@article {53323, title = {Acoustic monitoring reveals the times and tides of harbor porpoise (Phocoena phocoena) distribution off central Oregon, U.S.A.}, journal = {Marine Mammal Science}, year = {2018}, month = {Jan-10-2020}, abstract = {

Harbor porpoises (Phocoena phocoena) are commonly observed in Oregon\’s nearshore marine environment yet knowledge of their eco- system use and behavior remains limited, generating concerns for potential impacts on this species from future coastal development. Pas- sive acoustic monitoring was used to investigate spatial and temporal variations in the presence and foraging activity of harbor porpoises off the Oregon coast from May through October 2014. Digital monitoring devices (DMONs) were deployed to record acoustic data (320 kHz sam- ple rate) in two neighboring but bathymetrically different locations off the Oregon coast: (1) a site on the 30 m isobath in close proximity (\<50 m) to a rocky reef, and (2) a site on the 60 m isobath in an open sandy environment. Data were analyzed with respect to two dynamic cyclic variables: diel and tidal phase. Porpoise presence at the rocky reef site was aligned with the ebb phase of the tidal forcing, while, har- bor porpoise presence and foraging at the offshore, sandy bottom site was associated with night-time foraging. The spatial and temporal pat- terns identified in this study suggest harbor porpoise habitat use is\ modulated by specific environmental conditions particular to each site that maximize foraging efficiency.

}, keywords = {distribution, foraging behavior, habitat use, harbor porpoise, Oregon, passive acoustics, Phocoena phocoena, temporal patterns}, doi = {10.1111/mms.12537}, url = {http://doi.wiley.com/10.1111/mms.12537}, author = {Holdman, Amanda K. and Haxel, Joseph H. and Klinck, Holger and Torres, Leigh G.} } @article {53231, title = {Diving behavior of Cuvier{\textquoteright}s beaked whales inferred from three-dimensional acoustic localization and tracking using a nested array of drifting hydrophone recorders}, journal = {The Journal of the Acoustical Society of America}, volume = {144}, year = {2018}, month = {Jan-10-2018}, pages = {2030 - 2041}, abstract = {

Echolocation pulses from Cuvier\&$\#$39;s beaked whales are used to track the whales\&$\#$39; three-dimensional diving behavior in the Catalina Basin, California. In 2016, five 2-element vertical hydrophone arrays were suspended from the surface and drifted at \∼100-m depth. Cuvier\&$\#$39;s beaked whale pulses were identified, and vertical detection angles were estimated from time-differences-of-arrival of either direct-path signals received on two hydrophones or direct-path and surface-reflected signals received on the same hydrophone. A Bayesian state-space model is developed to track the diving behavior. The model is fit to these detection angle estimates from at least four of the drifting vertical arrays. Results show that the beaked whales were producing echolocation pulses and are presumed to be foraging at a mean depth of 967\ m (standard deviation = 112\ m), approximately 300\ m above the bottom in this basin. Some whales spent at least some time at or near the bottom. Average swim speed was 1.2\ m s\−1, but swim direction varied during a dive. The average net horizontal speed was 0.6\ m s\−1. Results are similar to those obtained from previous tagging studies of this species. These methods may allow expansion of dive studies to other whale species that are difficult to tag.

}, issn = {0001-4966}, doi = {10.1121/1.5055216}, url = {http://asa.scitation.org/doi/10.1121/1.5055216}, author = {Barlow, Jay and Griffiths, Emily T. and Klinck, Holger} } @article {53029, title = {Description and classification of Indian Ocean humpback dolphin ( Sousa plumbea ) whistles recorded off the Sindhudurg coast of Maharashtra, India}, journal = {Marine Mammal Science}, volume = {34}, year = {2018}, month = {Jan-07-2018}, pages = {755 - 776}, abstract = {

The Indian Ocean humpback dolphin (Sousa plumbea), a common cetacean species in India, has a diverse vocal repertoire, which to date has not been described in detail. This study focused on analyzing their whistle vocalizations. Humpback dolphins were recorded off the Sindhudurg coast of Maharashtra, India, and 2,260 whistles were analyzed for their acoustic characteristics. Whistles spanned a wide frequency range between 2.3 kHz and 33.0 kHz, with durations ranging from 0.01 s to 1.60 s. Whistles were categorized into seven contour classes based on their qualitative prop- erties. A classification and regression tree (CART) analysis was used to quantify vari- ability between the seven contour classes using the measured acoustic features. Based on the CART analysis, frequency gradient, minimum slope, maximum slope, begin- ning and ending slope accounted for most variability between whistle types. CART resulted in an overall classification accuracy of 89.5\%. This study provides a detailed description of acoustic features and qualitative properties of humpback dolphin whis- tles from the northwestern coast of India. Further comparisons of acoustic data from Sousa populations along the Indian coast are necessary to determine possible geo- graphic variations in whistle characteristics and whether the variations are driven by environmental or genetic factors or a combination of both.

}, keywords = {humpback dolphin, India, passive acoustic monitoring, Sousa plumbea, whistles}, doi = {10.1111/mms.v34.310.1111/mms.12479}, url = {http://doi.wiley.com/10.1111/mms.v34.3}, author = {Bopardikar, Isha and Sutaria, Dipani and Sule, Mihir and Jog, Ketki and Patankar, Vardhan and Klinck, Holger} } @article {16152, title = {Using calls as an indicator for Antarctic blue whale occurrence and distribution across the southwest Pacific and southeast Indian Oceans}, journal = {Marine Mammal Science}, volume = {33}, year = {2017}, month = {Jan-01-2017}, pages = {172 - 186}, doi = {10.1111/mms.2017.33.issue-110.1111/mms.12373}, url = {http://doi.wiley.com/10.1111/mms.2017.33.issue-1}, author = {Balcazar, Naysa E. and Klinck, Holger and Nieukirk, Sharon L. and Mellinger, David K. and Klinck, Karolin and Dziak, Robert P. and Rogers, Tracey L.} }