• bottlenose dolphin;
  • Tursiops truncatus;
  • stock structure;
  • residence;
  • migration;
  • transients;
  • photo-identification;
  • video-identification


Residence patterns of inshore bottlenose dolphins (Tursiops truncatus) in the Stono River estuary, Charleston County, South Carolina were investigated as part of a larger effort to better understand stock structure of these dolphins along the east coast of the United States. Eighty-seven small-boat surveys for bottlenose dolphins were conducted from October 1994 through January 1996. Dolphins were sighted during all surveys. Approximately 304 h were spent surveying the study area; 64% (n= 196 h) of this time was spent observing and videotaping dolphins. A catalog, containing 112 individually identified dolphins was compiled. Thirty-two percent (n= 36) of identified dolphins were sighted once, while 28% (n= 31) were sighted five or more times. Nineteen percent (n= 21) of identified dolphins were determined to be year-round residents; eight percent (n= 9) seasonal residents. The majority (64%, n= 72) of identified dolphins were sighted in the study area during a single season or in two consecutive seasons and were classified as transients. This study documents the northernmost known site of a resident bottlenose dolphin community on the east coast of the United States, suggesting a complex bottlenose dolphin stock structure.