Accession Number : ADA543000


Title :   The Relationship Among Oceanography, Prey Fields, and Beaked Whale Foraging Habitat in the Tongue of the Ocean


Descriptive Note : Journal article


Corporate Author : NAVAL UNDERSEA WARFARE CENTER DIV NEWPORT RI


Personal Author(s) : Hazen, Elliott L ; Nowacek, Douglas P ; St Laurent, Louis ; Halpin, Patrick N ; Moretti, David J


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a543000.pdf


Report Date : Apr 2011


Pagination or Media Count : 12


Abstract : Beaked whales, specifically Blainville's (Mesoplodon densirostris) and Cuvier's (Ziphius cavirostris), are known to feed in the Tongue of the Ocean, Bahamas. These whales can be reliably detected and often localized within the Atlantic Undersea Test and Evaluation Center (AUTEC) acoustic sensor system. The AUTEC range is a regularly spaced bottom mounted hydrophone array covering 350 sq nm providing a valuable network to record anthropogenic noise and marine mammal vocalizations. Assessments of the potential risks of noise exposure to beaked whales have historically occurred in the absence of information about the physical and biological environments in which these animals are distributed. In the fall of 2008, we used a downward looking 38 kHz SIMRAD EK60 echosounder to measure prey scattering layers concurrent with fine scale turbulence measurements from an autonomous turbulence profiler. Using an 8 km, 4-leaf clover sampling pattern, we completed a total of 7.5 repeat surveys with concurrently measured physical and biological oceanographic parameters, so as to examine the spatiotemporal scales and relationships among turbulence levels, biological scattering layers, and beaked whale foraging activity. We found a strong correlation among increased prey density and ocean vertical structure relative to increased click densities. Understanding the habitats of these whales and their utilization patterns will improve future models of beaked whale habitat as well as allowing more comprehensive assessments of exposure risk to anthropogenic sound.


Descriptors :   *WHALES , *HABITATS , FEEDING , TONGUE OF THE OCEAN , MARINE BIOLOGICAL NOISE , OCEANOGRAPHY , TURBULENCE , REPRINTS , NOISE(SOUND)


Subject Categories : Biological Oceanography


Distribution Statement : APPROVED FOR PUBLIC RELEASE