Monster Seminar JAM - From photos to feces: studying dolphin population structure
Dr. Kim Parsons, Conservation Biology Division, NOAA Fisheries
Knowledge of the structuring of natural populations is important for understanding population ecology, and for supporting management decisions. However, conventional methods of direct observation often suffer from a lack of resolution, particularly when studying mobile animals in a marine environment. We integrated both molecular genetic markers and direct observational data to examine the social and population structure of bottlenose dolphins (Tursiops truncatus) in the NE Bahamas. Patterns of individual associations in contrasting habitats indicated that environmental pressures affect both dolphin grouping patterns and the role of kinship within these groups. Nonetheless, a prominent feature of the social structure in both habitats was the persistence of stable alliances among maternally related males. At the population level, significant genetic structuring among three regions on Little Bahama Bank, supported the high degree of site fidelity suggested by individual-based photo-identification data, but contrary to the patterns of dispersal common among most mammals, sex-specific patterns of genetic differentiation were indicative of female-biased dispersal. This study provides novel insight into the factors governing the patterns of structuring within populations of highly mobile small cetaceans, and demonstrates the value of integrating both direct (field-based) and indirect (molecular genetic) data in the study of free-ranging animals.
Date and Time:
May 13, 2004,
11:00 am - 12:30 pm