Navy vessels resulted in the mortality of the animal (Laist et al., 2001; Jensen and Silber, 2003).
Accordingly, the Navy has proposed mitigation measures to reduce the potential for collisions with surfaced marine mammals (for more details refer to Proposed Mitigation Measures below). Based on the implementation of Navy mitigation measures and the relatively low density of Navy ships in the Study Area the likelihood that a vessel collision would occur is very low.
Baleen whales: “When baleen whales receive low-level sounds from distant or Start Printed Page 33965stationary vessels, the sounds often seem to be ignored. Some whales approach the sources of these sounds. When vessels approach whales slowly and nonaggressively, whales often exhibit slow and inconspicuous avoidance maneuvers. In response to strong or rapidly changing vessel noise, baleen whales often interrupt their normal behavior and swim rapidly away. Avoidance is especially strong when a boat heads directly toward the whale.”
It is important to recognize that behavioral responses to stimuli are complex and influenced to varying degrees by a number of factors such as species, behavioral contexts, geographical regions, source characteristics (moving or stationary, speed, direction, etc.), prior experience of the animal, and physical status of the animal. For example, studies have shown that beluga whales reacted differently when exposed to vessel noise and traffic. In some cases, naive beluga whales exhibited rapid swimming from ice-breaking vessels up to 80 km away, and showed changes in surfacing, breathing, diving, and group composition in the Canadian high Arctic where vessel traffic is rare (Finley et al., 1990). In other cases, beluga whales were more tolerant of vessels, but differentially responsive by reducing their calling rates, to certain vessels and operating characteristics (especially older animals) in the St. Lawrence River where vessel traffic is common (Blane and Jaakson, 1994). In Bristol Bay, Alaska, beluga whales continued to feed when surrounded by fishing vessels and resisted dispersal even when purposefully harassed (Fish and Vania, 1971).
In the case of the GOMEX Range Complex, naval vessel traffic is expected to be much lower than in areas where there are large shipping lanes and large numbers of fishing vessels and/or recreational vessels. Nevertheless, the proposed action area is well traveled by a variety of commercial and recreational vessels, so marine mammals in the area are expected to be habituated to vessel noise.
As described earlier in this document, operations involving vessel movements occur intermittently and are variable in duration, ranging from a few hours up to 2 weeks. These operations are widely dispersed throughout the GOMEX Range Complex OPAREA, which is a vast area encompassing 11,714 nm2. The Navy logs about 180 total vessel days within the Study Area during a typical year. Consequently, the density of ships within the Study Area at any given time is extremely low (i.e., less than 0.0113 ships/nm2).
Moreover, naval vessels transiting the study area or engaging in the training exercises will not actively or intentionally approach a marine mammal or change speed drastically. All vessels transiting to, from, and within the range complexes will be traveling at speeds generally ranging from 10 to 14 knots. In addition, mitigation measures described below require Navy vessels to keep at least 500 yards (460 m) away from any observed whale and at least 200 yards (183 m) from marine mammals other than whales, and avoid approaching animals head-on. Although the radiated sound from the vessels will be audible to marine mammals over a large distance, it is unlikely that animals will respond behaviorally to low-level distant shipping noise as the animals in the area are likely to be habituated to such noises (Nowacek et al., 2004). In light of these facts, NMFS does not expect the Navy's vessel movements to result in Level B harassment.
Auditory trauma represents direct mechanical injury to hearing related structures, including tympanic membrane rupture, disarticulation of the middle ear ossicles, and trauma to the inner ear structures such as the organ of Corti and the associated hair cells. Auditory trauma is always injurious that could result in PTS and is always assumed to result in a stress response.
Auditory fatigue refers to a loss of hearing sensitivity after sound stimulation. The loss of sensitivity persists after, sometimes long after, the cessation of the sound. The mechanisms responsible for auditory fatigue differ from auditory trauma and would primarily consist of metabolic exhaustion of the hair cells and cochlear tissues. The features of the exposure (e.g., amplitude, frequency, duration, temporal pattern) and the individual animal's susceptibility would determine the severity of fatigue and whether the Start Printed Page 33966effects were temporary (TTS) or permanent (PTS). Auditory fatigue (PTS or TTS) is always assumed to result in a stress response.
If the acoustic source does not produce tissue effects, is not perceived by the animal, or does not produce a stress response by any other means, we assume that the exposure does not contribute to the allostatic load. Additionally, without a stress response or auditory masking, it is assumed that there can be no behavioral change. Conversely, any immediate effect of exposure that produces an injury is assumed to also produce a stress response and contribute to the allostatic load. Start Printed Page 33967
Because the ears are the most sensitive to pressure, they are the organs most sensitive to injury (Ketten, 2000). Sound-related damage associated with blast noise can be theoretically distinct from injury from the shock wave, particularly farther from the explosion. If an animal is able to hear a noise, at some level it can damage its hearing by causing decreased sensitivity (Ketten, 1995) (See Assessment of Marine Mammal Response to Anthropogenic Sound Section above). Sound-related trauma can be lethal or sublethal. Lethal Start Printed Page 33968impacts are those that result in immediate death or serious debilitation in or near an intense source and are not, technically, pure acoustic trauma (Ketten, 1995). Sublethal impacts include hearing loss, which is caused by exposures to perceptible sounds. Severe damage (from the shock wave) to the ears includes tympanic membrane rupture, fracture of the ossicles, damage to the cochlea, hemorrhage, and cerebrospinal fluid leakage into the middle ear. Moderate injury implies partial hearing loss due to tympanic membrane rupture and blood in the middle ear. Permanent hearing loss also can occur when the hair cells are damaged by one very loud event, as well as by prolonged exposure to a loud noise or chronic exposure to noise. The level of impact from blasts depends on both an animal's location and, at outer zones, on its sensitivity to the residual noise (Ketten, 1995).
The exercises that use explosives in this request include BOMBEX (A-S) and GUNEX (S-S). Table 1 summarizes the number of events and specific areas where each occurs for each type of explosive ordnance used. There is no difference in how many events take place between the different seasons. Fractional values are a result of evenly distributing the annual totals over the four seasons. For example, there is one BOXEX event per year that can take place in the BOMBEX Hotbox during any season, so there are 0.25 event modeled for each season.
(A) Behavioral Harassment—Behavioral disturbance that rises to the level described in the definition above, when resulting from exposures to underwater detonations, is considered Level B Harassment. Some of the lower level physiological stress responses discussed in the Assessment of Marine Mammal Response to Anthropogenic Sound section will also likely co-occur with the predicted harassments, although these responses are more difficult to detect and fewer data exist relating these responses to specific received levels of sound. When Level B Harassment is predicted based on estimated behavioral responses, those takes may have a stress-related physiological component as well.
(B) Acoustic Masking and Communication Impairment—Acoustic masking is considered Level B Harassment as it can disrupt natural behavioral patterns by interrupting or limiting the marine mammal's receipt or transmittal of important information or environmental cues.
(C) TTS—As discussed previously, TTS can affect how an animal behaves in response to the environment, including conspecifics, predators, and prey. The following physiological mechanisms are thought to play a role in inducing auditory fatigue: effects to sensory hair cells in the inner ear that reduce their sensitivity, modification of the chemical environment within the sensory cells, residual muscular activity in the middle ear, displacement of certain inner ear membranes, increased blood flow, and post-stimulatory reduction in both efferent and sensory neural output. Ward (1997) suggested that when these effects result in TTS rather than PTS, they are within the normal bounds of physiological variability and tolerance and do not represent a physical injury. Additionally, Southall et al. (2007) indicate that although PTS is a tissue injury, TTS is not because the reduced hearing sensitivity following exposure to intense sound results primarily from fatigue, not loss, of cochlear hair cells and supporting structures and is reversible. Accordingly, NMFS classifies TTS (when resulting from exposure to underwater detonations) as Level B Harassment, not Level A Harassment (injury).
(A) PTS—PTS is irreversible and considered to be an injury. PTS results from exposure to intense sounds that cause a permanent loss of inner or outer cochlear hair cells or exceed the elastic limits of certain tissues and membranes in the middle and inner ears and result in changes in the chemical composition of the inner ear fluids.
(B) Physical Disruption of Tissues Resulting from Explosive Shock Wave—Physical damage of tissues resulting from a shock wave (from an explosive detonation) is classified as an injury. Blast effects are greatest at the gas-liquid interface (Landsberg, 2000) and gas-containing organs, particularly the lungs and gastrointestinal tract, are especially susceptible to damage (Goertner, 1982; Hill 1978; Yelverton et al., 1973). Nasal sacs, larynx, pharynx, trachea, and lungs may be damaged by compression/expansion caused by the oscillations of the blast gas bubble (Reidenberg and Laitman, 2003). Severe damage (from the shock wave) to the ears can include tympanic membrane rupture, fracture of the ossicles, damage to the cochlea, hemorrhage, and cerebrospinal fluid leakage into the middle ear.
Criteria and thresholds for estimating the exposures from a single explosive activity on marine mammals were established for the Seawolf Submarine Shock Test Final Environmental Impact Statement (FEIS) (“Seawolf”) and subsequently used in the USS Winston Start Printed Page 33969S. Churchill (DDG-81) Ship Shock FEIS (“Churchill”) (DoN, 1998 and 2001a). NMFS adopted these criteria and thresholds in its final rule on unintentional taking of marine animals occurring incidental to the shock testing (NMFS, 2001a). Since the ship-shock events involve only one large explosive at a time, additional assumptions were made to extend the approach to cover multiple explosions for BOMBEX (A-S). In addition, this section reflects a revised acoustic criterion for small underwater explosions (i.e., 23 pounds per square inch [psi] instead of previous acoustic criteria of 12 psi for peak pressure), which is based on the final rule issued to the Air Force by NMFS (NMFS, 2005b).
For injury, NMFS uses dual criteria: eardrum rupture (i.e., tympanic-membrane injury) and onset of slight lung injury. These criteria are considered indicative of the onset of injury. The threshold for tympanic-membrane (TM) rupture corresponds to a 50 percent rate of rupture (i.e., 50 percent of animals exposed to the level are expected to suffer TM rupture). This value is stated in terms of an Energy Flux Density Level (EL) value of 1.17 inch pounds per square inch (in-lb/in 2), approximately 205 dB re 1 microPa 2-sec.
For this analysis, the use of multiple explosions only applies to the MK-83 bombs used in BOMBEX. Since BOMBEX events require multiple explosions, the Churchill approach had to be extended to cover multiple sound events at the same training site. For multiple exposures, accumulated energy over the entire training time is the natural extension for energy thresholds since energy accumulates with each subsequent shot (explosion); this is consistent with the treatment of multiple arrivals in Churchill. For positive impulse, it is consistent with Churchill to use the maximum value over all impulses received.
The first threshold is a 182 dB re 1 microPa 2-sec maximum energy flux density level in any 1/3-octave band at frequencies above 100 Hertz (Hz) for toothed whales and in any 1/3-octave band above 10 Hz for baleen whales. For large explosives, as in the case of the Churchill FEIS, frequency range cutoffs at 10 and 100 Hz make a difference in the range estimates. For small explosives (<1,500 lb NEW), as what was modeled for this analysis, the spectrum of the shot arrival is broad, and there is essentially no difference in impact ranges for toothed whales or baleen whales.
The TTS energy threshold for explosives is derived from the Space and Naval Warfare Systems Center (SSC) pure-tone tests for TTS (Schlundt et al., 2000; Finneran and Schlundt, 2004). The pure-tone threshold (192 dB as the lowest value) is modified for explosives by (a) interpreting it as an energy metric, (b) reducing it by 10 dB to account for the time constant of the mammal ear, and (c) measuring the energy in 1/3-octave bands, the natural filter band of the ear. The resulting threshold is 182 dB re 1 microPa 2-sec in any 1/3-octave band. The energy threshold usually dominates and is used in the analysis to determine potential Level B exposures for single explosion ordnance.
For this analysis, the use of multiple explosions only applies to FIREX (with IMPASS). Because multiple explosions would occur within a discrete time period, a new acoustic criterion—Start Printed Page 33970behavioral disturbance (without TTS)—is used to account for behavioral effects significant enough to be judged as harassment, but occurring at lower noise levels than those that may cause TTS.
The behavioral disturbance (without TTS) threshold for tones is derived from the SSC tests, and is found to be 5 dB below the threshold for TTS, or 177 dB re: 1 microPa2-s maximum EL in any 1/3-octave band at frequencies above 100 Hz for toothed whales/sea turtles and in any 1/3-octave band above 10 Hz for baleen whales. As stated previously for TTS, for small explosives (<1500-lb NEW), as what was modeled for this analysis, the spectrum of the shot arrival is broad, and there is essentially no difference in impact ranges for toothed whales/sea turtles or baleen whales. For BOMBEX involving MK-83 bombs, behavioral disturbance (without TTS) (177 dB re: 1 microPa2-s) is the criterion that dominates in the analysis to determine potential behavioral exposures (MMPA-Level B) due to the use of multiple explosions.
Table 3 summarizes the effects, criteria, and thresholds used in the assessment for impulsive sounds. The criteria for behavioral effects without physiological effects used in this analysis are based on use of multiple explosives that only take place during a BOMBEX event.
Injurious Physiological 50% Tympanic Membrane Rupture Energy flux density 1.17 in-lb/in2 (about 205 dB re 1 microPa2-sec) Level A.
Non-injurious Physiological TTS Greatest energy flux density level in any 1/3-octave band (>100 Hz for toothed whales and >10 Hz for baleen whales)—for total energy over all exposures 1 82 dB re 1 microPa2-sec Level B.
Non-injurious Behavioral Multiple Explosions Without TTS Greatest energy flux density level in any 1/3-octave (>100 Hz for toothed whales and > 10Hz for baleen whales)—for total energy over all exposures (multiple explosions only) 177 dB re 1 microPa2-sec Level B.
The criteria for mortality, Level A Harassment, and Level B Harassment resulting from explosive detonations were initially developed for the Navy's Sea Wolf and Churchill ship-shock trials and have not changed since other MMPA authorizations issued for explosive detonations. The criteria, which are applied to cetaceans and pinnipeds are summarized in Table 3. Additional information regarding the derivation of these criteria is available in the Navy's FEIS for the GOMEX Range Complex and in the Navy's Churchill FEIS (U.S. Department of the Navy, 2001).
Modeling was completed for four explosive sources (sequential detonation of four bombs per event) involved in BOMBEX with an assumed detonation depth of 1 m. The NEW used in simulations of the MK83 is 415.8 lbs. Start Printed Page 33971
Determining the zone of influence (ZOI) for the thresholds in terms of total EFD, impulse, peak pressure and 1/3-octave bands EFD must treat the sequential explosions differently than the single detonations. For the MK-83, two factors are involved for the sequential explosives that deal with the spatial and temporal distribution of the detonations as well as the effective accumulation of the resultant acoustics. In view of the ZOI determinations, the sequential detonations are modeled as a single point event with only the EFD summed incoherently:
The multiple explosion energy criterion was used to determine the ZOI for the Level B without TTS exposure analysis. Table 4 shows the ZOI results of the model estimation. The ZOI, when multiplied by the animal densities and total number of events (Table 1), provides the exposure estimates for that animal species for the given bomb source.
BOMBEX is restricted to one location (BOMBEX Hotbox). In addition to other mitigation measures (see Mitigation Measures section below), aircraft will survey the target area for marine mammals before and during the exercise. Ships will not fire on the target until the area is surveyed and determined to be free of marine mammals. The exercise will be suspended if any marine mammals enter the buffer area (5,100-yard or 4,663-m radius around target). The implementation of mitigation measures like these effectively reduce exposures in the ZOI.
Table 4—Estimated ZOIs (km2) Used in Exposure Calculations for BOMBEX Using MK-83 (415.8 lbs NEW) in the GOMEX Range Complex for Different Seasons
Estimated ZOI @ 182 dB re 1 μPa2-sec or 23 psi
98.93 115.93 161.39 173.27 55.53 76.82 137.33 158.07 4.84 4.84 4.84 4.98 <0.01 <0.01 <0.01 <0.01
Note: ZOIs for the MK-83 bombs are modeled as multiple detonations (4 bombs dropped in succession at same location).
Modeling was completed for the MK3A2 explosive anti-swimmer grenades, which assumed a 6 ft (1.8 m) detonation depth. The NEW used in simulations of the MK3A2 grenade is 0.5 lb.
Determining the ZOI for the thresholds in terms of total energy flux density (EFD), impulse, peak pressure and 1/3-octave bands EFD must treat the sequential explosions differently than the single detonations. For the MK3A2, two factors are involved for the sequential explosives that deal with the spatial and temporal distribution of the detonations as well as the effective accumulation of the resultant acoustics. In view of the ZOI determinations, the sequential detonations are modeled as a single point event with only the EFD summed incoherently:
The multiple explosion energy criterion was used to determine the ZOI for the non-injurious behavioral (without TTS) exposure analysis.
Table 5 shows the ZOI results of the model estimation. The ZOI, when multiplied by the animal densities and total number of events, provides the exposure estimates for that animal species. Grenade use is restricted to one location (UNDET Area E3) (see Figure 2 of the Navy's LOA application). In addition to other mitigation measures (see Mitigation Measures section below), lookouts will visually survey the target area for marine mammals. The exercise will not be conducted until the area is clear and will suspend the exercise if any enter the buffer area. Implementation of mitigation measures like these reduce the likelihood of exposure and potential effects in the ZOI.
Table 5—Estimated ZOIs (km2) Used in Exposure Calculations for Small Arms Training Using MK3A2 Anti-Swimmer Grenades (0.5 lbs NEW) in the GOMEX Range Complex for Different Seasons
4.94 5.45 4.71 5.81 1.80 2.18 1.96 3.27 0.09 0.09 0.09 0.10 <0.01 <0.01 <0.01 <0.01
Note: ZOIs for the MK3A2 bombs are modeled as multiple detonations (4 bombs dropped in succession at same location).
Explosions that occur in the GOMEX Study Area with the potential to impact marine mammals are associated with training during BOMBEX and small arms training events. Explosive ordnance use is limited to specific training areas. Within the GOMEX Study Area, explosive use associated with BOMBEX events occur in the BOMBEX Hotbox. The use of MK3A2 anti-swimmer grenades is associated with small arms training events, which are limited to the UNDET Area E3 box.
An explosive analysis was conducted to estimate the number of marine mammals that could be exposed to impacts from explosive ordnance use associated with BOMBEX and small arms training. Table 6 provides a summary of the explosive analysis modeling results.
Exposure estimates could not be calculated for several species (blue whale, fin whale, humpback whale, North Atlantic right whale, sei whale, and minke whale) because density data could not be calculated for the GOMEX Study Area due to the limited available data for these species; however, the likelihood of exposure for species not expected to occur in the GOMEX Study Area should be even lower than for the species with occurrence frequent enough for densities to be calculated. In addition to the low likelihood of exposure, the proposed mitigation measures presented below would be implemented prior to release of ordnance. Since the fin, North Atlantic right, humpback, blue, sei, and minke whale are considered rare in the GOMEX Range Complex, no exposures are expected for these species. In addition, the West Indian manatee is not expected to occur where explosive Start Printed Page 33972ordnance is used; therefore no exposures are expected for this species.
Lookouts will monitor the area before ordnance is used. Sperm whales will have high detection rates at the surface because of their large body size and pronounced blows; however, sperm whales are long, deep divers and may be submerged, and thus not visually detectable, for over an hour. It is likely that lookouts would detect Atlantic spotted dolphins, bottlenose dolphins, Clymene dolphins, pantropical spotted dolphins, Risso's dolphins, spinner dolphins and striped dolphins due to their gregarious nature and active surface behavior. Implementation of mitigation measures will reduce the likelihood of exposure and potential effects.
Table 6—Summary of Potential Exposures From Explosive Ordnance (Per Year) for Marine Mammals in the GOMEX Range Complex by the Navy Modeling
Potential exposures @177 dB re 1 microPa2-s (multiple detonations only)
Potential exposures @182 dB re 1 microPa2-s or 23 psi-ms
Potential exposures @205 dB re 1 microPa2-s or 13 psi-ms
Potential exposures @30.5 psi-ms
BOMBEX training 0 0 0 0
Small Arms training 0 0 0 0
BOMBEX training 1 1 0 0
BOMBEX training 6 6 0 0
Small Arms training 4 3 0 0
Total Exposures 10 9 0 0
BOMBEX training 3 3 0 0
Total Exposures 3 3 0 0
False killer whale:
Start Printed Page 33973
Melon-headed whale:
BOMBEX training 14 12 1 0
Total Exposures 14 12 1 0
BOMBEX training 14 13 1 0
Total Exposures 14 13 1 0
BOMBEX training 4 4 0 0
Total Exposures 4 4 0 0
In order to issue an incidental take authorization (ITA) under Section 101(a)(5)(A) of the MMPA, NMFS must prescribe regulations setting 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.” The NDAA 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.” The GOMEX Range Complex training activities described in this document are considered military readiness activities.
(2) A reduction in the numbers of marine mammals (total number or number at a biologically important time Start Printed Page 33974or location) exposed to underwater detonations or other activities expected to result in the take of marine mammals (this goal may contribute to (1), above, or to reducing harassment takes only).
NMFS reviewed the Navy's proposed mitigation measures, which included a careful balancing of the likely benefit of any particular measure to the marine mammals with the likely effect of that measure on personnel safety, practicality of implementation, and impact on the “military-readiness activity.” These mitigation measures are listed below.
8. Naval vessels will maneuver to keep at least 500 yds (460 m) away from Start Printed Page 33975any observed whale and avoid approaching whales head-on. This requirement does 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 operations, launching and recovering aircraft or landing craft, minesweeping operations, replenishment while underway and towing operations that severely restrict a vessel's ability to deviate course. Vessels will take reasonable steps to alert other vessels in the vicinity of the whale.
This activity occurs in the UNDET Area E3 of the GOMEX Study Area. The following mitigation measures are proposed by the Navy for the small arms training.
(A) Lookouts visually survey for floating weeds, algal mats, Sargassum rafts, marine mammals.
(B) A 200-yard (182-m) radius buffer zone will be established around the intended target. The exercises will be conducted only if the buffer is clear of sighted marine mammals and sea turtles.
This activity occurs in W-155A/B (hot box) area of the GOMEX Study Area. The location was established to be within 150 nm from shore-based facilities (the established flight distance restriction for F/A-18 jets during unit level training events). The following mitigation measures are proposed by the Navy for the BOMBEX training.
(A) Aircraft would visually survey the target and buffer zone for marine mammals prior to and during the exercise. The survey of the impact area would be made by flying at 1,500 feet altitude 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.
(B) A buffer zone of a 5,100-yard (4,663-m) radius would be established around the intended target zone. The exercises would be conducted only if the buffer zone is clear of sighted marine mammals and sea turtles.
(C) If surface vessels are involved, lookouts would survey for Sargassum rafts, which may be inhabited by immature sea turtles. Ordnance would not be targeted to impact within 5,100 yards (4,663 m) of known or observed Sargassum rafts or coral reefs.
(D) At-sea BOMBEXs using live ordnance will occur during daylight hours only.
In order to issue an ITA for an activity, Section 101(a)(5)(A) of the MMPA states that NMFS must set forth “requirements pertaining to the monitoring and reporting of such taking”. The MMPA implementing regulations at 50 CFR 216.104(a)(13) indicate that requests for LOAs must include the suggested means of accomplishing the necessary monitoring and reporting that will result in increased knowledge of the species and of the level of taking or impacts on populations of marine mammals that are expected to be present.
(2) An increase in our understanding of how many marine mammals are likely to be exposed to levels of underwater detonations or other stimuli that we associate with specific adverse effects, such as behavioral harassment, TTS, or PTS.
The Navy has provided NMFS with a copy of the draft GOMEX Range Complex Monitoring Plan. Additionally, NMFS and the Navy have incorporated a suggestion from the public, which recommended the Navy hold a peer review workshop to discuss the Navy's Monitoring Plans for the multiple range complexes and training exercises in which the Navy would receive ITAs.
The Navy must notify NMFS immediately (or as soon as clearance Start Printed Page 33976procedures allow) if the specified activity is thought to have resulted in the mortality or injury of any marine mammals, or in any take of marine mammals not identified in this document.
(A) MMOs selected for aerial or vessel surveys shall be placed on a Navy platform during one of the exercises being monitored per year. The remaining designated exercise(s) shall be monitored by the Navy lookouts/watchstanders.
During the public comment period on past proposed rules for Navy actions (such as the Hawaii Range Complex (HRC) and Southern California Range Complex (SOCAL) proposed rules), NMFS received a recommendation that a workshop or panel be convened to solicit input on the monitoring plan from researchers, experts, and other interested parties. The GOMEX Range Complex proposed rule included an adaptive management component and both NMFS and the Navy believe that a workshop would provide a means for Navy and NMFS to consider input from participants in determining whether (and if so, how) to modify monitoring techniques to more effectively accomplish the goals of monitoring set forth earlier in the document. NMFS and the Navy believe that this workshop concept is valuable in relation to all of the Range Complexes and major training exercise rules and LOAs that NMFS is working on with the Navy at this time. Consequently, NMFS has determined that this single Monitoring Workshop will be included as a component of all of the rules and LOAs that NMFS will be processing for the Navy in the next year or so.
The Navy, with guidance and support from NMFS, will convene a Monitoring Workshop, including marine mammal and acoustic experts as well as other interested parties, in 2011. The Monitoring Workshop participants will review the monitoring results from the Start Printed Page 33977previous two years of monitoring pursuant to the GOMEX Range Complex rule as well as monitoring results from other Navy rules and LOAs (e.g., VACAPES, AFAST, SOCAL, HRC, and other rules). The Monitoring Workshop participants would provide their individual recommendations to the Navy and NMFS on the monitoring plan(s) after also considering the current science (including Navy research and development) and working within the framework of available resources and feasibility of implementation. NMFS and the Navy would then analyze the input from the Monitoring Workshop participants and determine the best way forward from a national perspective. Subsequent to the Monitoring Workshop, modifications would be applied to monitoring plans as appropriate.
In addition to the site-specific Monitoring Plan for the GOMEX Range Complex, the Navy will complete the Integrated Comprehensive Monitoring Program (ICMP) Plan by the end of 2009. The ICMP is currently in development by the Navy, with Chief of Naval Operations Environmental Readiness Division (CNO-N45) having the lead. The program does not duplicate the monitoring plans for individual areas (e.g., AFAST, HRC, SOCAL, VACAPES); instead it is intended to provide the overarching coordination that will support compilation of data from both range-specific monitoring plans as well as Navy funded research and development (R&D) studies. The ICMP will coordinate the monitoring programs' progress towards meeting its goals and develop a data management plan. A program review board is also being considered to provide additional guidance. The ICMP will be evaluated annually to provide a matrix for progress and goals for the following year, and will make recommendations on adaptive management for refinement and analysis of the monitoring methods.
In combination with the 2011 Monitoring Workshop and the adaptive management component of the GOMEX Range Complex rule and the other Navy rules (e.g. VACAPES Range Complex, Jacksonville Range Complex, etc.), the ICMP could potentially provide a framework for restructuring the monitoring plans and allocating monitoring effort based on the value of particular specific monitoring proposals (in terms of the degree to which results would likely contribute to stated monitoring goals, as well the likely technical success of the monitoring based on a review of past monitoring results) that have been developed through the ICMP framework, instead of allocating based on maintaining an equal (or commensurate to effects) distribution of monitoring effort across range complexes. For example, if careful prioritization and planning through the ICMP (which would include a review of both past monitoring results and current scientific developments) were to show that a large, intense monitoring effort in Hawaii would likely provide extensive, robust and much-needed data that could be used to understand the effects of sonar throughout different geographical areas, it may be appropriate to have other range complexes dedicate money, resources, or staff to the specific monitoring proposal identified as “high priority” by the Navy and NMFS, in lieu of focusing on smaller, lower priority projects divided throughout their home range complexes.
If, as a result of the workshop and similar to the example described in the paragraph above, the Navy and NMFS decide it is appropriate to restructure the monitoring plans for multiple ranges such that they are no longer evenly allocated (by rule), but rather focused on priority monitoring projects that are not necessarily tied to the geographic area addressed in the rule, the ICMP will be modified to include a very clear and unclassified recordkeeping system that will allow NMFS and the public to see how each range complex/project is contributing to all of the ongoing monitoring programs (resources, effort, money, etc.).
NMFS proposes to include an adaptive management component in the final regulations governing the take of marine mammals incidental to Navy training exercises in the GOMEX Range Complex. The use of adaptive management will give NMFS the ability to consider new data from different sources to determine (in coordination with the Navy) on an annual basis if mitigation or monitoring measures should be modified or added (or deleted) if new data suggests that such modifications are appropriate (or are not appropriate) for subsequent annual LOAs, if issued.
Results from the Navy's monitoring from the previous year (either from GOMEX Range Complex or other locations).
Results from specific stranding investigations (either from GOMEX Range Complex or other locations).
Mitigation measures could be modified or added (or deleted) if new data suggests that such modifications would have (or do not have) a reasonable likelihood of accomplishing the goals of mitigation laid out in this proposed rule and if the measures are practicable. NMFS would also Start Printed Page 33978coordinate with the Navy to modify or add to (or delete) the existing monitoring requirements if the new data suggest that the addition of (or deletion of) a particular measure would more effectively accomplish the goals of monitoring laid out in this proposed rule. The reporting requirements associated with this rule are designed to provide NMFS with monitoring data from the previous year to allow NMFS to consider the data and issue annual LOAs. NMFS and the Navy will meet annually, prior to LOA issuance, to discuss the monitoring reports, Navy R&D developments, and current science and whether mitigation or monitoring modifications are appropriate.
The Navy shall submit a report annually on November 1 describing the implementation and results (through September 1 of the same year) of the GOMEX Range Complex Monitoring Plan, described above. Data collection methods will be standardized across range complexes to allow for comparison in different geographic locations. Although additional information will also be gathered, the MMOs collecting marine mammal data pursuant to the GOMEX Range Complex Monitoring Plan shall, at a minimum, provide the same marine mammal observation data required in major range complex training exercises section of the Annual GOMEX Range Complex Exercise Report referenced below.
With respect to the MMPA, NMFS' effects assessment serves four primary purposes: (1) To prescribe the permissible methods of taking (i.e., Level B Harassment (behavioral harassment), Level A harassment (injury), or mortality, including an identification of the number and types of take that could occur by Level A or B harassment or mortality) and to prescribe other means of affecting the least practicable adverse impact on such species or stock and its habitat (i.e., mitigation); (2) to determine whether the specified activity will have a negligible impact on the affected species or stocks of marine mammals (based on the likelihood that the activity will adversely affect the species or stock through effects on annual rates of recruitment or survival); (3) to determine whether the specified activity will have an unmitigable adverse impact on the availability of the species or stock(s) for subsistence uses (however, there are no subsistence communities that would be affected in the GOMEX Range Complex, so this determination is inapplicable for this rulemaking); and (4) to prescribe requirements pertaining to monitoring and reporting.
In the Assessment of Marine Mammal Response to Anthropogenic Sound section, NMFS' analysis identified the lethal responses, physical trauma, sensory impairment (permanent and temporary threshold shifts and acoustic masking), physiological responses (particular stress responses), and behavioral responses that could potentially result from explosive ordnance exposures. In this section, we will relate the potential effects to marine mammals from underwater detonation of explosives to the MMPA regulatory definitions of Level A and Level B Harassment and attempt to quantify the effects that might occur from the specific training activities that the Navy is proposing in the GOMEX Range Complex.
(5) Applied the applicable acoustic threshold criteria to the predicted sound exposures from the proposed activity. The results were then evaluated to Start Printed Page 33979determine whether the predicted sound exposures from the acoustic model might be considered harassment; and
(6) Considered potential harassment within the context of the affected marine mammal population, stock, and species to assess potential population viability. Particular focus on recruitment and survival are provided to analyze whether the effects of the action can be considered to have a negligible impact on marine mammal species or stocks.
These modeling results do not take into account the mitigation measures (detailed in the Mitigation Measure section above) that lower the potential for exposures to occur given standard range clearance procedures and the likelihood that these species can be readily detected (e.g., small animals move quickly throughout the water column and are often seen riding the bow wave of large ships or in large groups). Nevertheless, based on the modeling results, 2 Atlantic spotted dolphins, 19 bottlenose dolphins, 6 Clymene dolphins, 2 melon-headed whales, 26 pantropical spotted dolphins, 2 Risso's dolphins, 27 spinner dolphins, and 8 striped dolphins would be taken by Level B harassment (sub-TTS and TTS) as a result of the Navy training activities in the GOMEX Range Complex. In addition, 1 individual each of pantropical spotted dolphin and spinner dolphin would be taken by Level A harassment (injury). Please refer to Table 6 for a detailed list of marine mammals that would be taken as a result of the proposed Navy training activities within the GOMEX Range Complex. NMFS does not believe that there would be any mortality of any marine mammal resulting from the proposed training activities due to the sparse training activities and the implementation of mitigation and monitoring measures described above. Therefore, mortality of marine mammals would not be authorized. With the mitigation and monitoring measures implemented, the estimated take could be further reduced.
Marine mammal habitat and prey species could be affected by the explosive ordnance testing and the sound generated by such activities. Based on the analysis contained in the Navy's DEIS and the information below, NMFS has determined that the GOMEX Range Complex training activities will not have adverse or long-term impacts on marine mammal habitat or prey species.
The huge variation in fish populations, including numbers, species, sizes, and orientation and range from the detonation point, makes it very difficult to accurately predict mortalities at any specific site of detonation. A total of 7 hours explosive detonation events, with each event lasting for approximately 1 hour, are widely dispersed in two locations within the large GOMEX study area over the seasons for each year. Most fish species experience a large number of natural mortalities, especially during early life-stages, and any small level of mortality caused by the GOMEX Range Complex training exercises involving explosives will likely be insignificant to the population as a whole.
Therefore, potential impacts to marine mammal food resources within the GOMEX Range Complex are expected to be minimal given both the very geographic and spatially limited scope of most Navy at-sea activities including underwater detonations, and the high biological productivity of these resources. No short or long term effects to marine mammal food resources from Navy activities are anticipated within the GOMEX Range Complex.
In addition to considering estimates of the number of marine mammals that might be “taken” through behavioral harassment, NMFS must consider other factors, such as the likely nature of any responses (their intensity, duration, Start Printed Page 33980 etc.), the context of any responses (critical reproductive time or location, migration, etc.), as well as the number and nature of estimated Level A takes, the number of estimated mortalities, and effects on habitat.
The Navy's specified activities have been described based on best estimates of the planned detonation events the Navy would conduct for the proposed GOMEX Range Complex training activities. The events are generally short in duration, with each of the seven annual events lasting for about 1 hour. Taking the above into account, along with the fact that NMFS anticipates no mortalities (and few injuries) to result from the action, the fact that there are no specific areas of reproductive importance for marine mammals recognized within the GOMEX Range Complex, the sections discussed below, and dependent upon the implementation of the proposed mitigation measures, NMFS has determined that Navy training exercises utilizing underwater detonations will have a negligible impact on the affected marine mammal species and stocks present in the GOMEX Range Complex Study Area.
NMFS' analysis of potential behavioral harassment, temporary threshold shifts, permanent threshold shifts, injury, and mortality to marine mammals as a result of the GOMEX Range Complex training activities was provided earlier in this proposed rule and is analyzed in more detail below.
The Navy plans a total of 1 BOMBEX training event (with 4 bombs in succession for 1 hour) and 6 small arms training events (with 20 live grenades for each 1-hour event) annually. The total training exercises proposed by the Navy in the GOMEX Range Complex amount to approximately 7 hours per year. These detonation events are widely dispersed in two of the designated sites within the GOMEX Range Complex Study Area. The probability that detonation events will overlap in time and space with marine mammals is low, particularly given the densities of marine mammals in the GOMEX Range Complex Study Area and the implementation of monitoring and mitigation measures. Moreover, NMFS does not expect animals to experience repeat exposures to the same sound source as animals will likely move away from the source after being exposed. In addition, these isolated exposures, when received at distances of Level B behavioral harassment (i.e., 177 dB re 1 microPa 2-sec), are expected to cause brief startle reactions or short-term behavioral modification by the animals. These brief reactions and behavioral changes are expected to disappear when the exposures cease. Therefore, these levels of received impulse noise from detonation are not expected to affect annual rates or recruitment or survival.
Frequency—Available data (of mid-frequency hearing specialists exposed to mid- to high-frequency sounds—Southall et al., 2007) suggest that most TTS occurs in the frequency range of the source up to one octave higher than the source (with the maximum TTS at 1/2-octave above).
The Navy's model estimated that 1 pantropical spotted dolphin and 1 spinner dolphin could experience 50-percent tympanic membrane rupture or slight lung injury (Level A harassment) as a result of the training activities utilizing underwater detonation by BOMBEX in the GOMEX Range Complex Study Area. However, these estimates do not take into consideration the proposed mitigation and monitoring measures. For underwater detonations, the animals have to be within an area between certain injury zones of influence (ZOI) to experience Level A harassment. Such injury ZOI varies from 0.09 km2 to 4.98 km2 (or at distances between 169 m to 1,259 m from the center of detonation) depending on the types of munition used and the season of the action. Though it is possible that Navy observers could fail to detect an animal at a distance of more than 1 km (an injury ZOI during BOMBEX, which is planned to have 1 event annually), all injury ZOIs from small arms trainings are smaller than 0.1 km2 (178 m in radius) and NMFS believes it is unlikely that any marine mammal could be detected by lookouts/watchstanders or MMOs. As discussed previously, the Navy plans to utilize aerial or vessel surveys to detect marine mammals for mitigation implementation and indicated that they are capable of effectively monitoring safety zones.
Based on these assessments, NMFS determined that approximately 2 Atlantic spotted dolphins, 19 bottlenose dolphins, 6 Clymene dolphins, 2 melon-headed whales, 26 pantropical spotted dolphins, 2 Risso's dolphins, 27 spinner dolphins, and 8 striped dolphins could be affected by Level B harassment (TTS and sub-TTS) as a result of the proposed GOMEX Range Complex training activities. These numbers represent Start Printed Page 33981approximately 0.01%, 0.51%, 0.09%, 0.09%, 0.08%, 0.13%, 1.36%, and 0.24% of Atlantic spotted dolphins, bottlenose dolphins (Gulf of Mexico oceanic stock), Clymene dolphins, melon-headed whales, pantropical spotted dolphins, Risso's dolphins, spinner dolphins, and striped dolphins, respectively, in the vicinity of the proposed GOMEX Range Complex Study Area (calculation based on NMFS 2007 U.S. Atlantic and Gulf of Mexico Marine Mammal Stock Assessment).
Additionally, the aforementioned take estimates do not account for the implementation of mitigation measures. With the implementation of mitigation and monitoring measures, NMFS expects that the takes would be reduced further. Coupled with the fact that these impacts will likely not occur in areas and times critical to reproduction, NMFS has preliminarily determined that the total taking over the 5-year period of the regulations and subsequent LOAs from the Navy's GOMEX Range Complex training activities will have a negligible impact on the marine mammal species and stocks present in the GOMEX Range Complex Study Area.
NMFS has preliminarily determined that the issuance of 5-year regulations and subsequent LOAs (as warranted) for Navy training exercises in the GOMEX Range Complex would not have an unmitigable adverse impact on the availability of the affected species or stocks for subsistence use since there are no such uses in the specified area.
There are six ESA-listed marine mammal species that are listed as endangered under the ESA with confirmed or possible occurrence in the GOMEX Range Complex: humpback whale, North Atlantic right whale, fin whale, blue whale, sei whale, and sperm whale. The Navy has begun consultation with NMFS pursuant to section 7 of the ESA, and NMFS will also consult internally on the issuance of an LOA under section 101(a)(5)(A) of the MMPA for training exercises in the GOMEX Range Complex. Consultation will be concluded prior to a determination on the issuance of the final rule and an LOA.
The Navy is preparing an Environmental Impact Statement (EIS) for the proposed GOMEX Range Complex training activities. A draft EIS was released in November 2008 and it is available at http://www.gomexrangecomplexeis.com/​. NMFS is a cooperating agency (as defined by the Council on Environmental Quality (40 CFR 1501.6)) in the preparation of the EIS. NMFS has reviewed the Draft EIS and will be working with the Navy on the Final EIS (FEIS).
NMFS intends to adopt the Navy's FEIS, if adequate and appropriate, and we believe that the Navy's FEIS will allow NMFS to meet its responsibilities under NEPA for the issuance of the 5-year regulation and LOAs for training activities in the GOMEX Range Complex. If the Navy's FEIS is not adequate, NMFS will supplement the existing analysis and documents to ensure that we comply with NEPA prior to the issuance of the final rule or LOA.
Based on the analysis contained herein of the likely effects of the specified activity on marine mammals and their habitat and dependent upon the implementation of the mitigation measures, NMFS preliminarily finds that the total taking from Navy training exercises utilizing underwater explosives in the GOMEX Range Complex will have a negligible impact on the affected marine mammal species or stocks. NMFS has proposed regulations for these exercises that prescribe the means of affecting the least practicable adverse impact on marine mammals and their habitat and set forth requirements pertaining to the monitoring and reporting of that taking.
Pursuant to the Regulatory Flexibility Act, the Chief Counsel for Regulation of the Department of Commerce has certified to the Chief Counsel for Advocacy of the Small Business Administration that this rule, if adopted, would not have a significant economic impact on a substantial number of small entities. The Regulatory Flexibility Act requires Federal agencies to prepare an analysis of a rule's impact on small entities whenever the agency is required to publish a notice of proposed rulemaking. However, a Federal agency may certify, pursuant to 5 U.S.C. Section 605 (b), that the action will not have a significant economic impact on a substantial number of small entities. The Navy is the entity that will be affected by this rulemaking, not a small governmental jurisdiction, small organization or small business, as defined by the Regulatory Flexibility Act. This rulemaking authorizes the take of marine mammals incidental to a specified activity. The specified activity defined in the proposed rule includes the use of underwater detonations during training activities that are only conducted by the U.S. Navy. Additionally, the proposed regulations are specifically written for “military readiness” activities, as defined by the NDAA, which means they cannot apply to small businesses. Consequently, any requirements imposed by a Letter of Authorization issued pursuant to these regulations, and any monitoring or reporting requirements imposed by these regulations, will be applicable only to the Navy. Because this action, if adopted, would directly affect the Navy and not a small entity, NMFS concludes the action would not result in a significant economic impact on a substantial number of small entities. As a result, an initial regulatory flexibility analysis is not required and none has been prepared.
End Authority Start Printed Page 33982
(b) The taking of marine mammals by the Navy is only authorized if it occurs within the GOMEX Range Complex Operation Areas (OPAREAs), which is located along the southern east coast of the U.S. described in Figures 1 and 2 of the LOA application and consist of the BOMBEX Hotbox (surface and subsurface waters) and underwater detonation (UNDET) Area E3 (surface and subsurface waters), located within the territorial waters off Padre Island, Texas, near Corpus Christi NAS.
(1) The northernmost boundary of the BOMBEX Hotbox is located 23 nm (42.6 km) from the coast of the Florida panhandle at latitude 30° N, the eastern boundary is approximately 200 nm (370.4 km) from the coast of the Florida peninsula at longitude 86°48′ W.
(2) The UNDET Area E3 is a defined surface and subsurface area located in the waters south of Corpus Christi NAS and offshore of Padre Island, Texas. The westernmost boundary is located 7.5 nm (13.9 km) from the coast of Padre Island at 97°9′33′ W and 27°24′26″ N at the westernmost corner. It lies entirely within the territorial waters (0 to 12 nm, or 0 to 22.2 km) of the U.S. and the majority of it lies within Texas state waters (0 to 9 nm, or 0 to 16.7 km). It is a very shallow water training area with depths ranging from 20 to 26 m.
(B) Small Arms Training with MK3A2 anti-swimmer concussion grenade—up to 30 events over the course of 5 years (an average 6 events per year, with 20 live grenades used for each event).
(a) Under Letters of Authorization issued pursuant to § 216.106 of this chapter and § 218.36, the Holder of the Letter of Authorization may incidentally, but not intentionally, take marine mammals within the area described in § 218.30(b), provided the activity is in compliance with all terms, conditions, and requirements of this subpart and the appropriate Letter of Authorization.
(i) Bottlenose dolphin (Tursiops truncatus )—95 (an average of 19 annually);
(ii) Pantropical spotted dolphin (Stenella attenuata )—130 (an average of 26 annually);
(iii) Clymene dolphin (S. clymene)—30 (an average of 6 annually);
(iv) Atlantic spotted dolphin (S. frontalis)—10 (an average of 2 annually);
(v) Spinner dolphin (S. longirostris)—135 (an average of 27 annually);
(vi) Striped dolphin (S. coeruleoalba)—40 (an average of 8 annually);
(vii) Risso's dolphin (Grampus griseus)—10 (an average of 2 annually); (viii) Melon-headed whales (Peponocephala electra)—10 (an average of 2 annually);
(D) Lookouts shall be trained in the most effective means to ensure quick and effective communication within the command structure to facilitate implementation of protective measures if marine species are spotted. Start Printed Page 33983
(3) Proposed Mitigation Measures for Specific At-sea Training Events—If a marine mammal is injured or killed as a result of the proposed Navy training activities (e.g., instances in which it is clear that munitions explosions caused death), the Navy shall suspend its activities immediately and report such incident to NMFS.
(i) Air-to-Surface At-Sea Bombing Exercises (250-lbs to 2,000-lbs explosive bombs):
(C) A buffer zone of a 5,100-yard (4,663-m) radius shall be established around the intended target zone. The exercises shall be conducted only if the buffer zone is clear of sighted marine mammals.
(b) The Holder of the Authorization must notify NMFS immediately (or as soon as clearance procedures allow) if Start Printed Page 33984the specified activity identified in § 218.30(c) is thought to have resulted in the mortality or serious injury of any marine mammals, or in any take of marine mammals not identified in § 218.31(c).
(i) The Holder of this Authorization shall visually survey a minimum of 1 explosive event per year. One of the vessel or aerial surveys should involve NMFS-approved marine mammal observers (MMOs). If it is impossible to conduct the required surveys due to lack of training exercises, the missed annual survey requirement shall roll into the subsequent year to ensure that the appropriate number of surveys (i.e., total of five) occurs over the 5-year period of effectiveness of this subject.
(K) Observed behavior—Watchstanders shall report, in plain language and without trying to categorize in any way, the observed behavior of the animal(s) (such as animal closing to bow ride, paralleling course/speed, floating on surface and not swimming, etc.), including speed and direction;
(i) As required in § 218.34(c)(1), MMOs who are selected for aerial or vessel surveys shall be placed on a Navy platform during one of the explosive exercises being monitored per year, the other designated exercise shall be monitored by the Navy lookouts/watchstanders.
(vi) The MMOs shall collect species identification, behavior, direction of travel relative to the Navy platform, and distance first observed. Information collected by MMOs should be the same as those collected by Navy lookout/watchstanders described in § 218.34(c)(1)(iv).
(5) A method for standardizing data collection for GOMEX Range Complex and across range complexes,
(f) Annual GOMEX Range Complex Monitoring Plan Report—The Navy shall submit a report annually on November 1 describing the implementation and results (through September 1 of the same year) of the GOMEX Range Complex Monitoring Plan. Data collection methods shall be standardized across range complexes to allow for comparison in different geographic locations. Although Start Printed Page 33985additional information will also be gathered, the MMOs collecting marine mammal data pursuant to the GOMEX Range Complex Monitoring Plan shall, at a minimum, provide the same marine mammal observation data required in the data required in § 218.34(g). The GOMEX Range Complex Monitoring Plan Report may be provided to NMFS within a larger report that includes the required Monitoring Plan Reports from GOMEX Range Complex and multiple range complexes.
(g) Annual GOMEX Range Complex Exercise Report—The Navy shall provide the information described below for all of their explosive exercises. Until the Navy is able to report in full the information below, they shall provide an annual update on the Navy's explosive tracking methods, including improvements from the previous year.
(h) GOMEX Range Complex 5-yr Comprehensive Report—The Navy shall submit to NMFS a draft report that analyzes and summarizes all of the multi-year marine mammal information gathered during the GOMEX Range Complex exercises for which annual reports are required (Annual GOMEX Range Complex Exercise Reports and GOMEX Range Complex Monitoring Plan Reports). This report shall be submitted at the end of the fourth year of the rule (March 2014), covering activities that have occurred through September 1, 2013.
(i) The Navy shall respond to NMFS comments and requests for additional information or clarification on the GOMEX Range Complex Comprehensive Report, the Annual GOMEX Range Complex Exercise Report, or the Annual GOMEX Range Complex Monitoring Plan Report (or the multi-Range Complex Annual Monitoring Plan Report, if that is how the Navy chooses to submit the information) if submitted within 3 months of receipt. These reports will be considered final after the Navy has addressed NMFS' comments or provided the requested information, or three months after the submittal of the draft if NMFS does not comment by then.
To incidentally take marine mammals pursuant to these regulations, the U.S. citizen (as defined by § 216.103 of this chapter) conducting the activity identified in § 218.30(a) (the U.S. Navy) must apply for and obtain either an initial Letter of Authorization in accordance with § 218.26 or a renewal under § 218.27.
(3) A determination by the NMFS that the mitigation, monitoring and reporting measures required under § 218.33 and the Letter of Authorization issued under §§ 216.106 and 218.36 of this chapter, were undertaken and will be undertaken during the upcoming annual period of validity of a renewed Letter of Authorization.
(b) If a request for a renewal of a Letter of Authorization issued under § 216.106 of this chapter and § 218.37 indicates that a substantial modification to the described work, mitigation or monitoring undertaken during the upcoming season will occur, the NMFS will provide the public a period of 30 days for review and comment on the request. Review and comment on renewals of Letters of Authorization are restricted to:
(3) Compiled results of Navy funded research and development (R&D) studies (presented pursuant to the ICMP (§ 218.34(d)).
(4) Results from specific stranding investigations (either from the GOMEX Range Complex Study Area or other locations).
(a) Except as provided in paragraph (b) of this section, no substantive Start Printed Page 33986modification (including withdrawal or suspension) to the Letter of Authorization by NMFS, issued pursuant to §§ 216.106 and 218.36 of this chapter and subject to the provisions of this subpart shall be made until after notification and an opportunity for public comment has been provided. For purposes of this paragraph, a renewal of a Letter of Authorization under § 218.37, without modification (except for the period of validity), is not considered a substantive modification.
[FR Doc. E9-16537 Filed 7-13-09; 8:45 am]