Summary

Description

This project will use a unique set of individual-based data to quantify and model the behavioral ecology of six Department of Defense priority cetacean species in the Bahamas. Data collected through individual photo-identification, molecular genetics, chemical markers (i.e., stable isotope ratios, persistent organic pollutants, fatty acids), satellite telemetry and acoustic recordings will be integrated to characterize the social structure, residency patterns, reproductive biology, foraging ecology and population structuring of key deep-diving cetaceans in the region. These data will be collected in collaboration with Bahamas Marine Mammal Research Organization, Southwest Fisheries Science Center, Alaska Fisheries Science Center, and the NWFSC, and will be used to model the response of these species to naval sounds. In FY11, the NWFSC analyzed 50 biopsy blubber samples of six priority species of whales from the Bahamas for persistent organic pollutants, fatty acids, lipid classes and percent lipid, as well as the corresponding skin samples for stable isotopes of carbon and nitrogen to help describe the foraging habitats, qualitative prey preferences, and feeding stock structure of these whales. Using these previously collected Bahama whale data as a foundation, we will compare the foraging ecology of sperm, pilot, and melon-headed whales with beaked whales inhabiting the same area. Thus, in like-fashion, using a combination of advanced multivariate statistical methods, the patterns of individual fatty acids (FAs) and persistent organic pollutants (POPs) measured in the blubber of the six priority cetacean species, as well as their skin SI ratios, will be used to do the following: (1) Identify assemblages of individual whales that may represent stable feeding groups (both short- and long-term). (2) Test the extent to which each of these species exhibit site fidelity with respect to their foraging habitats (3) Assess the extent of niche overlap among all these whale species within this ecosystem as indicated by perceived differences in their preferred prey. Because very little is currently known about the foraging behavior of these whales, this represents a significant advance in our understanding of the trophic dynamics, population structure, and feeding ecology of all of these whales. Measures concentrations of POPs and fatty acids, total lipid and lipid profiles, and stable isotopes of carbon and nitrogen in tissues of deep-diving cetaceans and their prey.