Rough-toothed dolphins (Steno bredanensis) are reported to form isolated communities with stable groups around some oceanic islands. Within these communities, this species exhibits cooperative foraging and care-giving behavior including the sharing of large prey. These group behaviors could be driving community level structure where there are clear differences in habitat use between island groups, and limited movement among islands. Similar social characteristics are found in other cetacean species, e.g. killer whales, where individuals remain in maternally related groups indefinitely, forming “extended matrilines” as reflected by a single mitochondrial (mt) DNA haplotype. Here we test the hypothesis that rough-toothed dolphins also form “extended matrilines” using mtDNA control region haplotypes as a marker for maternal lineages. Alternatively, we test the influence of maternal fidelity on group structure within communities. The sample collection comprises adults from Pacific Ocean Islands and the continental Atlantic USA spanning 1976-2010. We sequenced mtDNA from 4 deceased groups (3 mass strandings and 1 bycatch; 350bp; n=28 teeth samples) and 14 living groups (460bp; n=106 skin samples) identifying 22 haplotypes. Differentiation and haplotype diversity were evaluated for groups within island communities in the Hawaiian Islands (Kauai and Hawaii) and Society Islands (Moorea and Raiatea) as well as between islands communities. Our results revealed multiple matrilines in 16 of the 18 groups, allowing us to reject the hypothesis of strict matrilineal structure. Although an AMOVA detected significant differentiation between island communities, groups did not significantly partition any genetic diversity within island communities. This is consistent with permutation tests where no strong signal of matrilineal influence was identified within island communities. Our study provides evidence of genetic structure at the community level, but demonstrates negligible structure at the group level. Fine-scale analyses to evaluate kinship and temporal association patterns are underway to further our understanding of group structure for this species.

Marine mammal (MM) monitoring was conducted during in-water pile driving (PD) at Hood Canal, Washington, during fall 2011. Monitoring was performed on construction days, during active-construction (“AC”, defined as 30 minutes prior to, during, and 30 minutes after PD) and non-construction (“NC”, downtime) periods. Baseline surveys were also conducted throughout Hood Canal on days when no PD occurred. Monitoring and baseline surveys occurred over 53 days. Marine Mammal Observers (MMOs) recorded 1,207 sightings totaling 2,269 individual MM.

Marine mammal (MM) monitoring was conducted during inwater pile driving (PD) at Naval Base Kitsap Bangor, Washington in Hood Canal during Fall 2011. Vessel-based monitoring was performed on construction days, during both active-construction (“AC”, defined as 30 minutes prior to, during, and 30 minutes after PD) and non-construction (“NC”, downtime) periods. Baseline surveys were also conducted throughout Hood Canal on days when no PD occurred. Monitoring and baseline surveys occurred over 53 days, during which Marine Mammal Observers (MMOs) recorded 1,207 sightings totaling 2,269 individual MM. Species observed included California sea lion (Zalophus californianus), Steller sea lion (Eumetopias jubatus), harbor seal (Phoca vitulina), and harbor porpoise (Phocoena phocoena). Harbor seals were the most frequently observed MM on construction days (n=782 sightings) and baseline survey days (n=197 sightings). The only cetaceans observed were harbor porpoise (n=68 construction, 34 baseline sightings). Harbor seal sighting rates were lower on construction days than on baseline days (0.73 and 1.80 sightings/observer hour [obs hr], respectively). Likewise, harbor porpoise were sighted less often on construction days than on baseline days (0.13 and 0.31 sightings/obs hr, respectively). On construction days, harbor seal sighting rates were actually higher during AC periods than NC periods (3.31 and 0.23 sightings/obs hr, respectively). This is consistent with MMOs’ qualitative observations that harbor seals (particularly juveniles) appeared to be attracted to PD, and often moved towards the construction area when PD was initiated. On construction days, pinnipeds were most often observed “diving,” “looking,” “sinking,” and “swimming”. During AC, 4% more pinnipeds were observed “diving” vs. NC periods (n=124). On construction days, harbor porpoise were most often observed “traveling”. During AC, 27% fewer harbor porpoise were observed “traveling” vs. NC periods (n=18). Overall, minor behavioral disruptions were observed in relation to PD, and were within “take” numbers in the issued Incidental Harassment Authorization.

The endangered North Atlantic humpback whale (Megaptera novaeangliae) migrates from six northern feeding grounds in the Gulf of Maine, the Gulf of St. Lawrence, Newfoundland/ Labrador, western Greenland, Iceland, and Norway to Caribbean Sea waters during the winter months (Katona and Beard 1990, Christensen et al. 1992, Palsbøll et al 1997). Understanding the occurrence and behavior of humpback whales in the vicinity of United States (U.S.) Navy training and vessel-transiting activities off the coast of Virginia is important in mitigating potentially harmful impacts on the species.

Baseline undisturbed behavior and social patterns of blue (Balaenoptera musculus) and fin whales (B. physalus) are not well described and are needed to identify and understand potential effects of anthropogenic activities. Behavioral data for blue and fin whales were collected during line-transect and focal-follow effort. Initially observed behavior state, heading, and minimum and maximum interindividual dispersal distance were recorded during line-transect sampling. Focal groups were circled for 10-60+ minutes and videotaped from outside Snell’s sound cone to avoid disturbance. During 24,736 km of survey effort, 51 fin whale sightings (85 individuals) and 49 blue whalesightings (81 individuals) were seen. Over 7 hours of video was collected for16 blue and 15 fin focal follows. During the summer seasons, blues (n=48) were seen more commonly than fins (n=35); in fall, fins (n=16) were seen significantly more frequently than blues (n=1). Mean group size was 1.7 whales for both species. Initially observed blue behavior was usually travel (85%) or mill (11%). Observed fin whale behavior was also mostly travel (90%), mill (4%), or surface-active travel (4%). Both species were seen socializing in fall but not summer; foraging was observed in summer through fall. Mean initial dispersal for blues and fins was 9.1 and 14.2 body lengths, respectively. In summer, blues were most frequently (26%) seen headed S; in fall (n=2), they were headed only inshore (E). In summer, fin whales were most commonly headed SSW (26%) or WNW (26%); in fall, they were headed mostly NE (38%) or WSW (38%). Dive/respiration/behavioral event rates were also collected. Both species may directly compete for food based on observations of inter-specific maneuvering for a bait ball. Data represent the most extensive record of systematic undisturbed behavior on these species in SOCAL and include social interactions not previously documented in this region.

Baseline undisturbed behavior and social patterns of blue (Balaenoptera musculus) and fin whales (B. physalus) are not well described and are needed to identify and understand potential effects of anthropogenic activities in the SCB. In 2008-2012, 72,467 km of aerial line transect and focal-follow effort was conducted in the SCB. Initially observed location, group size, behavior state, heading, and minimum and maximum inter-individual dispersal distance were recorded. Focal groups were circled for 10-60+ minutes and videotaped from outside the plane’s sound cone to avoid disturbance. A total of 122 fin whale sightings (208 individuals) and 65 blue whale sightings (104 individuals) were made. Behavior, occurrence and distribution were related to season, location, bathymetry, and time of day. Blue whales were seen only from summer-fall and concentrated primarily close to shore (

Baseline undisturbed behavior/social patterns of blue/fin whales are not well described and are needed to identify and understand potential effects of anthropogenic activities. Behavioral data were collected during aerial effort. Initially observed behavior state, heading, minimum/maximum inter-individual dispersal distance were recorded during line-transect sampling. During the summer seasons, blues were seen more than fins; in fall, fins were seen more. Initially observed blue behavior was usually travel or mill. Observed fin behavior was mostly travel, mill, or surface-active travel. Both species were seen socializing in fall but not summer; foraging was observed in summer through fall. In summer, blues were seen headed S; in fall, headed inshore. In summer, fins were headed SSW or WNW; in fall, they were headed NE or WSW. Data represent the most extensive record of systematic undisturbed behavior on these species in SOCAL and include social interactions not previously documented in this region.

Baseline undisturbed behavior and social patterns of blue (Ba/aenoptera musculus) and fin whales (8. physa/us) are not well described and are needed to identify and understand potential effects of anthropogenic activities. Behavioral data for blue and fin whales were collected during aerial survey line-transect and focal-follow effort. Initially-observed behavior state, group size, heading, and minimum and maximum inter-individual dispersal distance were recorded during line-transect sampling and / or subsequent verification circling by the aircraft. Focal groups were circled for 3- 60+ minutes and videotaped from outside Snell's sound cone to avoid disturbance. During 24,736 km of survey effort, 51 fin whale sightings (86 individuals) and 49 blue whale sightings (84 individuals) were seen . Over 7 hours of video was collected for 16 blue and 15 fin focal follows. During the summer, blues (n=48) were seen more commonly than fins (n=35); in fall, fins (n=16) were seen much more frequently than blues (n= 1 ). Mean group size was 1. 7 whales for both species. Initially observed blue behavior was usually travel (85%) or mill (11%). Observed fin whale behavior was also mostly travel (87%), mill (6%), or surface-active travel (3%). Both species were seen socializing (e.g., touching) in fall but not summer; foraging was observed in summer through fall. Mean initial dispersal for blues and fins was 8 and 16 body lengths, respectively. In summer, blues were most frequently (26%) seen headed S; in fall (n=2), they were headed only inshore (E). In summer, fin whales were most commonly headed SSW (26%) or WNW (26%); in fall, they were headed mostly NE (38%) or WSW (38%). Both species directly compete for food based on observations of inter-specific maneuvering for a bait ball. Data represent the most extensive record of systematic undisturbed behavior on these species in SOCAL and include social interactions not previously documented in this region. Dive / respiration / behavioral event rates were also collected and are currently being analyzed. Bacon, C., M.A. Smultea, B. Wursig, K. Lomac-MacNair, and J. Black.

Fifteen aerial surveys (72,647 km) occurred during 2008-2012 to monitor occurrence, abundance, and behavior of marine mammals in the Southern California Bight (SCB) on behalf of the U.S. Navy. Thirty-six (2%) of 2,151 total sightings of at least 11 species were mixed-species associations (i.e., at least two different species swimming together/interacting). Little is known about these associations. Risso’s dolphins were most frequently associated with another marine mammal species (19 [7%] of 238 total Risso’s sightings) as follows: with sperm whales (1x), California sea lions (CaSL) (3x), and bottlenose (7x), northern right whale (NRWD) (4x), long-beaked common (1x), unidentified (1x), and common dolphin sp. (2x). Up to 3 species occurred together on 3 different occasions: (1) sperm whales/Risso’s/NRW dolphins, (2) Risso’s/unidentified dolphins/CaSL, and (3) Pacific white-sided/common dolphins with CaSL. The most unusual mixed species sighting was 24 sperm whales (including 4 calves) with 11 Risso’s and ~50 NRW dolphins: Risso’s repeatedly charged adult sperm whales’ heads who responded by dropping their lower jaw, perhaps related to kleptoparasitism. Potential reasons for mixed-species associations include increased protection from predators via dilution, increased prey detection/consumption, and “play” (i.e., fin whale calf touching NRWD). Data include interactions not previously documented in the SCB among these socially complex animal groups.

Effects of mixed-species associations (MSA [at least two different species swimming together and / or inte racting]) on cetacean behavior rarely have been quantified, but are important for identifying and differentiating potential anthropogenic impacts . Baseline marine mammal behavior was assessed during 83 ,005 km of U.S. Navy supported aerial line-transect surveys in the Southern California Bight during 2008-2013.

Effects of mixed-species associations (MSA [at least two differentspecies swimming together and/or interacting]) on cetacean behavior rarely have been quantified, but are important for identifying and differentiating potential anthropogenic impacts. Baseline marine mammal behavior was assessed during 77,390 km of U.S. Navy supported aerial line-transect surveys in the Southern California Bight during 2008-2013. Multinomial logistic regression was used to assess effects of MSA on group size, maximum nearest neighbor distance (a “cohesion” index, in body lengths), behavior state, and heading. Two percent (43) of 2,330 sightings were MSA involving 13 species (5 baleen whales, 7 toothed whales, 1 pinniped). Behavior and group size of some species differed significantly in MSA vs. non-MSA. MSA were predominated by Risso’s dolphins (44%; 19 of 43 MSA). Risso’s dolphins were most frequently associated with bottlenose dolphins (37% of 19 Risso’s MSA groups) followed by northern right whale dolphins (NRWD; 3% of 19). Risso’s dolphins tended to change headings more often in MSA (p

In Hawai'i fishermen use a variety of hook and line methods to catch tuna associated with pantropical spotted dolphins. In response to reports of dolphins being hooked in fisheries, the National Marine Fisheries Service (NMFS) proposed recategorizing two fisheries ("charter vessel" and "trolling, rod and reel") in 2011 from Category III (those having a remote likelihood of serious injury/mortality) to Category II (those having occasional serious injury/mortality). After reviewing comments received in response to the proposal, NMFS did not re-categorize the fisheries, in part because of statements that fishing effort around dolphins may have been overestimated and that many vessels just trolled near dolphins, not through groups. We used photo-identification of individually distinctive vessels fishing in association with dolphin groups and observations on the number and behavior of vessels with dolphins to examine the extent and nature of interactions between fishing vessels and spotted dolphins off Hawai'i Island. Since 2010, 34.5% of spotted dolphin encounters had fishing vessels present within the group envelope of the dolphins (mean=3.7, SD=3.5, range=1-19, n=57 of 165 encounters). Two primary fishing methods were used, either trolling through groups of dolphins or repeatedly transiting through a group at high speed to the advancing front of the group and stopping and fishing as the group passed by, with some vessels alternating methods during encounters. Since 2010, 133 different vessels were documented fishing in association with dolphins; of these, 38 (28.6%) were documented on two or more occasions, and 26 were documented in two or more years. A mark-recapture abundance estimate of the number of vessels fishing in association with spotted dolphins in 2012 and 2013 was 322 (CV=0.05). In 2015 NMFS recognized three distinct island-associated populations of spotted dolphins in Hawai'i, including one off Hawai'i Island, thus the population of dolphins involved in these interactions is smaller than originally expected. While many factors likely influence the probability of boats fishing associated with dolphin groups, continued reports of occasional hooking combined with the relatively large number of vessels "fishing" dolphins suggest the fisheries categories should be re-evaluated.

Currently a single stock of short-finned pilot whales is recognized in Hawaiian waters, with an estimated abundance of over 12,000 individuals in the EEZ. However, preliminary genetic results suggest that pilot whales around the main Hawaiian Islands are reproductively isolated from those elsewhere in the tropical Pacific. Since the type and extent of anthropogenic interactions varies both among the main Hawaiian Islands and offshore, we test the hypothesis that there is only a single stock of this species in Hawai‘i using a combination of association analyses of photo-identification data and movement/habitat use analyses from satellite tags. Photographs over 13 years included over 6,500 identifications of 868 distinctive individuals. Satellite tag data from 64 deployments averaged 37 days (max=228 days). Combining tag and association analyses indicate individuals do not mix freely among the islands and suggest the existence of three socially isolated but partially overlapping insular communities and an offshore population. The ranges of the three insular communities are from Ni‘ihau to western O‘ahu, from O‘ahu to Lana‘i, and primarily off Hawai‘i Island. Tagged individuals from these insular communities (n=61 deployments) remained an average of 57.5 km from their tagging location, with a grand mean of depth used and distance from shore of 1,564 m and 15.2 km, respectively. Evidence for an offshore population comes from three individuals tagged in two isolated social clusters with mean distances from their tagging locations of 249 km, with a grand mean of depth used and distance from shore of 4,336 m and 81.1 km (max=381 km) respectively. Anthropogenic interactions vary among the population ranges, with long-line fishing in offshore waters, Navy activities primarily off Ni‘ihau, Kaua‘i and O‘ahu, and vessel-based whale watching and swim-with operations primarily off Hawai‘i Island. As each community is exposed to different anthropogenic threats they should be managed independently.

The Virginia Aquarium Foundation (VAQF) and the U.S. Navy have been working together since 2013 to determine the efficacy of using acoustic telemetry for investigating the fine scale movements of sea turtles in the vicinity of Navy facilities in southeastern Virginia. To date, we have deployed 56 acoustic tags (VEMCO V16, V13 and V9 69 kilohertz tags), 14 from Jul-Nov of 2013, 24 in 2014 and 18 May-Jul of 2015. The U.S. Navy maintains an array of 71 acoustic receivers (VEMCO VR2W) in southeastern Virginia and downloads and processes data every other month. There is a four to six month delay from the time of detection to VAQF receiving processed tag detection data. For this reason, we will discuss results for turtles tagged in 2013 and 2014. Of the 38 turtles tagged in 2013-14, five were wild caught (incidentally or directly captured) and 33 were stranded, rehabilitated and released. Of the stranded turtles, 14 were caught on recreational hook and line, 13 were cold-stunned and the rest were boat strikes (n=3), diseased (n=2) or entangled in other gear (n=1). In total we deployed tags on 18 loggerheads, 15 Kemp’s ridleys (one was released twice) and 4 green turtles. Of these 15 (83%) of the loggerheads were detected, 11 (73%) of the Kemp’s ridleys were detected and 3 (75%) of the greens were detected. Seven of the turtles stranded dead since release (3 wild and 4 stranded) and of these one was never detected. Seven turtles were released after mid-Oct south of the Navy receiver array and, of these, four were never detected. For loggerheads, Kemp’s and greens that were detected, mean number of detections were 220, 57, and 187, number of different days detected were 6, 3, and 10, and days post-release were 97, 21, and 53 respectively.

Marine ambient sound was recorded on autonomous high-frequency acoustic recording packages (bandwidth 10 Hz to 100 kHz) during long term deployments at multiple sites across the North Pacific, from the high latitude Aleutian Islands to tropical Palmyra Atoll in depths of 600–1 000 m. Most intertropical but no temperate locations showed a distinct diel pattern in ambient sound. The soundscape at each location was unique, yet there was a similar recurring sound of unknown origin in lower latitude locations. This sound had a peak frequency around 3–5 kHz and was recorded only for several hours after sunset. Additionally, at some locations, a broadband acoustic signal with bandwidth up to 60 kHz was recorded at night with crepuscular peaks. Both sound patterns were lunar dependent with lower acoustic levels during full moon phases. Site-specific diel and seasonal acoustic patterns have been observed for various odontocete species. Correlations between odontocete presence and levels of ambient sound are investigated. [Work supported by NOAA-Pacific Islands Fisheries Science Center, US Navy-N45/PACFLT, ONR, Pacific Life, Ocean Foundation, University of California, San Diego.]

Evidence from strandings and anecdotal reports indicate that a number of odontocete species interact with near-shore fisheries in Hawai'i. In the absence of observer programs in these fisheries, we evaluated mouthline injuries from known resident populations of false killer whales and pygmy killer whales, to assess the viability of this method to document injuries associated with hook and line fishery interactions. All individuals with mouthlines visible were selected from photo-ID catalogs and scored for presence of mouthline injuries consistent with fisheries interactions. Ninety-seven false killer whales and 47 pygmy killer whales had ≥50% of the mouthline visible using fair to excellent quality photos, with a mean of 67% and 59% mouthline visible, respectively. Preliminary analysis suggests that main Hawaiian Islands insular false killer whales have high rates of mouthline injuries- 20% of adult and sub-adult individuals with ≥50% mouthline visible have injuries consistent with fisheries interactions, supporting studies using dorsal fin injuries that indicate individuals from this population regularly interact with fisheries. Pygmy killer whales also appear to interact with fisheries at high rates. Of adult and sub-adult individuals off Hawai'i and O'ahu with ≥50% of the mouthline visible, 31% have injuries consistent with fisheries interactions. Since pygmy killer whales feed primarily at night, and there are few reports of them depredating lines, mouthline injury analysis provides new insight into fisheries interactions for this species. Scars on pygmy killer whales heal white and are easier to detect than healed injuries on false killer whales, thus a greater proportion of individuals with such injuries may be detected for pygmy killer whales. With both species, the proportion of mouthline visible increased the likelihood of mouthline injuries being detected. Injury rates are negatively biased, since those individuals scored as having no mouthline injury may not have had their entire mouthline visible. Further efforts will aim to identify injury rates in short-finned pilot whales and rough-toothed dolphins. An examination of differences in injury rates between age classes, and multi-species comparisons will also be undertaken to better understand fisheries interactions.

The Integrated Comprehensive Monitoring Program (ICMP) provides an overarching framework for coordination of U.S. Navy marine species monitoring. It is intended for use as a planning tool to focus Navy monitoring priorities pursuant to ESA and MMPA requirements and as an adaptive management tool to analyze and refine monitoring and mitigation techniques over time. It has been developed in direct response to Navy Range permitting requirements established in the various MMPA Final Rules, ESA consultations, and other applicable regulations. In early 2011 the Navy established a Scientific Advisory Group (SAG) consisting of experts in marine mammal ecology, passive acoustic monitoring, and cetacean behavior. The Navy convened the SAG with the initial task of evaluating current monitoring approaches under the ICMP and existing Letters of Authorization and developing objective scientific recommendations that will serve as the basis for a Strategic Plan for Navy monitoring. The Strategic Plan will be integrated as a primary component of the ICMP and provide a comprehensive 3-5 year “vision” for Navy monitoring across geographic regions - serving as guidance for determining how to most efficiently and effectively invest the U.S. Fleet marine species monitoring budget to address ICMP objectives and satisfy Marine Mammal Protection Act Letter of Authorization regulatory requirements for Fleet testing and training activities.

Rapid progress and affordability of photographic technology with increasing improvements in image resolution have facilitated advancements in efficiency and alternative approaches in data collection for marine mamma ls. We report these recent improvements by comparing marine mammal photographs taken during 2008-2013 aerial surveys of 16 marine mammal species in the Southern California Bight, shore-based studies of bottlenose dolphins (Tursiops truncatus) in Galveston Bay, Texas (2011 - 2013), and gray whales (Eschrichtius robustus) off Sakhalin Island, Russia (2004 -2010).

Rapid progress and affordability of photographic technology with increasing improvements in image resolution have facilitated advancements in efficiency and alternative approaches in data collection for marine mammals. We report these recent improvements by comparing marine mammal photographs taken during 2008-2013 aerial surveys of 16 marine mammal species in the Southern California Bight, shorebased studies of bottlenose dolphins (Tursiops truncatus) in Galveston Bay, Texas (2011-2013), and gray whales (Eschrichtius robustus) off Sakhalin Island, Russia (20042010). Various Canon and Nikon high-definition cameras ranging from 8.2-36.3 MP resolution and 70-1600 mm lenses with image stabilization were used during the studies. Results of these photographic comparisons demonstrate the evolution of digital photography advancements with the successful capture of individuals, as well as detailed information for behavioral ecology studies. For example, (1) individual identification of marine mammal species from aircraft not previously reported (Risso’s dolphins (Grampus griseus), killer whales (Orcinus orca), and blue and fin whales (Balaenoptera musculus and B. physalus)), (2) shore-based individual identification of bottlenose dolphins up to 500 m and of gray whales up to 2 km from shore, (3) instantaneous differentiation/confirmation of short-beaked vs. long-beaked common dolphins (Delphinus delphis and D. capensis) from 1,500-ft altitude with a 36 MP camera, (4) reduced proportion of “unidentified” dolphin and whale species, and (5) potential tracking of the behavior, social associations and durations, and relative position within the group of some individually identified delphinids and other species not previously studied in this manner. High- definition digital photography reduces costs and acquisition/processing time from earlier “tried and true” analog photography. This facilitates, advances, and compliments the efficacy of data collection for population and behavioral ecology studies on marine mammals, most recently allowing capture of individual identification images at distances of up to 2 km away.

The U.S. Navy's Atlantic Fleet conducts training and testing activities within the Northwest Atlantic Ocean and Gulf of Mexico, including the use of active sonar and explosives. While training and testing activities have the potential to impact the environment, the Navy employs every means available, without jeopardizing the safety of Sailors or impacting military readiness, to mitigate the potential environmental effects of these activities. Prior to training and testing activities, the Navy consults extensively with environmental regulators to determine appropriate mitigations to protect marine species, particularly marine mammals. Additionally, in order to evaluate the impacts of Navy activities on marine mammals and other protected species, the Navy has implemented a monitoring program to collect data on baseline animal presence, as well as exposure and response to Navy training and testing activities. Passive acoustic monitoring remains a cornerstone of addressing revised long term objectives of the monitoring program, and continues to provide key data on marine mammal presence and behavior. Future work will focus on species classification and animal behavior before, during, and after exposure to potential stressors. This presentation will provide an overview of Navy environmental compliance in the Atlantic, including monitoring efforts. This presentation will also discuss the tools and processes that Navy uses to assess the potential impacts of activities, how mitigation is used to reduce those impacts, and protective measures such as the restrictions employed in the North Atlantic right whale critical habitat areas. The Navy remains committed to marine stewardship and responsible management of the potential impacts of training and testing activities on protected species.

The U.S. Navy’s Atlantic Fleet conducts training and testing activities within the Northwest Atlantic Ocean and Gulf of Mexico, including the use of active sonar and explosives. In order to evaluate the impacts of these activities on marine mammals and other protected marine species, the Navy implemented a monitoring program to collect data on baseline animal presence, as well as exposure and response to Navy training and testing activities. Passive acoustic monitoring is an important component of the Navy’s monitoring efforts. Between 2009 and 2013, the Navy utilized effort-based monitoring metrics and targeted a number of different training and testing events for monitoring. Passive acoustic data was collected to monitor mysticete migration patterns in the mid-Atlantic, the effects of MFAS on odontocete vocalizations in North Carolina and Florida, and the potential effects of explosive training events off the coast of Virginia Beach, VA. Platforms included Marine Autonomous Recording Units (MARUs), High Frequency Acoustic Recording Packages (HARPs), Ecological Acoustic Recorders (EARs), and sonobuoys, among others. Additionally, the Marine Species Monitoring Program has funded the deployment of acoustic recording tags on several marine species including pilot whales and North Atlantic right whales, as well as behavioral response playback experiments with short-finned pilot whales off Cape Hatteras, North Carolina. In November 2013, the Navy began replacing effort-based monitoring metrics with objective based monitoring projects as a result of new environmental permits for Atlantic Fleet Training & Testing (AFTT). Passive acoustic monitoring remains a cornerstone of the revised long term goals, and continues to provide key data on marine mammal presence and behavior. Future work will focus on species classification and animal behavior.

Aerial surveys provide a valuable platform to record and document behavior of marine mammals above and below the sea surface. This approach is advantageous in avoiding disturbance from the observational platform while circling outside the sound cone of the plane. Since 2008, the U.S. Navy has instituted a marine mammal monitoring program in southern California from several platforms, including aerial surveys, and has successfully captured previously undocumented behaviors and species interactions during the aerial effort. This included focal behavioral interactions between sperm whales, northern right whale dolphins, and Risso's dolphins on 14 May 2011, 24 nm west of San Diego, CA. This -1.5-hour encounter was documented in detail with high- definition digital photographs and video as the group traveled NE along the edge of a steep underwater drop-off. Risso's dolphins initiated charges towards the heads of the sperm whales on multiple occasions, followed by fast retreats. Sperm whale adults responded by displaying an open lower jaw. Risso's dolphins appeared to direct this behavior only toward adult sperm whales that had recently surfaced from long (> 20 min) dives; it was not directed toward the four calves in the group. Northern right whale dolphins intermingled with the Risso's dolphins and sperm whales, although they did not approach sperm whales as closely or abruptly as the Risso's dolphins. While similar apparently aggressive Risso's dolphin behavior has been documented toward other cetacean species, this is the first known occurrence of head-on charging by Risso's dolphins, accompanied by the elicited jaw display response from sperm whales. The interaction may be similar to aggressive pilot whales behavior towards sperm whales, and may function in acquiring regurgitated sperm whale food, or other needs by the Risso's dolphins.

Passive acoustic monitoring was conducted during a survey of marine mammals in nearshore waters surrounding Pagan Island, a remote volcanic island in the western tropical Pacific, part of the Commonwealth of the Northern Marianas Islands. The objective was to collect baseline information for Department of Defense's CNMI Joint Military Training Environmental Impact Statement. The primary effort was conducted over 11 days in August 2013. Visual/acoustic line-transect surveys were conducted using a towed hydrophone array system during daytime, and moored sonobuoys were deployed at night. Fourteen acoustic encounters occurred during line-transect surveys consisting of the following (subtotal in parentheses): bottlenose dolphin (1), spinner dolphin (1), beaked whales (4), and unidentified dolphins (8). Of this total, eleven were acoustic only encounters and three were concurrently sighted by observers. The four beaked whale acoustic encounters could not be classified in the field so data were post-processed resulting in the following classifications: Blainville's beaked whales (3) and Cuvier's beaked whale (1). Localization ranges (perpendicular to trackline) were between 0.3 and 2 km and varied by species/species groups. Sonobuoys were moored in depths of 30-50m at two sites located off sand beach areas on the west side of the island. Approximately 67 hours of recordings were made for an average recording duration of 7.4 hours per night. The majority of detection events (55) were of dolphins (undetermined species). Sperm whales were detected once by each sonobuoy. In summary, passive acoustic methods were able to detect delphinids, as well as deep diving species during both line-transect surveys and shallow water sonobuoy monitoring sites. Although brief in duration, this effort provided important information about the occurrence of several species of marine mammals documented for the first time at this remote island.

Beaked whales are among the most poorly understood marine mammals. They are deep-diving odontocetes, spending most of their time submerged with infrequent, short surface intervals. Due to this behavior, they are difficult to study using visual observation methods alone . However, recent advancements in passive acoustic detection and survey techniques have shown to provide viable methods for stu dying beaked whales (Yack et al. 2013). In the Gulf of Alaska (GOA), there is little known abo ut beaked whale abundance and distribution.

A protected species monitoring program was initiated in 2007 when the US Navy identified Onslow Bay, NC as a potential site for an Undersea Warfare Training Range. To estimate marine mammal density, distribution and seasonality, traditional visual line transect surveys from both aerial and vessel platforms have been augmented with passive acoustic monitoring techniques. In 2010, 20 aerial (10,939 km of trackline) and 14 vessel (958 km of trackline) survey days were completed. In order of decreasing frequency Tursiops truncatus, Stenella frontalis, Grampus griseus, Globicephala macrorhynchus, Delphinus delphis, and Balaenoptera physalus were sighted. T. truncatus and S. frontalis comprised most sightings in both aerial (85%) and vessel (100%) surveys. Approximately 1,000 digital images were taken for species and individual identification during vessel‐based surveys. To date, six T. truncatus and one S. frontalis have been re‐sighted across seasons and years, suggesting some degree of residency in the study area. Passive acoustic monitoring techniques include towing a four‐element hydrophone array during vessel surveys and deploying High‐frequency Acoustic Recording Packages (HARPs) on the sea floor. Analysis of towed array recordings suggests that visual surveys detect approximately half of the dolphin groups that were acoustically detected. Hundreds of vocal detections are present in the HARP data, which will provide insights into of diel and seasonal patterns of marine mammal vocalization. This project, now in its fourth year, is providing a valuable long‐term window into abundance and residency patterns of cetaceans in offshore waters of North Carolina. 

Measurements of underwater noise from pile driving have been collected in San Diego Bay during a marine construction project, to inform placement of marine mammal observers, and adhere to Incidental Harassment Authorization (IHA) requirements. This presentation will focus on a subset of these measurements made with a hand-held device, or Underwater Sound Level Meter (USLM). The USLM employs an intuitive operating menu, requires no specialized training, and rapidly delivers fully calibrated results expressed in the relevant metric, such as peak level, rms level and sound exposure level. Several examples will be discussed involving the documentation of isopleths associated with the 190 dB and 180 dB isopleths (rms level, dB re 1 µPa) that define Level A injury thresholds for pinnipeds and cetaceans, respectively. One represents a unique set of measurements made during which the USLM documented the evolution of the underwater sound field from impact pile driving versus range every approximately 5 m. This made possible by recording from a small vessel that slowly opened in range from the pile source (the USLM also records its own position via GPS. ) The results of such fine-scale range sampling are also compared with modeling of transmission loss with range from the pile. Stakeholders in both industry and government share the same goal of rapid, calibrated measurements of underwater noise to protect marine life and comply with statuary environmental regulations. The USLM is a time and labor saving device that meets this goal.

A shore-based platform, incorporating high-powered 25×150mm binoculars ("bigeyes"), was evaluated as an alternative approach for surveying marine areas for protected species (marine mammals and sea turtles). During a pilot study at a test site on Oahu (273m elevation), humpback whale blows were visible through bigeyes 37km away in Beaufort Sea State (BSS) 2. This suggests the approach could be effective at detecting baleen and sperm whales from long distances, priority species under the U.S. Navy's Marine Species Monitoring Program. Systematic scans using bigeyes were performed in Guam over 20 days from a north-facing (193m) and a northeast-facing (157m) shore station in May 2014 and March 2015. These two sites were chosen because of mostly unobstructed views of the ocean, as well as generally high BSS that prohibit visual surveys from small vessels in this area. A SnapZoom digiscoping adapter, equipped with an iPhone or GoPro, was attached to the bigeye eyepiece allowing collection of photos and video, complementing supertelephoto (500-800mm) photography on a DSLR to assist with species confirmation. Observers recorded 33 odontocete sightings comprised of 4 confirmed species (spinner and bottlenose dolphins, pilot and melon-headed whales), but no baleen or sperm whales were observed. Several sightings were distant from shore, including two unidentified dolphins observed 9 km offshore in BSS 6, cued by diving birds, and a group of 160 melon-headed whales 14km offshore in BSS 5. The species observed and the sighting rate of 0.28 per hour, or 1.7 per day, were comparable to results from smallvessel surveys in Guam, suggesting an overall low density of marine mammals, and large whales in particular, during this time of year. These results demonstrate that shore-based surveys can provide an alternative means of surveying an area where use of other research platforms are impractical or cost prohibitive.

Whales and dolphins use sound for different functions including echolocation and social communication, and thus changes in sound production patterns are a likely component of any behavioral response to anthropogenic sounds such as military mid-frequency sonar (MFA). To simultaneously log whale and dolphin movements, sound production and reception, and anthropogenic sound exposure levels, we used Dtags (Woods Hole Oceanographic Institution) and bioacoustic probes (Greeneridge Sciences). Tags were deployed on wild, free-ranging cetaceans in Southern California waters. Tagged animals were then exposed to simulated MFA or, as a control, pseudo-random noise (PRN). In total, the August-September 2010 SoCal10 behavioral response study included 28 playbacks: 19 to blue whales (11 MFA, 8 PRN), 5 to fin whales (3 MFA, 2 PRN), 2 to a single sperm whale (1 MFA, 1 PRN), 1 to a Risso’s dolphin (MFA), and 1 to a Cuvier’s beaked whale (MFA). For this analysis we focus first on baleen whale call production and reception rates (particularly blue whale D calls and variable calls) in relation to sound exposure level, dive behavior, and lunge feeding rates. We then examine echolocation-based foraging behavior and social call production by the toothed whales as a function of sound exposure level. This rich dataset, including multiple cetacean species of conservation concern, provides insight into the wide potential range of responses to sound, and the dependence of those responses on ecological, social and behavioral context. Investigations like SoCal10 can help guide inferences for related topics, such as assessment of population effects of anthropogenic noise.

Autonomous acoustic recorders are effective for investigating the distribution, occurrence, and acoustic behaviors of a variety of marine mammals in remote and deep-water locations. Nine Marine Autonomous Recording Units (MARU’s) were deployed in a rectangular array at a site coinciding with the United States (U.S.) Navy’s planned Undersea Warfare Training Range (USWTR) approximately 60-150 kilometers offshore Jacksonville, FL. All 9 units were deployed for 26 days in fall (13 September to 8 October) and 37 days in winter (3 December to 8 January) 2009-2010 at shallow, mid-depth, and deep sites (45, 183, 305 meters). The timing of the deployments allowed recordings of cetacean vocalizations and sonar activity to be made before, during, and after two U.S. Navy training exercises. The goal of this study was to characterize minke whale vocal activity in relation to U.S. Navy mid-frequency sonar signals. Data were reviewed in detail using the MATLAB program Triton (Wiggins 2007). Event logs were created for each day at every site. Custom-written MATLAB scripts were used to calculate the probability of minke whale vocalization events occurring in the presence and in the absence of mid-frequency sonar. Minke whale vocalization events were completely absent in the fall deployment period, but occurred almost continuously during the winter deployment, indicating a strong seasonal pattern of occurrence. Minke whale vocalizations were detected most frequently at deep-water sites, but only at low levels (

Visually validated towed hydrophone array recordings made in the presence of four killer whale communities (northern and southern residents, offshores, and west coast transients) were collected during the Pacific Orca Distribution Surveys (PODS) conducted by the Northwest Fisheries Science Center in the winters of 2006-2009, 2012, 2013, and 2015. Killer whale communities are known to exhibit differences in their prey preferences, genetic structure, and acoustic call repertoire, but little is known about differences in echolocation clicks. Over 20,000 echolocation clicks were measured from 49 independent killer whale acoustic encounters that were recorded during these cruises to compare signal parameters between communities. Echolocation click parameters were measured automatically using tools available in PAMGuard software. Results of pairwise comparisons indicated that duration, center frequency, peak frequency, sweep rate, number of zero crossings, and inter-click interval were significantly different (Kolmogorov-Smirnov test, p

A combination of visual line-transect survey and photo-identification methods is being used to gather baseline information on the occurrence, distribution, and density of marine mammals near areas of substantial U.S. Navy activity in Virginia. Forty-seven line-transect surveys were completed in two zones (INSHORE and MINEX) between August 2012 and December 2014, with 5,106 km and 276.5 hours completed on-effort. The majority of sightings were of common bottlenose dolphins (Tursiops truncatus), although humpback whales (Megaptera novaeangliae) and shortbeaked common dolphins (Delphinus delphis) were also sighted. Conventional line-transect analysis of bottlenose dolphin sightings showed both spatial and seasonal variation in density (D) and abundance (N), with greatest abundance in the MINEX zone during fall months, followed closely by the INSHORE zone during fall months. Densities in the INSHORE zone were calculated as 4.12 individuals per km2 (abundance [N] =1,279) in fall, 0.45 (N=138) in winter, 1.02 (N=316) in spring, and 2.86 (N=887) in summer. Densities in the MINEX zone were calculated as 2.23 individuals per km2 (N=1,333) in fall, 0.06 (N=35) in winter, 0.24 (N=145) in spring, and 1.19 (N=709) in summer. Nineteen photo-ID surveys were completed, and a catalog was created using photos taken during both dedicated photo-ID and line-transect surveys. Approximately 500 unique individuals were added to the catalog from the first year of survey efforts. Re-sighting rates across surveys were low, indicating an open population, with short-term visits to the area. Most re-sightings were less than 3 months and 21 km apart, and between-year re-sightings showed seasonal occurrence in the study area-with animals not sighted for the majority of the year then returning the following year in the same season. Further analyses are needed to better define the distribution patterns of the dolphins utilizing the area, and the extent of overlap with bottlenose dolphin stocks along the coast.

Measurements of underwater noise from pile driving were collected in San Diego Bay during a marine construction project to inform placement of marine mammal observers, and adhere to Incidental Harassment Authorization (IHA) requirements. This work presents the modeling of Zones of Influence (ZOIs) for pile driving noise as well as results from ambient noise monitoring. Results from real-time monitoring showed good agreement with the modeling isopleths associated with the 190 dB and 180 dB isopleths (rms level, dB re 1 µPa) that define Level A injury thresholds for pinnipeds and cetaceans, respectively. Ambient noise measurements were also collected in the bay; we evaluate the L10, L50 and L90 exceedance levels (where Lx means these values were exceeded x% of the time) from a regulatory standpoint.

A three month visual and acoustic line-transect survey of a large (584,800 km2) study area centered on the Northern Mariana Islands (MISTCS) was conducted in winter of 2007 (DoN 2007). Line-transect survey and analytical methods are well developed for estimating abundance of marine mammals using visual sighting data. These methods also can be applied to acoustic data when a perpendicular distance from the trackline to the "detection" is obtained. Sperm whales produce distinctive broadband (100 Hz to 25 kHz) echolocation signals. Although sperm whales typically produce "regular" clicks, males are known to produce high amplitude clicks with slow inter-click intervals (i.e. "slow" clicks). Previous studies have used a combination of acoustic and visual survey methods to estimate sperm whale densities. The aim of this study was to use acoustic localizations of sperm whales to estimate a detection function for the MISTCS study area. Sperm whale acoustic encounters were post-processed using PAMGuard software to obtain "click files" that were then processed using Rainbow Click software (IFAW). Rainbow Click was used to visualize time/bearing and map displays of detected clicks and associated bearing estimates, and mark individual click trains ("events") for each encounter. Target motion analysis methods utilizing a least squares algorithm to calculate perpendicular distances to each "animal/event" were applied using custom MATLAB code that interfaced with Rainbow Click. Next, perpendicular distances and transect length data were imported into the software program Distance (6.0 release 2) to model detection functions. Models were fit for all clicks types combined, regular clicks only, and slow clicks only. Slow and regular click localizations exhibited different shapes in their distribution, likely because slow clicks have higher amplitudes and can be detected over greater ranges than regular clicks. A discussion of these results and comparisons to similar research using acoustic-based line-transect data will be presented.

Sperm whales are highly social cetaceans that live in matrilineal family units and inhabit all ocean basins from the tropics to polar regions. They produce stereotyped patterns of 3 to 40 broadband clicks, termed “codas,” that typically occur within a period of less than 3 seconds. Coda repertoires are unique for different sperm whale social units. These have been referred to as "dialects" and can be assigned to one of several larger social groups termed "vocal clans," which have been used to define sperm whale population structure. Extensive studies of vocal clans have been conducted in the eastern tropical Pacific Ocean (ETP), however little is known about sperm whale coda repertoires in the western Pacific Ocean. Codas can be classified into types according to the number and temporal pattern of the clicks. Rendell and Whitehead (2003) identified five vocal clans across the ETP and south Pacific oceans. The three dominant clans are termed “regular,” “+1” and “short” based on the predominant coda type represented in the repertoire. We reviewed codas recorded from independent sperm whale groups that were acoustically and visually encountered during two marine mammal surveys in the Northern Mariana Islands and Palau regions, conducted in 2007 and 2012 respectively. Using the sperm whale click detector module and event identification modules in the acoustic processing software PAMGuard, we isolated and identified coda inter-click intervals for ten sperm whale groups from the Mariana Islands survey and three groups from the Palau survey. Three bioacousticians classified each coda to type. Codas that were not classified the same by two or more bioacousticians were excluded from further analysis. This qualitative process of identifying coda types resulted in large representation of the "regular" vocal clan. The identification of regular vocal clans within this region has implications for understanding the culturally-linked stock distribution and population structure of sperm whales in this region and across the Pacific Ocean. Several studies have evaluated the relationship between genetic variation and vocal repertoire to inform sperm whale stock management. To better understand the potential relationship between genetics and population structure of sperm whale stocks within the Pacific Ocean basin, we recommend future studies of sperm whales in the western Pacific Ocean that include genetic sampling paired with passive acoustic monitoring.

We deployed 20 Low-Impact Minimally-Percutaneous External-electronics Transmitter (LIMPET) satellite-linked transmitters and dive recorders on short-finned pilot whales (Globicephala macrorhynchus) off Cape Hatteras, NC during the summer of 2014. Our objective was to obtain information on medium-term movement and diving patterns of individual animals to complement existing information on long-term residency patterns derived from photo-identification and shortterm diving behavior from Digital Acoustic Tags. We deployed 14 location-only (SPOT5) tags and six MK 10-A tags, which provided information on depth of dive, as well as location data. We received transmissions and data from these tags for up to 194 days (median=43 days). Tagged individuals ranged from Onslow Bay, NC north to Georges Bank, MA, and east to the New England seamounts. Most tagged individuals showed a very strong affinity for the continental shelf break, but there was wide variation in movement patterns and habitat use at the individual level. Maximum distances from the tagging location ranged from 7 - 1192 km (median=252 km), while cumulative distances traveled spanned 55 - 7564 km (median=2322 km). Despite these long-distance movements, however, we observed a high degree of site fidelity of short-finned pilot whales off Cape Hatteras, with 25 inter-annual and inter-season photographic matches (11%) in a preliminary catalog of 229 individuals. Some individuals have been matched over periods of up to six years. We matched three of the satellite-tagged animals (15%) to our existing photo-identification catalog. One hypothesis for this apparent conundrum is that the shelf break offshore of Cape Hatteras, NC is an important area for this species, to which individuals return frequently. We are conducting additional satellite tagging efforts off Cape Hatteras, NC and continuing to examine photo-identification records and social structure of short-finned pilot whales to further refine patterns of their long-term spatial and habitat use of the species in the Northwest Atlantic.

The U.S. Navy has proposed establishing an Undersea Warfare Training Range (USWTR) in an area between 60 and 150 km off the coast of Jacksonville, Florida. To establish baseline information on the occurrence and distribution of marine mammals in this area we conducted aerial and shipboard line-transect surveys and a passive acoustic monitoring program. Here we report the results of aerial and shipboard line-transect surveys conducted between January 2009 and April 2011. During this period, we flew 42,895 km of aerial tracklines and recorded 477 sightings of ten cetacean species (n=5,736 individuals). Tursiops truncatus was encountered most commonly (202 sightings, n=1,699), followed by Stenella frontalis (184 sightings, n=3,213). Other species observed during aerial surveys include Grampus griseus (n=350), Globicephala macrorhynchus (n=174), Steno acutorostrata (n=13), Eubalaena bredanensis (n=118),Balaenoptera glacialis (n=3), Physeter macrocephalus (n=2), Kogia spp. (n=1), and Megaptera novaeangliae (n=1). In 35 vessel surveys totaling 2,486 km we encountered three cetacean species in 77 sightings (n=576). S. frontalis and T. truncatus were observed most often, followed by G. griseus (n=351, 160, and 43, respectively). T. truncatus was observed throughout the entire survey area, but S. frontalis and S. bredanensis were seen exclusively on the continental shelf. All E. glacialis sightings, including a rare observation of an offshore birth, occurred on the western edge of the survey area. All other species were detected only in pelagic waters. Stenella frontalis, T. truncatus, and G. griseus were observed throughout the year (12, 11, and 9 calendar months, respectively); G. macrorhynchus and S. bredanensis were detected from April to October, and all mysticete species were seen only between December and March. This monitoring program, combining a variety of survey modalities, is providing a rich picture of the cetacean fauna in these poorly studied offshore waters.

A multi-institutional marine protected species monitoring program involving aerial, vessel and acoustic surveillance techniques was implemented at the proposed Undersea Warfare Training Range (USWTR) offshore of Jacksonville, Florida in January 2009. Visual surveys, in conjunction with acoustic sampling methods, have been conducted to investigate cetacean and sea turtle occurrence, distribution and abundance. Through December 2012 a total of 722 aerial tracklines (60687 km) were flown, resulting in 641 cetacean sightings, encompassing 8079 individuals. Tursiops truncatus and Stenella frontalis were the most frequently encountered, followed by Grampus griseus, Globicephala macrorhynchus, Balaenoptera acutorostrata, Steno bredanensis, Eubalaena glacialis, Megaptera novaeangliae, Physeter macrocephalus, and Kogia spp. Cetaceans were encountered 126 times during the 3403 km of vessel surveys, totaling 950 individuals. Sightings consisted of S. frontalis, T. truncatus, G. macrorhynchus, and G. griseus. Across all visual platforms, T. truncatus were encountered throughout the range, whereas S. frontalis, S. bredanensis, and E. glacialis were recorded exclusively in shelf waters. All other species were detected only in pelagic waters. The towed passive acoustic array was deployed during 21 vessel surveys, generating 24.2 hours of recordings, detecting all four sighted species. High frequency acoustic recording packages (HARPs) were deployed at two sites in the study area for long‐term passive acoustic monitoring. The HARP data have been analyzed for diel, seasonal, and interannual trends in cetacean occurrence. Surveys are scheduled to continue in order to asses long‐term habitat usage patterns in the USWTR.

We deployed satellite-linked transmitters and dive recorders on several odontocete species off Cape Hatteras, NC as part of a multi-institutional marine protected species monitoring program, involving vessel, aerial, and acoustic survey methods. Our objective was to obtain information on medium-term movement and diving patterns of individual animals to complement existing information on long-term residency patterns derived from photo-identification and short-term dive records obtained from Digital Acoustic Tags (DTags). We deployed 29 Low-Impact Minimally-Percutaneous Externalelectronics Transmitter (LIMPET) tags on individuals of four species during the summer of 2014: 20 Globicephala macrorhynchus, 5 Tursiops truncatus, 3 Ziphius cavirostris, and 1 Delphinus delphis. Nineteen location-only (SPOT5) tags were deployed, while ten tags provided information on depth of dive, as well as location data (MK 10-A). We received data from these tags for up to 193 days. Tagged individuals ranged from Onslow Bay, NC north to Georges Bank, MA, and east to the New England seamounts. Pilot whales in particular showed a very strong affinity for the continental shelf break, but there was variation in movement patterns at both the species and individual levels. Maximum dive depths were 2,800 m for beaked whales (n=2), 1,104 m for pilot whales (n=4) and 944 m for pelagic bottlenose dolphins (n=2). We either re-sighted or matched five of the tagged animals (17%) to our existing photo-identification catalogs. Our results show both strong habitat affinities for these animals and a high and surprising degree of residency, especially for the beaked whales and bottlenose dolphins. We hope to conduct additional tagging efforts off Cape Hatteras, NC and Jacksonville, FL to further refine patterns of long-term spatial and habitat use of odontocetes in the Northwest Atlantic.

The effects of anthropogenic sound on marine mammal behavior remains poorly understood, particularly with respect to fine-scale movement patterns. We exposed tagged blue whales to simulated navy sonar during the SOCAL10 behavioral response study in Southern California. We used two different high-resolution, suctioncup digital archival tags to examine fine-scale whale movement: DTAGs and Bioacoustic Probes. The Bioacoustic probe, which included a hydrophone, a pressure transducer, and a dual-axis accelerometer, allowed us to estimate speed and pitch. The DTAGs are equipped with stereo hydrophones, a pressure transducer, and three-axis accelerometers and magnetometers. These sensors allowed us to determine fine-scale movement in three dimensions and received levels of sound. Our study included 19 sound exposures, consisting of 11 playbacks of mid-frequency sonar and 8 control playbacks of pseudo-random noise. We analyzed 24 parameters related to dive and body kinematics for each dive before, during and after sound exposure. Statistical models were applied to assess the significance of changes in these parameters in relation to the received sound level and distance from the source to the whale. During some exposures there were increases in speed and changes in ascent behavior as well as an apparent displacement away from the sound source after the onset of exposure. However, no clear responses were seen in these behaviors for other exposures. Given the range of factors that can characterize behavior and the potential for infrequent or subtle reactions, these data highlight the need for sufficient baseline data and a comprehensive understanding of the behavioral (social interactions), ecological (prey distribution), and evolutionary (fight or flight) contexts in which assessments of sound effects are made. Blue whales produce low-frequency calls and have generally not been considered sensitive to mid-frequency sounds, however, the current study indicates they may respond under certain situations.

In 2011 the National Marine Fisheries Service recognized four separate island-associated stocks of common bottlenose dolphins within the main Hawaiian Islands, based on photoidentification studies over a 7-year period (2000-2006) as well as genetic analyses of skin biopsy samples. However, uncertainty remains regarding movements outside of the photoID study areas due to spatial biases in sampling effort, particularly the general restriction of small-boat based sampling efforts to the leeward sides of the islands. Since these earlier studies, we have obtained an additional seven years of photoidentification data (2007-2013) from among all the island areas, and deployed satellite tags on nine individual bottlenose dolphins from three of the four stocks (Kaua‘i/Ni‘ihau, 4islands, Hawai‘i Island). Here we assess movements using photo-ID and satellite tag data to ascertain whether these new data sets support or refute the designation of four islandassociated stocks. The photo-ID catalog spanning 2000-2013 includes 1,130 identifications of 509 distinctive individuals. Earlier analyses documented no movements among island areas; with the larger sample size, movements of one individual from O‘ahu to Moloka‘i, across stock boundaries has been documented, although this individual was not observed associating with the main social cluster documented from the 4island stock. Satellite tagged individuals traveled an average of 1,208 km with average tag attachment durations of 18 days (range 9-34), yet median distance from deployment location was only 21 km (maximum distances from deployment location range = 38.6 to 61.4 km). All tagged individuals remained within their recognized stock boundaries, and individuals used both leeward and windward sides of the islands, suggesting the spatially-biased boat-based efforts sample individuals that use both sides of the islands. Our results support earlier assessments of limited movements among island areas and the existence of multiple island-associated populations of this species in the Hawaiian Archipelago.

SSQ53F sonobuoys provide an expendable acoustic monitoring capability for Navy aircraft and surface vessels. Data is transmitted from the buoy to a receiver system on either platform via selectable VHF frequencies. While this sensor has proven valuable in nonmilitary marine mammal detection and localization scenarios, VHF interference encountered during near shore monitoring often precludes continuous coverage. The use of autonomous recording packages, constructed from expended SSQ-53F hardware and hydrophones would provide a cost effective solution to this challenge. In August of 2010, five recording packages were deployed during a three day visual and acoustic survey onboard the U.S. Naval Academy’s 109’ research vessel. The survey was conducted in support of the monitoring plan for the Virginia Capes (VACAPES) Letter of Authorization under the MMPA. When deployed, the constant shallow omni-directional (CSO) hydrophone output voltage was recorded directly from the sonobuoy’s Electronic Function System (EFS) circuit board at a 96 kHz sampling rate using a MicroTrack II digital recorder. The packages proved successful as numerous Tursiops truncatus vocalizations were detected. Sonobuoy deconstruct, feasibility test methodology, and lessons learned will be presented.

SSQ53F sonobuoys provide a reliable though expendable passive monitoring capability for both aircraft and surface Navy vessels. Acoustic data is transmitted from the buoy to a receiver system on either platform via selectable VHF frequencies. While this sensor has proven valuable in most marine mammal detection and localization applications, monitoring regions with significant VHF interference preclude continuous coverage. The use of GPS tracked, autonomous recording packages, constructed from expended SSQ-53F hardware and hydrophones would best suit this purpose. In August of 2010, five “spar buoy” packages were deployed during a three day visual and acoustic survey onboard the U.S. Naval Academy’s 109 foot research vessel in the Virginia Capes Operating Area. Portions of the survey track were within 3 miles of the Virginia coastline and as expected, VHF interference was encountered. When deployed, the constant shallow omni-directional (CSO) hydrophone output voltage was recorded directly from the sonobuoy’s Electronic Function System (EFS) circuit board at a 96 kHz sampling rate using a MicroTrack II digital recorder. The system proved successful as numerous Tursiops truncatus vocalizations were detected. S onobuoy deconstruct, feasibility test methodology, and lessons learned will be presented.

Navy explosives training events pose a risk to marine mammals and sea turtles. In order to minimize the potential impacts and in support of the monitoring plan for the Virginia Capes (VACAPES) Letter of Authorization under the MMPA, visual and acoustic surveys were conducted during explosive training events conducted in August of 2009, 2010 and 2011. Each year's monitoring plan consists of visual and acoustic surveys onboard the U.S. Naval Academy's 109 foot research vessel one day prior to, during and following the explosive training events. In 2009, visual surveys were conducted and a single hydrophone was deployed as a feasibility study and approximately 20 minutes of acoustic data was collected. I n 2010, visual and acoustic surveys were conducted which included the use of five SSQ53F sonobuoys modified for autonomous use. Approximately 20 hours of acoustic data was collected over three days. The August 2011 monitoring cruise will include visual surveys and will utilize six autonomous hydrophones able to record data locally with a sampling rate of 96 kHz. Methods, preliminary results, and lessons learned will be presented.

Long-term implantable satellite tags provide valuable distribution and behavior information for wide-ranging large whales. Follow-up observations of whales tagged with these telemetry devices are critical in evaluating potential health effects from tagging, but are especially difficult for species with cosmopolitan distributions with the ability to travel 100+ km/day. Sperm whales in the Gulf of Mexico are good subjects for such studies, in that animals can be predictability relocated year-round in areas around bathymetric features and have been tagged over a period of many years. A total of 134 Argos satellite-monitored radio tags were deployed on sperm whales from 2001 to 2013: 94 Telonics ST-15 location-only tags (1.9 cm diameter, 26.3 cm long implantable portion), 20 Wildlife Computers Spot-5 location only tags (2.1 cm diameter, 27.2 cm long implantable portion), and 20 Wildlife Computers MK-10 Advanced Dive Behavior tags (2.6 cm diameter, 24.8 cm long implantable portion). Whales were photographed at the time of tagging for identification and to assess tag application. Follow-up observations were undertaken in subsequent tagging seasons and on dedicated resighting trips. Twenty-nine whales were resighted (some up to four times in multiple years) from 1 day to 10 years after tagging. Fifteen of these had tags still attached and 28 were resighted without tags. Some whales were initially resighted with tags, but without tags on subsequent observations. Swelling occurred at two tag sites. Scars after tag loss consisted of fully re-pigmented divots (1-3 cm deep by 4-8 cm diameter). None of the resighted whales showed signs of emaciation or having other health issues, and their behavior was similar to that of untagged whales. One whale was observed with a new calf one year after tagging. These results indicate that satellite tagging poses little or no observable adverse health effects for sperm whales.

A Time Difference of Arrival (TDOA) method was used to acoustically localize vocalizing Bryde's whales (Balaenoptera brydei) on the Navy's Pacific Missile Range Facility (PMRF) in Hawaii. Over 130 days of data were recorded from 2011- 2015, resulting in over 12 Bryde's tracks. The tracks were analyzed for cue rates, swim patterns, bearing, directivity, speed, and dive depths. In six of the encounters the Bryde's appear to be traveling in fairly constant headings (typically south-southwest or westerly) crossing the range area over distances ranging from 12 to 27 km over time periods of 1.5 to 6 h with estimated swim speeds up to 12 km/h. Vocalizing whales produced acoustic cues every 3-7 minutes while transiting. Although the occurrence of transiting Bryde's whales is relatively low, the tracks can provide valuable information about the habitat use of this offshore region, particularly because both visual surveys and animal tagging is difficult in this area.

A Time Difference of Arrival (TDOA) method was used to acoustically localize singing humpback whales (Megaptera novaeangliae) on the US Navy's Pacific Missile Range Facility (PMRF) in Hawaii. 2090 hours of recorded data were collected during non-training event periods between September and June, 2011-2014. Eighty-one three-dimensional tracks were obtained with one to six tracks occurring on 42 separate days. The minimum detection rate occurred in January 2012 with 0.01 dives per hour of effort, and a maximum detection rate of 0.18 dives per hour of effort occurred in March 2011. Tracks were determined to fall into three behavioral categories - Travel, Localized Dive, and Mill. Metrics including bearing, directivity, speed, and dive depths were measured and compared between behavior categories, as well as across the breeding season. While the mean track bearings were not statistically different across months, the range of bearings was more restricted in December-February (152° - 250°, S-SW) than in March-May (114° - 346°, SE-NNW). Tracks of Travel behavior had the highest mean speed, longest distances, deepest dives, and the most direct path. Localized Dives had the least direct path and occurred over the shortest distances. Most tracks started and finished during the daytime period with some continuing into the night, but no tracks started and ended at night, indicating some diel periodicity to the behavior in this area. This analysis can provide valuable information about the habitat use of an offshore portion of humpback whale breeding grounds and the baseline behavior of humpback whales on a US Navy range.

Prior to this study, very little was known about short-finned pilot whales (Globicephala macrorhynchus; SFPW) in the Marianas. Small-boat surveys were conducted on 152 days in February - September 2010-2014 within the waters surrounding the southernmost islands of the Mariana Archipelago. Photo-identification data from 19 encounters with SFPWs and satellite-tag data from 6 encounters with SFPWs were used to investigate individual associations, movements, and space use. A total of 178 distinctive individuals were used in the analysis. Over half (63%) were photographed more than once across multiple years. A network diagram of cataloged individuals suggests there may be separate social networks within the southern Marianas. Ten location-only (SPOT-240C, Wildlife Computers) and one location-depth (SPLASH-292B, Wildlife Computers) satellite tags were deployed in the summer of 2013 and 2014. Individual kernel densities estimates (kde) were calculated for tagged SFPWs with >30 (2 daily) tag locations during summer (June-August). These kdes were then combined to get a single kde for all tagged SFPWs, as well as for each of the two largest social networks in order to estimate probability density contours to find areas with the highest probability of use (10%), core areas (50%), and home ranges (95%) during summer. The areas with highest probability of use during summer were off the west sides of Guam and Rota with no overlap between the two networks. Overlap occurred in both core areas and home ranges. Satellite tag data indicate occasional distant offshore movements by individuals, up to 417 km from shore, though the median distance from shore (17 km) indicates a greater use of near island waters. The location-depth tag duration was 35 days during which 1,321 dives ≥30 m were recorded. The deepest dive recorded was 1,183 m with a 16 min duration. The longest dive was 24 min to a depth of 512 m.

Goals: Understand species occurrence and distribution. Determine the population structure and abundance of the those species. Study the movements and habitat use of individuals and populations. Methods: Small boat-based and ship-based surveys. Passive acoustic recordings (HARPs & towed array). Photo-ID, biopsy sampling, and satellite tagging.

Long-term recordings from passive acoustic monitoring allow examination of diel, seasonal, and inter-annual variation in the occurrence of vocalizing marine mammals. We used High-frequency Acoustic Recording Packages (HARPs) to determine how odontocete vocal events varied temporally in Onslow Bay, North Carolina from October 2007 to April 2010. The recordings showed Risso’s dolphins, sperm whales, and unidentified delphinids are present throughout the year, with sporadic occurrence of Kogia spp. Risso’s dolphins and sperm whales showed a nocturnal increase in the occurrence of clicks; Kogia spp. showed no significant diel variation in the occurrence of clicks; and unidentified delphinids showed either an increase in vocal events at dawn or at night, depending on the time of year and recording site. From mid-November to January, a pattern of long-duration and clustered vocal events is evident in the latenight, early-morning period at a shallow site along the shelf break. These signals were not seen at a deeper site during the same time period, suggesting that animals are moving toward the shelf break area, are staying in the shallow area for longer periods of time, are composed of larger group sizes, and/or are from a migratory species or stock. In addition, these extended vocal events may be indicative of a behavioral change, such as an increase in foraging. Future studies will focus effort on discriminating vocalizations belonging to unidentified delphinids as the majority of the vocalizations came from this group and could shed light on the species responsible for the dawn increase in vocal events.

A multi-institutional, marine protected species monitoring program, involving aerial, vessel and acoustic surveillance techniques, has been implemented at the proposed Undersea Warfare Training Range (USWTR) offshore of Jacksonville, Florida. This abstract reports on the second year of aerial and vessel visual line-transect and acoustic surveys used to investigate cetacean and sea turtle occurrence, distribution and abundance. During aerial surveys, a total of 269 track‐lines (22,695 km) were completed, the majority of which were flown in low Beaufort Sea State (BSS) conditions (94% in BSS 3 or lower). A total of 3,285 cetaceans were recorded in 286 sightings. Tursiops truncatus and Stenella frontalis were the most frequently encountered, followed by Grampus griseus, Globicephala macrorhynchus, Balaenoptera acutorostrata, Steno bredanensis, Eubalaena glacialis, Megaptera novaeangliae, and  Physeter macrocephalus. On March 20, an E. glacialis birth was observed, an event which has only been witnessed once before. Cetaceans were encountered 46 times during the 18.5 days of vessel surveys. Sightings consisted of S. frontalis, T. truncatus, G. macrorhynchus, and G. griseus. The towed passive acoustic array was deployed during 12 vessel surveys, generating a total of 13.75 hrs of recordings including all four sighted species. Two autonomous high frequency acoustic recording packages (HARPs) were deployed in the study region between March 1‐December 31 for long‐ term passive acoustic monitoring. HARP recordings have been recovered from the seafloor and are being analyzed for diel, seasonal, and interannual trends in cetacean occurrence. Surveys are scheduled to continue through 2012 to provide long‐term habitat usage patterns in the USWTR.

A preliminary analysis of minke whale (Balaenoptera acutorostrata) acoustic behavior using data collected from Marine Acoustic Recording Units moored off Jacksonville, Florida in the fall and winter of 2009-2010 indicated that the duration of detected minke whale pulse trains was negatively influenced by the presence of Mid-Frequency Active Sonar (MFAS) activity. Other possible responses to MFAS include changes in characteristics of vocalizations, and movement away from the study area, which would result in a perceived change in vocal activity. Due to a low sample size, more data were needed to further investigate this potential change in vocal activity. Additional analysis was conducted by examining the occurrence and characteristics of minke whale pulse trains twenty-four hours before, during, and twenty-four hours after sonar activity. Acoustic data used for this analysis were collected in 2010-2012 with four High-frequency Acoustic Recording Packages (HARPs) deployed off of Jacksonville, Florida, Onslow Bay, North Carolina, and Cape Hatteras, North Carolina. Periods of MFAS activity were detected and characterized using custom MATLAB® code (SonarFinder). Of the four datasets analyzed, two contained minke whale pulse trains that occurred before, during, and/or after periods of MFAS activity. Over 120 hours of recordings containing minke whale pulse trains from 49 encounters (a sequence of pulse trains with no more than 30 minutes between calls) were reviewed. Pulse trains were annotated and characterized by pulse train type (slow-down, speed-up, or constant), signal to noise ratio (SNR), and frequency range. Only pulse trains with an SNR of greater than 8dB were further analyzed to measure additional variables, including duration and pulse repetition rate. Our statistical analysis to assess changes in the occurrence and characteristics of minke whale pulse trains in relation to MFAS activity will provide insight into minke whale behavior and help guide the development of mitigation strategies for this species.

We deployed four Advanced Dive Behavior tags on blue whales near Pt. Mugu, California, in August 2014. The tags recorded data at 1 Hz from 3-axis accelerometers, magnetometers, and a pressure sensor (depth), while also recording FastLoc GPS locations. Tag attachment duration ranged from 18.3-20.0 d, recording 1068-2918 dives and 185-2539 GPS locations while attached. Whales foraged near the tagging area for up to seven days before dispersing as far as Ensenada, Mexico, and Cape Mendocino, California. Foraging lunges were detected as peaks in the Minimum Specific Acceleration and Jerk during dives, and foraging effort was summarized by identifying sequences of dives (foraging clusters) with no more than three consecutive non-foraging dives. The median foraging cluster contained 10 dives over 1.6 h bouts (min = 3 dives over 0.4 h; max = 68 dives over 12.3 h). Variability between foraging clusters in terms of median dive depth, duration, and number of lunges per dive likely reflects local prey availability. The number and duration of foraging clusters decreased substantially during more linear travel segments after departure from the tagging area. The area covered by lunge clusters was calculated for two tracks with high numbers of GPS locations (2297 and 2539 locations) to compare the spatial scales of foraging effort. Foraging clusters were generally small (median = 1.2 and 1.5 km2, respectively) and temporally distinct (median = 1.8 h and 2.2 h apart, respectively) for both whales. The two whales were in close proximity (

Bryde’s whales (Balaenoptera brydei/edeni) have been considered an anomalous occurrence in the Southern California Bight (SCB). Thus, they typically have been excluded from species lists associated with SCB management documents. In the last 40 years only two visual sightings of Bryde’s whales were documented in California waters, the last one in 1991 (Carretta et al. 2007). This is despite extensive systematic vessel and aerial surveys and presumed recent recordings of Bryde’s whale vocalizations in the SCB. Bryde’s whales are notoriously difficult to differentiate in the field and from fin (B. physalus) and sei whales (B. borealis), given the subtle differences in physical characteristics. Between August 2006 and September 2010, we photo-documented five sightings of five single Bryde’s whales in the SCB. Two of the five sightings occurred in October 2008 and September 2010 during 33,880 km of aerial surveys. The remaining three sightings occurred during small-vessel surveys that included offshore waters: two in June 2006 and one in September 2010. These sightings combined with other reports of presumed vocalizations suggest that Bryde’s whale numbers may be increasing in the SCB. This may be related to global warming, large-scale oceanographic events (e.g., El Niño and La Niña) and resulting changes in prey availability. However, no clear association pattern was evident between ENSO events and our sightings. The recent sightings reported herein indicate that the Bryde’s whale should be considered as a species present in the SCB and photodocumentation is critical to ascertain species.

Bryde's whales (Balaenoptera brydeij edem) have been considered an anomalous occurrence in the Southern California Bight (SCB). Thus, they typically have been excluded from species lists associated with SCB management documents. In the last 40 years only two visual sightings of Bryde's whales were documented in California waters, the last one in 1991 (Carretta et al. 2008). This is despite extensive systematic vessel and aerial surveys and presumed recent recordings of Bryde's whale vocalizations in the SCB. Bryde's whales are notoriously difficult to differentiate in the field, both from each other and also from fin (B. physa/us) and sei whales (B. borealis), given the subtle differences in physical characteristics. Between August 2006 and September 2010, we photo-documented five sightings of five single Bryde's whales in the SCB. Two of the five sightings occurred in October 2008 and September 2010 during 33,880 km of aerial surveys. The remaining three sightings occurred during small-vessel surveys that included offshore waters: two in June 2006 and one in September 2010. These sightings combined with other reports of presumed vocalizations suggest that Bryde's whale numbers may be increasing in the SCB. This may be related to global warming, large-scale oceanographic events (e.g., El Nino and La Nina) and resulting changes in prey availability. Recent sightings reported herein indicate that the Bryde's whale should be considered as a species present in the SCB and photo-documentation is critical to ascertain species.

The U.S. Navy’s framework for marine mammal monitoring in the Gulf of Alaska will be presented. Regulatory permit drivers, ongoing monitoring and future monitoring through 2015 will be described. Ongoing monitoring in agreement with National Marine Fisheries Service (NMFS) includes deployment of two bottom-mounted highfrequency acoustic recording packages (HARP) from Scripps Institute of Oceanography. These devices were deployed on the shelf (200 m) and slope (1100 m) south of Seward, Alaska, in July of 2011. Data was recovered in May 2012, returned to Scripps for analysis, and the HARPs subsequently redeployed at the same locations for continued recording. Refinements in classification and analysis have benefited greatly from improvements identified from similar Navy-funded monitoring at other locations within the Pacific over the past eight years. A technical report on the Gulf of Alaska HARP analysis including species identification, seasonality, and identification of anthropogenic sounds will be presented by the Navy to NMFS in December 2013, and publically available by early 2013. New monitoring has also begun in 2012. A third Gulf of Alaska HARP was deployed offshore at Pratt Seamount (990 m) in September 2012. This HARP along with the previous two HARPs will have data retrieved in May 2013 for subsequent December 2013 reporting. In addition, the Navy is funding a vesselbased visual line transect survey within the Gulf of Alaska in the spring to summer 2013 time frame. This survey, similar to a Navy-funded one in 2009, will be conducted in association with NMFS to included visual transects, towed and sonobuoy passive acoustics, and where possible marine mammal biopsies and satellite tagging. Results from this survey should be available later in 2013.

The U.S. Navy represented by the Pacific Fleet Environmental Directorate, Chief of Naval Operations Environmental Readiness and Energy, Office of Naval Research, and Naval Postgraduate School, fund significant marine mammal monitoring programs within California. The bulk of this effort occurs within the Southern California Bight. In an endeavor coordinated with the U.S. National Marine Fisheries Service (NMFS) to address specific questions, efforts are underway to deploy a variety of research tools as a collection of focused, collaborative studies. Monitoring methods include research elements designed to collect data in support of region-specific monitoring and also contribute to the overall body of marine mammal knowledge. Research elements include visual surveys from airplanes and vessels, passive acoustic monitoring from bottom-mounted systems, photolD, biopsies, and marine mammal tagging. The framework for monitoring and results from August 2008 to August 2010 will be presented. During this period over 35,570 nautical miles of ocean were visually surveyed representing 2,285 hours of effort. There were 2,714 sightings of an estimated 155,375 marine mammals. Over 29,700 hours of passive acoustic recordings were obtained and are undergoing continued analysis. In addition, 24,000 digital photographs were taken of marine mammals, and 18 hours of digital video taken of various marine mammal behaviors. There were also 139 individual tissue biopsies, and 31 satellite tracking tags attached to various species. Continuing efforts in 2011 will employ many of the same techniques used previously. The Navy's annual monitoring reports for 2009 and 2010 are publically available and posted on NMFS' Office of Protected Resources website.

Melon-headed whales (Peponocephala electra) are found throughout the tropics, primarily in pelagic waters but with some being found near-shore around oceanic islands. This species is considered to be sensitive to sound, with one nearmass stranding event in Hawaiian waters associated with a naval exercise. However, relatively little is known of the acoustic behavior of this species. Here we combine multiple passive acoustic tools, including suction-cup attached acoustic tags (DTAGs) and a broadband recorder, the DMON, to gather baseline, broadband bioacoustic behavior data for melon headed whales. Further, two distinct melon-headed populations are compared: the Kohala resident population (KRP) and the Hawaiian Islands population (HIP). DMONs recorded from a towfish and drifter buoy setup. Three animals were tagged, two from the KRP population (estimated group sizes 280 and 350 ! individuals) and one from the HIP population (estimated group size of 350 individuals). In total, 1096 and 329 whistles have been identified from the KRP and HIP tag recordings, respectively. Analyses included spectral and temporal characteristics of the whistles, variability of these signals and whistle type categorizations. Data suggest variation between melon-headed whale populations in whistle duration (mean: KRP – 0.99 s; HIP – 0.75 s), start frequency (mean: KRP – 5.1 kHz; HIP – 5.8 kHz), end frequency (mean: KRP – 4.8 kHz; HIP – 11.5 kHz), peak frequency (mean: KRP – 5.5 kHz; HIP – 7.6 kHz), and centroid frequency (mean: KRP – 7.7 kHz; HIP – 10.1 kHz). No overlap in whistle type was apparent between or within populations, which suggests that individual animals may produce semi-stereotyped calls. These are the first broadband comparisons of melon-headed whale signals. The whistle characterization differences suggest automatic detection and classification algorithms can be used to identify melon-headed whales in Hawaiian waters.

Climate impact models predict the range expansion of warm water species towards the poles in response to ocean warming. Bryde's whales (Ba/aenoptera edem) are commonly found in tropical and subtropical regions of the Pacific Ocean, but few studies have explored the presence of Bryde's whale at the boundaries of their distribution ranges. Like other baleen whales, Bryde's whales produce distinct low frequency (

During 2008 and 2009, we were able to passive acoustically monitor marine mammals in the presence of U.S. Navy anti-submarine warfare training exercises using mid-frequency tactical sonar. The exercises were conducted in the potential sites of the proposed east coast Undersea Warfare Training Range (USWTR). As part of the monitoring effort for these exercises, up to nine bottom-mounted passive acoustic recorders were deployed in Onslow Bay and Jacksonville USWTR sites. The recorders sampled continuously at 32 kHz and 2 kHz for approximate three weeks. We analyzed these acoustic recordings for marine mammal vocalizations and sonar activity using spectrogram correlation detector. The recordings contain hundreds of odontocete vocalizations, including pilot whales (Globicephala sp.) and sperm whales (Physeter macrocephalus), occurring before during and after the sonar events. A review of a subsample of the acoustic data revealed several instances of unidentified odontocetes apparently mimicking sonar signals with frequency modulated whistles of similar frequencies. Ongoing and future efforts will include deploying the recorders at the Jacksonville site in a tighter configuration and synchronizing them in time to localize vocalizations. This effort will provide insight on the proximity and movement of marine mammals in conjunction with Navy exercises occurring in area. These recorders yield important information about the presence and vocal activity of odontocetes during these naval exercises.

Passive acoustic data collected from Marine Autonomous Recording Units during fall (13 September to 8 October) and winter (3 December to 8 January) 2009-2010 were analyzed for acoustic detections of marine mammals and patterns resulting from these detections. The study site coincided with the United States (U.S.) Navy’s planned Undersea Warfare Training Range (USWTR) located approximately 60-150 kilometers off Jacksonville, Florida. Acoustic data consisted of both 2-kilohertz (kHz) and 32-kHz sample rate recordings. Data were initially reviewed using long-term spectral averages, and then evaluated in greater detail from spectrograms using the MATLAB program Triton (Wiggins 2007). Probability of vocalization event occurrence was calculated for each species relative to sonar events. Species and species groups detected included minke whale, North Atlantic right whale, sei whale, (probable) humpback whale, sperm whale, blackfish, and unidentified delphinids. Results indicated that minke whales were present almost continuously during the winter deployment period. Right whale vocalizations were most concentrated during winter, as expected, but were also detected at deep sites (>300 meters), which was somewhat unexpected. Sperm whales occurred exclusively near the continental shelf break, and showed a strong diel pattern with almost all vocalization events occurring between dawn and dusk. There were less obvious patterns for delphinid vocalization events, perhaps because of the grouping of species. Future efforts will include improving species-specific analysis of delphinids. Blackfish were detected relatively infrequently but were most common at the shallow-water sites. Minke whales showed the strongest relationship between sonar events and vocalizations. The probability of minke whale vocalization events occurring in the presence of sonar activity was much less than in the absence of sonar. The results reported here provide an assessment of marine mammal occurrence and distribution within the U.S. Navy’s planned USWTR and insights on species-specific vocal responses to sonar events.

September to 8 October) and winter (3 December to 8 January) 2009-2010. These data were analyzed for acoustic detections of marine mammals and navy sonar. Patterns of vocalizations, including seasonal and diel trends and effects of sonar activities were characterized. The study site coincided with the United States (U.S.) Navy’s planned Undersea Warfare Training Range (USWTR) located approximately 60‑150 kilometers off Jacksonville, Florida. The probability of vocalization events were calculated for each species relative to sonar events. Results indicated that minke whales were present almost continuously during the winter deployment period. Right whale vocalization events were most concentrated during winter, as expected, but also were detected at deep sites (>500m), which was somewhat unexpected. Sperm whale vocalization events occurred exclusively near the continental shelf break, and showed a strong diel pattern with almost all vocalization events occurring between dusk and dawn. There were less obvious patterns for delphinid vocalization events, possibly because we were not able to identify detections to species, and thus multiple species were grouped into one generic category. Blackfish were detected relatively infrequently but were most common at the shallow-water sites. Minke whales vocalization events had a strong negative relationship with sonar events when data from all sites were combined. These results provide an assessment of marine mammal occurrence and distribution within the U.S. Navy’s planned USWTR and important insights on species specific vocal responses, or lack of, to sonar events.

Satellite tags were applied to 59 gray whales from three stocks: 17 on Eastern gray whales (EGW) in Baja California, Mexico, in 2005; 35 on Pacific Coast Feeding Group gray whales (PCFG) off Oregon and northern California in 2009- 2013; and 7 on Western gray whales (WGW) off Sakhalin Island, Russia, in 2010 and 2011. Tracking periods ranged from 3-408 days. A Bayesian switching state-space model (SSSM) was applied to Argos locations for each whale to create regularized tracks and estimate movement behavior. Migratory- and breeding-area locations, identified by visual inspection and behavioral mode classification from SSSM, were eliminated from the tracks. Local convex-hull utilization distributions were calculated for the remaining locations to determine feeding area home ranges (90% isopleths) and core areas (50% isopleths). EGWs had home ranges in the Bering and Chukchi seas, ranging from 7,066-30,650 km2. Home ranges for PCFG whales extended from northern California to Southeast Alaska and ranged from 81-13,634 km2. WGWs had very small home ranges near Sakhalin Island, ranging from 285-4,937 km2. Home ranges were significantly larger for EGWs than for either PCFG whales or WGWs (Kruskal Wallis p=0.02). Core area sizes ranged from 11-12,934 km2 for all whales and were largest for EGWs and smallest for WGWs; however these differences were not statistically significant (Kruskal Wallis p=0.06). Neither home range nor core area sizes were related to the number of days or number of SSSM locations used in the analyses (linear regressions p-values > 0.20). The differences in home-range sizes suggest differences in quality and/or quantity of food resources encountered by these three stocks and may also be a reflection of stock demographics. These results provide valuable information about high-use feeding areas for gray whales throughout the Pacific and suggest potential differences in sensitivities to changes in feeding-area habitat.

Mine detonation exercises in coastal waters have the potential to disturb, injure or even kill marine mammals occurring in the same area. To address concerns about this possibility at the U.S. Navy’s Virginia Capes (VACAPES) Range Complex, an effort was begun in August 2012 to monitor odontocete activity at the mine exercise (MINEX) training range using passive acoustic methods. The objectives of the project were to establish the daily and seasonal patterns of occurrence of dolphins in the VACAPES MINEX training area, to detect explosions related to MINEX activities, and to determine whether dolphins in the area show evidence of a response to MINEX events. Data from moored recorders were analyzed for the daily presence/absence of dolphins and their acoustic activity was quantified in detail for the period prior, during and after MINEX activities, as well as at various distances from the training site. The results reveal that dolphins exhibit a short-term acoustic response immediately following an explosion event. Acoustic activity increases briefly and then declines substantially. There is also evidence of a decrease in overall acoustic activity lasting several hours following the exercise. Current analyses aim to establish whether the observed response represents a shift in acoustic behavior or a spatial redistribution of the animals.

The naval forces of many countries conduct mine detonation exercises in coastal waters as part of their regular training. These exercises have the potential to disturb, injure or even kill marine mammals occurring in the same area. To address concerns about this possibility at the U.S. Navy’s Virginia Capes (VACAPES) Range Complex, an effort was begun in August 2012 to monitor odontocete activity at the mine exercise (MINEX) training range using passive acoustic methods. The objectives of the project were to establish the daily and seasonal patterns of occurrence of dolphins in the VACAPES MINEX training area, to detect explosions related to MINEX activities, and to determine whether dolphins in the area show evidence of a response to MINEX events. Up to four Ecological Acoustic Recorders programmed to achieve continuous monitoring were deployed and refurbished approximately every two months. The data were analyzed for the daily presence/absence of dolphins and their acoustic activity was quantified in detail for the period prior, during and after MINEX activities, as well as at various distances from the training site. The results indicate that dolphins are present daily in or near the MINEX range, a finding that supplements limited visual survey information due to restricted regular access to the MINEX area. The data also reveal that dolphins exhibit a short-term acoustic response immediately following an explosion event. Acoustic activity increases briefly and then declines substantially. There is also evidence of a decrease in overall acoustic activity lasting several hours following the exercise. Current analyses aim to establish whether the observed response represents a shift in acoustic behavior or a spatial redistribution of the animals. These results underscore the value of long-term monitoring to inform the military on the potential impacts on marine mammal populations from training exercises involving underwater explosions.

The naval forces of many nations conduct mine detonation exercises in coastal waters as part of their regular training. These exercises have the potential to disturb, injure, or even kill marine mammals occurring in the same area. To address concerns about this possibility at the US Navy’s Virginia Capes (VACAPES) Range Complex, an effort was conducted to monitor odontocete activity at the mine exercise (MINEX) training range using passive acoustic methods. The objectives of the project were to document the daily and seasonal patterns of occurrence of dolphins in the VACAPES MINEX training area, to detect explosions related to MINEX activities, and to investigate potential behavioral and acoustic responses of dolphins to MINEX events. Up to four ecological acoustic recorders programmed to achieve continuous monitoring were deployed at various distances from the known “epicenter” of training events and were refurbished approximately every two months. Dolphins were detected near the training area year round, with ~97% of monitored days containing some dolphin acoustic signals. However, there was also clear seasonal variability, with a consistent period of low occurrence or reduced acoustic activity during the winter months.

Mine exercise (MINEX) activities have the potential to injure or kill marine mammals occurring in the same area. In March 2011 three common dolphins (Delphinus delphis) were killed at the Silver Strand Training Complex off San Diego, California during a Navy training exercise using underwater explosives. In response to this incident, an effort was begun in August 2012 to monitor odontocete activity at the Virgina Capes (VACAPES) Range Complex MINEX site using passive acoustic methods as part of the Navy’s Integrated Comprehensive Monitoring Program. The objectives of the project were to establish the daily and seasonal patterns of occurrence of dolphins in the VACAPES MINEX training area, to detect explosions related to MINEX activities, and to determine whether dolphins in the area show evidence of a response to MINEX events. Two Ecological Acoustic Recorders programmed to achieve continuous monitoring were deployed and refurbished approximately every two months. The data were analyzed manually for the daily presence/absence of dolphins and their acoustic activity was quantified in detail for the period prior, during and after MINEX activities, which can occur in the range multiple times per month. The results indicate that dolphins are present daily in or near the MINEX range, a finding that was not anticipated based on vessel survey information. The data also reveal that dolphins exhibit a short-term acoustic response immediately following an explosion event. Acoustic activity increases briefly and then declines substantially. There is also evidence of a decrease in overall acoustic activity lasting several hours following the exercise. However, it is not clear yet whether the response represents a shift in acoustic behavior or a spatial redistribution of animals. These results underscore the value of long-term monitoring to inform the military on the potential impacts on marine mammal populations from training exercises involving underwater explosions.

We conducted a home-range analysis on 23 loggerheads that the Virginia Aquarium has tracked since 2011. Of the 23 - 17 were rehabilitated and six were wild caught. All rehabilitated animals were released in Virginia, 13 were released in the Atlantic Ocean, six from beaches located in Virginia Beach, and five from Chesapeake Bay beaches. Three wild caught loggerheads were captured using a dip net and released approximately 115km offshore of Virginia Beach, VA. Two wild caught turtles were recovered from pound net heads on the Eastern Shore of Virginia and released near their recovery locations. The remaining wild caught turtle was captured in netted swimming enclosure on the James River. We released 12 loggerheads May-June, five July-August, five September-October, and one in November. Location data collection periods ranged from 20 to 299 days. All transmitters were applied to the second and/or third vertebral scutes using Sita Anchor-Fix™ epoxy. We deployed six Sea Mammal Research Unit and eight Wildlife Computers tags. We applied the Movebank (http://www.movebank.org) Douglas filtering algorithm to all records and set the parameters to select the records with the best accuracy within 24 hour time frames. Location points collected in the first 48 hours post-release were removed.

Group behavior and interactions of endangered blue whales (Balaenoptera musculus) have not been systematically studied. We hypothesized that response variables of blue whale sighting rate, group type and cohesion differed by the explanatory variables behavior state, time of day, season, water depth and distance from shore. To address our hypotheses, we flew systematic line transect surveys in southern California and collected focal group data. Chi-square contingency table and G² analyses were used to assess statistical relationships between response and explanatory variables. Observation effort totaled 87,555 km involving 18 (1-week-long) aerial surveys spanning Jan-Dec 2008-2013. Seventy blue whale groups (117 individuals) were seen, ranging in size from 1-6 whales (mean = 1.7, SD = 1.20). Results supported our hypotheses that blue whale group characteristics were influenced by behavior state and spatiotemporal variables. Sighting rates were significantly highest during summer followed by spring, fall and winter (p

Aerial surveys offer an ideal observation platform to document the behavior and group size of dolphin species over a wide range in offshore waters in a short period. Eight aerial surveys were conducted near San Clemente Island off southern California, Oct/Nov 2008, Jun/Jul/Nov 2009 and May/Jul/Sep 2010 to monitor behavior of marine mammal species using line-transect and focal-behavioral circling methods. An estimated 94,867 short-beaked (Delphinus delphis) and long-beaked (D. capensis) common dolphins were observed during 346 separate events. Number of sightings, mean group size and initial group behavior state were recorded and compared by diurnal periods. Daytime observation hours were divided into three periods, following the methods of Bearzi et al. (1999): “morning” (0801-1159)(n = 71 sightings, individuals =22,777), “early afternoon” (1200-1559)(n = 191, individuals = 52,926), and “late afternoon” (1600-1959)(n = 85, individuals = 19,164). Sighting rates were highest in the early afternoon (4.1 indiv/km) followed by late afternoon (3.9 indiv/km) and morning (3.3 indiv/km). Mean group size was highest in the “morning” (321 ± 455.8), followed by “early afternoon” (277 ± 354.5) and “late afternoon” (225.5 ± 276.0). During the “morning”, initial group behavior was most frequently surface-active mill (65%) followed by travel(29%). During the “early afternoon”, travel (36%) occurred most frequently,followed equally by surface-active travel (28%) and surface-active mill (28%).During the “late afternoon”, travel (37%) and surface-active mill (36%) occurred most frequently, followed by surface-active travel (27%). Social and apparent foraging behaviors typically occurred during surface-active behavior states. Results suggest that groups of common dolphins of both species aggregate in larger numbers and are generally more surface-active during the morning than early and late afternoon, potentially corresponding with socializing and foraging strategies. Further data gathering and multivariate analyses are underway to elucidate more specific diurnal trends and behavioral correlations.

Aerial surveys offer an ideal observation platform to document the behavior and group size of dolphin species over a wide range in offshore waters in a short period. Eight aerial surveys were conducted near San Clemente Island off southern California, Oct/ Nov 2008, jun/Jui/Nov 2009 and May/Jui /Sep 2010 to monitor behavior of marine mammal species using line-transect and focal-behavioral circling methods. An estimated 94,867 short-beaked (Delphinus de/phis) and longbeaked (Delphinus capensis) common dolphins were observed during 346 separate events. Number of sightings, mean group size and initial group behavior state were recorded and compared by diurnal periods. Daytime observation hours were divided into three periods, following the methods of Bearzi et al. (1999): "morning" (08:01-11 :59)(n = 71 sightings, individuals= 22,777), "early afternoon" (12:00-15:59)(n = 191, individuals= 52,926), and "late afternoon" (16:00-19:59)(n = 85, individuals= 19,164). Sighting rates were highest in the early afternoon (4.1 indiv/km) followed by late afternoon (3.9 indiv/km) and morning (3.3 indiv/km). Mean group size was highest in the "morning" (321 ± 455.8), followed by "early afternoon" (277 ± 354.5) and "late afternoon" (225.5 ± 276.0). During the "morning", initial group behavior was most frequently surface-active mill (44%) followed by travel (29%) and surface active travel (13%). During the "early afternoon", travel (35%) occurred most frequently, followed by surface-active mill (33%) and surface- active travel (24%). During the "late afternoon", surface-active mill (35%) occurred most frequently, followed by travel (28%) and surface-active travel (27%). Social and apparent foraging behaviors typically occurred during surface-active behavior states. Results suggest that groups of common dolphins of both species aggregate in larger numbers and are generally exhibiting more surface-active mill behavior during the morning than early and late afternoon, potentially corresponding with socializing and foraging strategies. Further data gathering and multivariate analyses are underway to elucidate more specific diurnal trends and behavioral correlations.

We systematically video-documented the behavior of a subsample of Risso's dolphins, short-beaked common dolphins (SBCD) and killer whales in the Southern California Bight (SCB) (2009-20 11) to assess whether the observation aircraft (fixed-wing Partenavia) affected selected behavioral variables .

We video-documented the behavior of Risso’s dolphins, shortbeaked common dolphins (SBCD) and killer whales in the Southern California Bight (SCB) (2008-2012) to assess whether the observation aircraft (fixed-wing Partenavia) affected selected behavioral variables. Focal observations were conducted from the aircraft to examine potential changes in group cohesion (minimum and maximum distance between nearest neighbors in body lengths [BL]) and heading reorientation rate, to the plane circling at altitude ~700, 1000, 1500 and 2000 feet (ft). Dependent parameters were selected because previous studies show they are indicative of disturbance to anthropogenic or natural threatening stimuli. Five focal sessions were analyzed: two Risso’s dolphins, two SBCD, and one killer whale. A total of 67 minutes (min) was spent observing Risso’s dolphins, 65 min SBCD and 29 min killer whales. Focal sessions were pooled by species and data were divided into four plane altitude categories: 1750 ft. Analysis of variance (ANOVA) was used to test the null hypothesis that maximum cohesion and reorientation do not vary significantly based on plane altitude. Results suggest that our small plane circling at radial distance 750-1000 ft and altitude 750-2000 ft did not cause measurable changes in cohesion and reorientation, of the three species (based on small sample size). For cohesion (C) and reorientation (R) no significant effects were found (Risso’s dolphin: p = 0.091 and 0.258; SBC: p = 0.068 and 0.847; killer whale: p = 0.270 and 0.060 [C and R, respectively]). Results suggest that “undisturbed” baseline observations can be made on these species from our aircraft within parameters examined. This is important when using the aircraft to assess baseline marine mammal behavior and potential effects of anthropogenic activities relative to management and conservation needs.

Introgressive hybridization, in which genetic material from one species persists in the genome of another species following hybridization, can result in gene trees that do not match species trees and seriously mislead phylogenetic studies. This is particularly true in studies based solely on mitochondrial DNA, as introgression of maternally-inherited genomes is predicted to occur far more rapidly and persist longer than introgression of nuclear genomes. Introgressive hybridization has long been suspected as a source of taxonomic confusion in the Delphinidae. We detected mitochondrial introgressive hybridization in bottlenose dolphins (Tursiops truncatus) sampled around the southern islands of the Mariana Archipelago, where five out of 15 animals possess haplotypes characteristic of Fraser's dolphins (Lagenodelphis hosei). We used mitochondrial sequence data and genotypes from 14 nuclear microsatellite loci to further examine introgression of Fraser's dolphin DNA into the Mariana Islands population of bottlenose dolphins. We compared the Mariana Islands samples to bottlenose dolphin samples from elsewhere in the western Pacific and the Hawaiian Archipelago and to Fraser's dolphin samples from throughout the Pacific and Indian Oceans to investigate the extent and origin of hybrid ancestry in Mariana Islands bottlenose dolphins. We estimate that the Mariana Islands animals derive approximately 14% of their nuclear ancestry from Fraser's dolphins. The fact that every Mariana Islands sample showed evidence of nuclear introgression, combined with the fact that those exhibiting mitochondrial introgression all share the same Fraser's dolphin haplotype, suggests that there was a single hybridization event far enough in the past to allow Fraser's dolphin nuclear DNA to permeate the population. The Mariana Islands samples exhibited low genetic diversity compared to other bottlenose dolphin populations, suggesting that they represent a small, genetically isolated population.

Introgressive hybridization, in which genetic material from one species persists in the genome of another species following hybridization, can result in gene trees that do not match species trees and seriously mislead phylogenetic studies. This is particularly true in studies based solely on mitochondrial DNA, as introgression of maternally-inherited genomes is predicted to occur far more rapidly and persist longer than introgression of nuclear genomes. Introgressive hybridization has long been suspected as a source of taxonomic confusion in the Delphinidae. We detected mitochondrial introgressive hybridization in bottlenose dolphins (Tursiops truncatus) sampled around the southern islands of the Mariana Archipelago, where five out of 15 animals possess haplotypes characteristic of Fraser's dolphins (Lagenodelphis hosei). We used mitochondrial sequence data and genotypes from 14 nuclear microsatellite loci to further examine introgression of Fraser's dolphin DNA into the Mariana Islands population of bottlenose dolphins. We compared the Mariana Islands samples to bottlenose dolphin samples from elsewhere in the western Pacific and the Hawaiian Archipelago and to Fraser's dolphin samples from throughout the Pacific and Indian Oceans to investigate the extent and origin of hybrid ancestry in Mariana Islands bottlenose dolphins. We estimate that the Mariana Islands animals derive approximately 14% of their nuclear ancestry from Fraser's dolphins. The fact that every Mariana Islands sample showed evidence of nuclear introgression, combined with the fact that those exhibiting mitochondrial introgression all share the same Fraser's dolphin haplotype, suggests that there was a single hybridization event far enough in the past to allow Fraser's dolphin nuclear DNA to permeate the population. The Mariana Islands samples exhibited low genetic diversity compared to other bottlenose dolphin populations, suggesting that they represent a small, genetically isolated population.

Passive acoustic monitoring automated processes for detection, classification, model-based localization and tracking have been utilized for multiple species of baleen whales using recorded data from 47 off-shore, bottom-mounted broadband hydrophones at the Pacific Missile Range Facility, Kauai, Hawaii. Automatically detected baleen whales calls’ start times are compared with model-based localizations start times for determining locations where calls were emitted. Kinematic tracks are generated from localizations when multiple parameters exceed thresholds. The kinematic tracks support the notion of a single individual being tracked when call types, intervals, swim speeds and behaviors match what is known for a species. Localization and tracking capabilities increase knowledge of the species monitored by providing: density estimates based upon counts of animals which call, which are more informative than density of calls, directly measured cue rates of animals which call, species utilization of the various habitats being monitored, and different behavioral states of animals can be inferred. Information derived from kinematic tracks such as swim speeds and animal headings lead to basic behavioral observations such as ‘traveling’ (animals moving through the area at fairly constant headings and speeds) and ‘milling’ (where animals remain in the area for long periods of time with many heading and speed changes). Examples are provided for rarely sighted, but acoustically localized and tracked, minke (Balaenoptera acutorostrata) and Bryde’s (Balaenoptera brydei) whales. Behavioral responses of localized minke whales to Navy training have shown lower densities of calling animals in the area during Navy training compared to other periods of time.

Bryde’s whales (Balaenoptera brydei/edeni) have been considered an anomalous occurrence in the Southern California Bight (SCB). Thus, they typically have been excluded from species lists associated with SCB management documents. In the last 40 years only two visual sightings of Bryde’s whales were documented in California waters, the last one in 1991 (Carretta et al. 2008). This is despite extensive systematic vessel and aerial surveys and presumed recent recordings of Bryde’s whale vocalizations in the SCB. Bryde’s whales are notoriously difficult to differentiate in the field, both from each other and also from fin (B. physalus) and sei whales (B. borealis), given the subtle differences in physical characteristics. Between August 2006 and September 2010, we photo-documented five sightings of five single Bryde’s whales in the SCB. Two of the five sightings occurred in October 2008 and September 2010 during 33,880 km of aerial surveys. The remaining three sightings occurred during small-vessel surveys that included offshore waters: two in June 2006 and one in September 2010. These sightings combined with other reports of presumed vocalizations suggest that Bryde’s whale numbers may be increasing in the SCB. This may be related to global warming, largescale oceanographic events (e.g., El Niño and La Niña) and resulting changes in prey availability. Recent sightings reported herein indicate that the Bryde’s whale should be considered as a species present in the SCB and photo-documentation is critical to ascertain species.

We have been conducting ongoing monthly aerial surveys off Cape Hatteras, NC, USA as part of the US Navy's marine species monitoring program in the Atlantic since 2011. We utilize line transect survey methods and extensively photograph all sightings to confirm species identification. Survey tracklines extend from shallow continental shelf waters, across the shelf break, to deep pelagic waters. From May 2011 through December 2014, 26,131km of trackline were flown, and 9,941 individual cetaceans were documented during 437 encounters. Nineteen species of cetaceans, including three mysticetes (Balaenoptera physalus, B. acutorostrata, Megaptera novaeangliae), five deep-divers (Physeter microcephalus, Kogia spp., Ziphius cavirostris, Mesoplodon europaeus, M. mirus), and eleven delphinids (Tursiops truncatus, Stenella frontalis, S. attenuate, S. coeruleoalba, S. clymene, S. longirostris, Steno bredanensis, Peponocephala electra, Lagenodelphis hosei, Grampus griseus and Globicephala macrorhynchus) were encountered. Similar surveys at the adjacent Onslow Bay, NC site yielded only 257 sightings (4,773 individuals representing nine species) despite nearly two times the survey effort flown (48,698km). At Cape Hatteras, minimum abundance estimates (i.e. uncorrected for availability or perception bias) were generated using spatio-temporal density surface modelling for species with sufficient detections. Predicted monthly abundance of T. truncatus varied between 170 (95% confidence interval; 0 - 17,100) and 3,450 (300 - 8,510). Monthly Stenella spp. abundance varied between 110 (0 - 360) and 1,720 (400 - 5,390). Monthly abundance of G. macrorhynchus varied between 10 (0 - 960) and 1,230 (220 - 4,300). These results demonstrate that the waters off Cape Hatteras support both higher diversity and density of cetaceans than adjacent waters along the US Atlantic coast. This site is included in the area of interest identified in six pending permits for large-scale, commercial seismic surveys. We suggest that the high density and diversity of cetaceans at this site warrants a special degree of concern by the US Bureau of Ocean Energy Management.

From June 2007 to April 2011, dedicated aerial and vessel surveys were conducted in a 1,713 km² area in Onslow Bay, NC, identified as a site alternative for a US Naval sonar training range. The site straddles the shelf-break and incorporates shallow, shelf and deeper, pelagic waters. The surveys were designed to investigate occurrence, density, and distribution of protected marine species. Sixty-seven complete aerial surveys covering 48,674 km, and 67 single track-line vessel surveys covering 5,642 km, were conducted. Tursiops truncatus, the most frequently encountered species, was recorded during every calendar month and observed throughout the range. This species displayed two distinct color patterns; dolphins east of the continental shelf break exhibited a white peduncle and were sighted in larger groups, while animals on the shelf were more uniform in color and were sighted in smaller groups. Stenella frontalis, the second most commonly encountered species, was sighted in 10 of 12 calendar months, and had a distribution restricted to inshore continental shelf waters. Globicephala macrorhynchus, Grampus griseus and Steno bredanensis occurred less frequently and were commonly encountered in summer. Only these five species were recorded during the first 33 months of effort. In the subsequent 14 months four additional species, Delphinus delphis, Balaenoptera physalus, Balaenoptera acutorostrata and Megaptera novaeangliae were observed in winter and spring months. The appearance of two “colder” water species, D. delphis and B. physalus, on the same day raises questions about oceanographic features that influence conditions inside the survey area. Variation in Gulf Stream position, and the presence of warm and/or cold core eddies, likely influences cetacean presence at this site in winter months. On-going efforts will be aimed at establishing the relationship between cetacean occurrence and local oceanographic conditions within this site

In the western North Atlantic, the winter distribution of minke whales (Balaenoptera acutorostrata), and the location of their calving grounds, are poorly known. Mitchell (1991) used rare sightings of adults and calves to suggest that minke whales winter from the West Indies east to Bermuda. Here we report recent survey data that suggest minke whales also utilize offshore waters of the South Atlantic Bight during winter. We conducted monthly aerial and long‐term acoustic surveys at two offshore sites ‐ Onslow Bay, NC and Jacksonville, FL ‐ fom June 2007 to April 2011, and January 2009 to April 2011, respectively. Minke whales were visually detected twice at the Onslow site and nine times at the Jacksonville site, during the months from December to February. Calves were observed a single time at each of the two survey sites. At each site the number of acoustic detections exceeded visual observations; minke whales were acoustically detected from November through April. A review of minke whale sightings (n= 22) made available by the North Atlantic Right Whale Consortium (1980-2010) suggests a similar seasonal and geographical distribution pattern in the mid‐ and southeast Atlantic. Since 1992, all nine recorded strandings of minke whales in the southeast US have been of calves, and seven of these stranded in winter or spring (data provided by NOAA SER). These recent data add to the results of Mitchell (1991) and suggest that the winter migratory and/or calving grounds extend to the offshore waters from North Carolina to Florida.