Residence patterns, habitat use, range, and some population estimate of the coastal bottlenose dolphin, Tursiops truncatus (Montagu, 1821), were documented in two coastal sites in southern Brazil: Laguna (Santa Catarina) (28º30'S; 48º55'W), and Imbe/Tramandai (Rio Grande do Sul) (29º58'S; 50º07'W). Regular observations were carried out at the Laguna system for 27 months (August 1989 to December 1991). The dolphins were photo-identified using natural permanent marks. Over 4,500 photograps were taken from shore grounds 6 to 14 meters away. Up to 51 dolphins have used the estuaries of Laguna's canal and Imarui-Santo Antonio's lagoon system in 1991. A stable group of nine animals has inhabited the Imbe/Tramandai area for over 13 years. Both sites were considered distinctive geographical communities, with 5.7% interchange within their individuals. In Laguna 88.5% of the individuals were resident and the rest were nonresident. Four cases of movement along the coastline were followed and females were more resident than males.
Tursiops truncatus; bottlenose dolphin; residence patterns; site fidelity; Southern Brazil