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Anthropogenic activities can lead to changes in animal behavior. Predicting population consequences of these behavioral changes requires integrating short-term individual responses into models that forecast population dynamics across multiple generations. This is especially challenging for long-lived animals, because of the different time scales involved. Beaked whales are a group of deep-diving odontocete whales that respond behaviorally when exposed to military mid-frequency active sonar (MFAS), but the effect of these nonlethal responses on beaked whale populations is unknown. Population consequences of aggregate exposure to MFAS was assessed for two beaked whale populations that are regularly present on U.S. Navy training ranges where MFAS is frequently used. Our approach integrates a wide range of data sources, including telemetry data, information on spatial variation in habitat quality, passive acoustic data on the temporal pattern of sonar use and its relationship to beaked whale foraging activity, into an individual-based model with a dynamic bioenergetic module that governs individual life history. The predicted effect of disturbance from MFAS on population abundance ranged between population extinction to a slight increase in population abundance. These effects were driven by the interaction between the temporal pattern of MFAS use, baseline movement patterns, the spatial distribution of prey, the nature of beaked whale behavioral response to MFAS and the top-down impact of whale foraging on prey abundance. Based on these findings, we provide recommendations for monitoring of marine mammal populations and highlight key uncertainties to help guide future directions for assessing population impacts of nonlethal disturbance for these and other long-lived animals.

© The Author(s), 2012. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in PLoS ONE 7 (2012): e42535, doi:10.1371/journal.pone.0042535., Some beaked whale species are susceptible to the detrimental effects of anthropogenic noise. Most studies have concentrated on the effects of military sonar, but other forms of acoustic disturbance (e.g. shipping noise) may disrupt behavior. An experiment involving the exposure of target whale groups to intense vessel-generated noise tested how these exposures influenced the foraging behavior of Blainville’s beaked whales (Mesoplodon densirostris) in the Tongue of the Ocean (Bahamas). A military array of bottom-mounted hydrophones was used to measure the response based upon changes in the spatial and temporal pattern of vocalizations. The archived acoustic data were used to compute metrics of the echolocation-based foraging behavior for 16 targeted groups, 10 groups further away on the range, and 26 nonexposed groups. The duration of foraging bouts was not significantly affected by the exposure. Changes in the hydrophone over which the group was most frequently detected occurred as the animals moved around within a foraging bout, and their number was significantly less the closer the whales were to the sound source. Non-exposed groups also had significantly more changes in the primary hydrophone than exposed groups irrespective of distance. Our results suggested that broadband ship noise caused a significant change in beaked whale behavior up to at least 5.2 kilometers away from the vessel. The observed change could potentially correspond to a restriction in the movement of groups, a period of more directional travel, a reduction in the number of individuals clicking within the group, or a response to changes in prey movement., The research reported here was financially supported by the United States (U.S.) Office of Naval Research (www.onr.navy.mil) grants N00014-07-10988, N00014-07-11023, N00014-08-10990; the U.S. Strategic Environmental Research and Development Program (www.serdp.org) grant SI-1539, the Environmental Readiness Division of the U.S. Navy (http://www.navy.mil/local/n45/), the U.S. Chief of Naval Operations Submarine Warfare Division (Undersea Surveillance), the U.S. National Oceanic and Atmospheric Administration (National Marine Fisheries Service, Office of Science and Technology) (http://www.st.nmfs.noaa.gov/), U.S. National Oceanic and Atmospheric Administration Ocean Acoustics Program (http://www.nmfs.noaa.gov/pr/acoustics/), and the Joint Industry Program on Sound and Marine Life of the International Association of Oil and Gas Producers (www.soundandmarinelife.org).

This article is distributed under the terms of the Creative Commons Public Domain declaration. The definitive version was published in PLoS One 6 (2011): e17009, doi:10.1371/journal.pone.0017009., Beaked whales have mass stranded during some naval sonar exercises, but the cause is unknown. They are difficult to sight but can reliably be detected by listening for echolocation clicks produced during deep foraging dives. Listening for these clicks, we documented Blainville's beaked whales, Mesoplodon densirostris, in a naval underwater range where sonars are in regular use near Andros Island, Bahamas. An array of bottom-mounted hydrophones can detect beaked whales when they click anywhere within the range. We used two complementary methods to investigate behavioral responses of beaked whales to sonar: an opportunistic approach that monitored whale responses to multi-day naval exercises involving tactical mid-frequency sonars, and an experimental approach using playbacks of simulated sonar and control sounds to whales tagged with a device that records sound, movement, and orientation. Here we show that in both exposure conditions beaked whales stopped echolocating during deep foraging dives and moved away. During actual sonar exercises, beaked whales were primarily detected near the periphery of the range, on average 16 km away from the sonar transmissions. Once the exercise stopped, beaked whales gradually filled in the center of the range over 2–3 days. A satellite tagged whale moved outside the range during an exercise, returning over 2–3 days post-exercise. The experimental approach used tags to measure acoustic exposure and behavioral reactions of beaked whales to one controlled exposure each of simulated military sonar, killer whale calls, and band-limited noise. The beaked whales reacted to these three sound playbacks at sound pressure levels below 142 dB re 1 µPa by stopping echolocation followed by unusually long and slow ascents from their foraging dives. The combined results indicate similar disruption of foraging behavior and avoidance by beaked whales in the two different contexts, at exposures well below those used by regulators to define disturbanc, The research reported here was financially supported by the United States (U.S.) Office of Naval Research (www.onr.navy.mil) Grants N00014-07-10988, N00014-07-11023, N00014-08-10990; the U.S. Strategic Environmental Research and Development Program (www.serdp.org) Grant SI-1539, the Environmental Readiness Division of the U.S. Navy (http://www.navy.mil/local/n45/), the U.S. Chief of Naval Operations Submarine Warfare Division (Undersea Surveillance), the U.S. National Oceanic and Atmospheric Administration (National Marine Fisheries Service, Office of Science and Technology) (http://www.st.nmfs.noaa.gov/), U.S. National Oceanic and Atmospheric Administration Ocean Acoustics Program (http://www.nmfs.noaa.gov/pr/acoustics/), and the Joint Industry Program on Sound and Marine Life of the International Association of Oil and Gas Producers (www.soundandmarinelife.org).

Determining the spatial density and distribution of cetacean (whale and dolphin) species is fundamental to understanding their basic biology, and also to monitoring and mitigating the effect of man-made impacts on their populations. However, this task is difficult because most cetacean species occur at low density and over enormous areas, and because they spend relatively little time at the surface where they can be seen using standard, visual surveys. Our primary long-term goal is to develop and test methods for estimating cetacean density based on detecting the sounds cetaceans make underwater, using fixed hydrophones.

Determining the spatial density and distribution of cetacean (whale and dolphin) species is fundamental to understanding their basic biology, and also to monitoring and mitigating the effect of man-made impacts on their populations. However, this task is difficult because most cetacean species occur at low density and over enormous areas, and because they spend relatively little time at the surface where they can be seen using standard, visual surveys. Our primary long-term goal is to develop and test methods for estimating cetacean density based on detecting the sounds cetaceans make underwater, using fixed hydrophones, Prepared in collaboration with the University of St. Andrews (Fife, Scotland), Oregon State University (Newport, OR), SPAWAR (San Diego, CA), and Woods Hole Oceanographic Institution (Woods Hole, MA).

Author Posting. © Acoustical Society of America, 2009. This article is posted here by permission of Acoustical Society of America for personal use, not for redistribution. The definitive version was published in Journal of the Acoustical Society of America 125 (2009): 1982-1994, doi:10.1121/1.3089590., Methods are developed for estimating the size/density of cetacean populations using data from a set of fixed passive acoustic sensors. The methods convert the number of detected acoustic cues into animal density by accounting for (i) the probability of detecting cues, (ii) the rate at which animals produce cues, and (iii) the proportion of false positive detections. Additional information is often required for estimation of these quantities, for example, from an acoustic tag applied to a sample of animals. Methods are illustrated with a case study: estimation of Blainville's beaked whale density over a 6 day period in spring 2005, using an 82 hydrophone wide-baseline array located in the Tongue of the Ocean, Bahamas. To estimate the required quantities, additional data are used from digital acoustic tags, attached to five whales over 21 deep dives, where cues recorded on some of the dives are associated with those received on the fixed hydrophones. Estimated density was 25.3 or 22.5 animals/1000 km2, depending on assumptions about false positive detections, with 95% confidence intervals 17.3–36.9 and 15.4–32.9. These methods are potentially applicable to a wide variety of marine and terrestrial species that are hard to survey using conventional visual methods., This work was funded by two partners under the National Oceanographic Partnership Program: the Ocean Acoustics Program of the US National Marine Fisheries Service, Office of Protected Resources, and the International Association of Oil and Gas Producers Joint Industry Programme on Exploration and Production Sound and Marine Life.

The vocal behavior of Blainville's beaked whale (Mesoplodon densirostris) was measured using the bottom-mounted hydrophones of the Atlantic Undersea Test and Evaluation Center (AUTEC) in the Bahamas. The statistics for the vocal durations and gaps within these vocal periods were measured over multiple deep foraging dives. The sizes of foraging groups of M. densirostris were estimated from the dive vocalization durations by applying click rate and detection ratio statistics derived from Woods Hole Oceanographic Institution (WHOI) Digital recording Tags (DTags) to visually verified data collected on the AUTEC range., Performed in collaboration with Woods Hole Oceanographic Institution (WHOI), Woods Hole, MA. and the University of Rhode Island, Narragansett, RI. Published in Canadian Acoustics, v36 n1 p166-173, 2008.

Click data from a tagged Mesoplodon densirostris was compared with broadband acoustic recordings from an 82 hydrophone wide-baseline array located in the Tongue of the Ocean, Bahamas. Two detectors, an Fast Fourier Transform (FFT) based detector and matched filter, were evaluated in white noise and with the acoustic recordings from the array for performance detecting M. densirostris clicks. The matched filter performed the best, allowing 92% of the tagged animal's clicks to be detected on at least one hydrophone. Time-Difference-of-Arrivals (TDOAs) between the DTag and the surrounding hydrophones were computed. These TDOAs were used to compute a three-dimensional hyperbolic localization track of the tagged animal. A maximum detection range of 6500 m from the tagged animal to the recording hydrophone was observed. Offset aspect angles were determined from the DTag heading information and the bearing to the receiving hydrophone. Clicks within plus or minus 30 degrees were detected at the farthest ranges, while clicks were detected at all off-set angles at closer ranges., Prepared in collaboration with Woods Hole Oceanographic Institute, Woods Hole, MA and University of Rhode Island, Narragansett, RI. Published in Canandian Acoustics, v36 n1 p60-66, Oct 2008. The original document contains color images. All DTIC reproductions will be in black and white.

Determining the density and distribution of cetacean (whale and dolphin) species is fundamental to understanding their basic biology, and also to monitoring and mitigating the effect of man-made impacts on their populations. However, this task is difficult because most cetacean species occur at low density and over enormous areas, and because they spend relatively little time at the surface where they can be seen using standard, visual surveys. Our primary long-term goal is to develop and test methods for estimating cetacean density based on detecting the sounds cetaceans make underwater, using fixed hydrophones. There are many potential configurations of such devices, so an important second goal (not addressed in this work) is to determine which configurations are best for each of a common suite of monitoring scenarios., Sponsored in part by National Fish and Wildlife Foundation (NFWF) Grant no. 2007-0145-002. Prepared in collaboration with the Naval Underwater Warfare Center, Newport, RI; the Cooperative Institute for Marine Resources Studies (CIMRS), Oregon State University, Newport, OR; Space and Naval Warfare Systems Command, San Diego, CA and the Biology Department, Woods Hole Oceanographic Institution, Woods Hole, MA.

Determining the density and distribution of cetacean species is fundamental to understanding their basic biology, and also to monitoring and mitigating the effect of man-made impacts on their populations. However, this task is difficult because most cetacean species occur at low density and over enormous areas, and because they spend relatively little time at the surface where they can be seen using standard, visual surveys. Our primary long-term goal is to develop and test methods for estimating cetacean density based on detecting the sounds cetaceans make underwater, using fixed hydrophones. There are many potential configurations of such devices, so if it does prove possible to estimate density reliably using passive acoustics, an important second goal (not addressed in this work) is to determine which configuration is best for each of a common suite of monitoring scenarios., Prepared in collaboration with University of St. Andrews, Fife, Scotland, under grant no. NFWF-2007-0145-002. Prepared in cooperation with SPAWAR Systems Center, San Diego, CA. Prepared in collaboration with CIMRS, Newport, RI, and Woods Hole Oceanographic Institution, Woods Hole, MA. The original document contains color images.

Navy sonar has recently been associated with a number of marine mammal stranding events. Beaked whales have been the predominant species involved in a number of these strandings. Monitoring and mitigating the effects of anthropogenic noise on marine mammals are active areas of research. Key to both monitoring and mitigation is the ability to automatically detect and classify the animals, especially beaked whales. This paper presents a novel support vector machine based methodology for automated species level classification of small odontocetes. To date, the algorithm presented has been trained to differentiate the click vocalizations of Blainville's beaked whales (Mesoplodon densirostris) from the clicks produced by delphinids and from man-made sounds. The automated classification capability compliments the detection and tracking tools already developed through ONR funding for the monitoring and localization of whales at the Atlantic Undersea Test and Evaluation Center, Andros Island, Bahamas., See also ADM002006. Published in the Proceedings of the MTS/IEEE OCEANS 2006 Boston Conference and Exhibition held in Boston, MA on September 15-21, 2006. The original document contains color images.

May also be cited as: WHOI-00-02, Calls of blue whales (Balaenoptera musculus), fin whales (Balaenoptera physalus), and humpback whales (Megaptera novaeangliae) were identified in the data from U.S. Navy Sound Surveilance System (SOSUS) and other hydrophone arrays. These data on calling whales from November 1995 through July 1999 have been listed here for four offshore, deep-water Regions along continental margins of the North and Northeast Pacific. The occurrence of calling whales was monitored during two-day periods each week. Call data recorded from each array identified species, call occurrence, variation, received beam, and relative numbers of calling whales. This allowed assessment of seasonal distribution of calls for the different species, and provided locations for sources received at multiple arrays. Blue whale tonal sounds were distributed widely, received most in the NW Region, with a peak in occurrence in the fall. Fin whale "20-Hz" repetitive pulse sequences were received from whales grouped in local areas in all Regions, with a peak in occurrence in midwinter. Humpback songs were received from December through May particularly in the SE Region. The offshore listening systems allowed basin-wide monitoring of the seasonal distribution of these callng whales., Funding was provided by the Office Naval Research under Grant No. N00014-96-1-1130, SERDP and CNO N45.

Calls of killer whales, Orcinus orca, were analyzed using computed sound features to classify sound patterns and identify call similarties. Calls were classified and separated according to the podfamily group within clans identified previously by John Ford (U. BC) in the Vancouver whale populations. Acoustic characteristics of the same call type from different individuals were extremely similar, so that discriminating these different sounds was the goal. The WHOI AcouStat program and associated database systems were used to define numerical statistics for each call, and then, these were compared to sort and classify the sounds. The results were in agreement with Ford's descriptions of the calls derived from visual inspection of sound spectrograms of calls. The classification analyses demonstrated that although specific shared calls from different killer whales were much alike, they could be sorted by the pod/subpod of the whales producing the calls. A typical analysis, for example, of the N4 call from Clan A (Vancouver, BC), classified 97% of the calls correctly according to the pod/family of the whales producing the calls. Remaining calls were variant, and likely a result of individual differences in call sounds. Similar classification analysis were tested on unsorted, unalyzed recordings from different populations of whales, and these too could be distinguished, with 98.5% correct separation of the calls.

Calls of killer whales, Orcinus Orca, were analyzed using computed sound features to classify sound patterns and identify call similarities. Calls were classified and separated according to the pod/family group within clans identified previously by John Ford (U. BC) in the Vancouver whale populations. Acoustic characteristics of the same call type from different individuals were extremely similar, so that discriminating these different sounds was the goal. The WHOl AcouStat program and associated database systems were used to define numerical statistics for each call, and then, these were compared to sort and classify the sounds.