@article {57917, title = {Sounds associated with foraging and prey capture in individual fish-eating killer whales, Orcinus orca}, year = {2019}, abstract = {

Foraging behavior in odontocetes is fundamentally tied to the use of sound. Resident-type killer whales use echolocation to locate and capture elusive salmonid prey. In this investigation, acoustic recording tags were suction cup-attached to endangered Southern Resident killer whales to describe their acoustic behavior during different phases of foraging that, along with detections of prey handling sounds (e.g., crunches) and observed predation events, allow confirmation of prey capture. Echolocation click trains were categorized based on the inter-click interval (ICI) according to hypothesized foraging function. Whales produced slow click trains (ICI \>100\ ms) at shallowest depths but over the largest change of depth, fast click trains (10\ ms \< ICI \≤100\ ms) at intermediate depths, and buzz trains (ICI \≤10\ ms) at deepest depths over the smallest depth change. These results align with hypotheses regarding biosonar use to search, pursue and capture prey. Males exhibited a higher probability of producing slow click trains, buzzes and prey handling sounds, indicating higher levels of prey searching and capture to support the energy requirement of their larger body size. These findings identify relevant acoustic indicators of subsurface foraging behaviors of killer whales, enabling investigations of human impacts on sound use and foraging.

}, doi = {10.1121/1.5133388}, url = {http://asa.scitation.org/doi/10.1121/1.5133388}, author = {Marla M. Holt and Hanson, M. Bradley and Emmons, Candice K. and Haas, David K. and Giles, Deborah A. and Hogan, Jeffrey T.} } @book {57373, title = {Deep Representation Learning for Orca Call Type Classification}, year = {2019}, abstract = {

Marine mammals produce a wide variety of vocalizations. There is a growing need for robust automatic classification methods especially in noisy underwater environments in order to access large amounts of bioacoustic signals and to replace tedious and error prone human perceptual classification. In case of the northern resident killer whale (Orcinus orca), echolocation clicks, whistles, and pulsed calls make up its vocal repertoire. Pulsed calls are the most intensively studied type of vocalization. In this study we propose a hybrid call type classification approach outperforming our previous work on supervised call type classification consisting of two components: (1) deep representation learning of killer whale sounds by investigating various autoencoder architectures and data corpora and (2) subsequent supervised training of a ResNet18 call type classifier on a much smaller dataset by using the pre-trained representations. The best semi-supervised trained classification model achieved a test accuracy of 96\% and a mean test accuracy of 94\% outperforming our previous work by 7\% points.

}, keywords = {bioacoustics, call type, classification, Deep learning, Killer whale, Orca, Representation learning}, isbn = {978-3-030-27946-2}, doi = {10.1007/978-3-030-27947-910.1007/978-3-030-27947-9_23}, url = {http://link.springer.com/10.1007/978-3-030-27947-9}, author = {Bergler, Christian and Schmitt, Manuel and Cheng, Rachael Xi and Schr{\"o}ter, Hendrik and Maier, Andreas and Barth, Volker and Weber, Michael and N{\"o}th, Elmar}, editor = {Ek{\v s}tein, Kamil} } @article {53310, title = {Towards the topology of autoencoder of calls versus clicks of marine mammal}, journal = {The Journal of the Acoustical Society of America}, volume = {144}, year = {2018}, month = {Jan-09-2018}, pages = {1777 - 1778}, abstract = {

The goal is to learn the features and the representation adapted for cetacean sound dynamics without any priors. Thus, we develop data driven model to generate voicing and click of cetaceans audio signals. We learn representation and features of stationary or nonstationary emission using neural network from raw audio. We use different types of convolutions (causal, with strides, with dilation [1]), or gradient inversion [2]. Experiments are conducted on various kind of calls of humpback whales from nips4b challenge [3] or Orca whale. We compare the topology for transient encoding on Physeters and Inia g. For each model, we detail the resulting filters and discuss on the topology. We acknowledge Region PACA and NortekMED for Roger\’s Phd grant, \& DGA and R\égion Haut de France for Ferrari\’s Phd grant. [1] Oord, Dieleman, Zen, Simonyan, Vinyals, Graves et al. Wavenet : A generative model for raw audio, arXiv:1609.03499, 2016 [2] Balestriero, Roger, Glotin, Baraniuk, Semi-Supervised Learning via New Deep Network Inversion, arXiv:1711.04313, 2017 [3] Glotin, LeCun, Mallat et al. Proc. 1st wkp on Neural Information Processing for Bioacoustics NIPS4B, joint to NIPS Alberta USA, 2013 http://sabiod.org/nips4b/challenge2.html, http://sabiod.org/NIPS4B2013_book.pdf

}, issn = {0001-4966}, doi = {10.1121/1.5067859}, url = {http://asa.scitation.org/doi/10.1121/1.5067859}, author = {Roger, Vincent and Ferrari, Maxence and Marxer, Ricard and Chamroukhi, Faicel and Glotin, Herv{\'e}} } @article {53290, title = {Antarctic type C killer whale ( Orcinus orca) call repertoire from McMurdo Sound, Ross Sea}, journal = {The Journal of the Acoustical Society of America}, volume = {144}, year = {2018}, month = {Jan-09-2018}, pages = {1978 - 1978}, abstract = {

Killer whales (Orcinus orca) are found in all oceans of the world. In Antarctic waters, five ecotypes have been described, each displaying distinct differences in morphological features, foraging behaviours, habitat and diet preferences, and genetic structure. Acoustic recordings of Type C killer whales were collected between December 2012 and January 2013 in McMurdo Sound, Ross Sea, Antarctica. Spectrograms of acoustic data were examined for characteristic patterns of Type C vocalizations and a call type catalogue was produced. We measured acoustic parameters of each call type for both whistle and burst-pulse sounds and we then compared call features of Type C animals to those of other killer whales described in the Southern Hemisphere. Analysis of calls revealed that Type C killer whales produce a large number of biphonations and complex calls with multiple frequency-modulated and pulsed components. The limited accessibility of Antarctic regions year-round makes passive acoustic monitoring (PAM) a very effective tool to derive information on ecotype-specific distribution and seasonal occurrence. This study provides new information on the call repertoire of Type C killer whales, investigates the potential use of PAM to study Antarctic ecotypes, and also examines utilising call repertoire as a reliable diagnostic tool for identifying sympatric ecotypes in Antarctic waters.

}, issn = {0001-4966}, doi = {10.1121/1.5068635}, url = {http://asa.scitation.org/doi/10.1121/1.5068635}, author = {Wellard, Rebecca and Pitman, Robert and John W. Durban and Erbe, Christine} } @article {53279, title = {Soundscape characteristics in Southern Resident Killer Whale critical habitats}, journal = {The Journal of the Acoustical Society of America}, volume = {144}, year = {2018}, month = {Jan-09-2018}, pages = {1846 - 1846}, abstract = {

The Southern Resident Killer whales (Orcinus orca) (SRKW) are an endangered group of orcas with current range of Pacific North East from California to Northern British Columbia and spend most of the summer months in and around the Salish Sea. This group of mammals feed primarily on fish, are very local, and live in tight-knit family units called pods. July 1 2017 census reported 77 animals; which now has been reduced to 76 by a more recent death. Anthropogenic underwater noise, primarily from commercial and recreational vessels is suspected to have detrimental effects on these whales. Here, we present results from a seven month, continuous sound recording (125 kHz acoustic bandwidth), whale centered study to monitor and interpret different soundscapes in SRKW critical habitats. The six different locations studied have significantly different acoustic transmission characteristics and cover open ocean areas, where natural sound spectral levels are high, to areas where anthropogenic noise-sources dominate. Possible implications of these different characteristics on the ability of the orcas to communicate and find prey are discussed. [Work funded by the Ocean Protection Plan (OPP) of the Government of Canada.]

}, issn = {0001-4966}, doi = {10.1121/1.5068130}, url = {http://asa.scitation.org/doi/10.1121/1.5068130}, author = {Vagle, Svein and O{\textquoteright}Neill, Caitlin and Thornton, Sheila and Yurk, Harald} } @article {47322, title = {Acoustic classification of dolphins in the California Current using whistles, echolocation clicks, and burst pulses}, journal = {Marine Mammal Science}, year = {2016}, month = {Jan-12-2016}, abstract = {

Passive acoustic monitoring of dolphins is limited by our ability to classify calls to species. Significant overlap in call characteristics among many species, combined with a wide range of call types and acoustic behavior, makes classification of calls to species challenging. Here, we introduce BANTER, a compound acoustic classification method for dolphins that utilizes information from all call types produced by dolphins rather than a single call type, as has been typical for acoustic classifiers. Output from the passive acoustic monitoring software, PAMGuard, was used to create independent classifiers for whistles, echolocation clicks, and burst pulses, which were then merged into a final, compound classifier for each species. Classifiers for five species found in the California Current ecosystem were trained and tested using 153 single-species acoustic events recorded during a 4.5 mo combined visual and acoustic shipboard cetacean survey off the west coast of the United States. Correct classification scores for individual species ranged from 71\% to 92\%, with an overall correct classification score of 84\% for all five species. The conceptual framework of this approach easily lends itself to other species and study areas as well as to noncetacean taxa.

}, keywords = {acoustics, burst pulses, classification, delphinids, dolphins, echolocation clicks, whistles}, doi = {10.1111/mms.12381}, url = {http://doi.wiley.com/10.1111/mms.12381}, author = {Rankin, Shannon and Archer, Frederick and Keating, Jennifer L. and Oswald, Julie N. and Oswald, Michael and Curtis, Alex and Barlow, Jay} }