Evidence of long range movements of bottlenose dolphins Tursiops truncatus in the coast of Patagonia, Argentina.

SILVANA L. DANS; ROCIO NIETO-VILELA; RAÚL GONZALES; RAÚL GONZALES; MARIANA DEGRATI; MARIANA DEGRATI; ENRIQUE A. CRESPO; ENRIQUE A. CRESPO; GUILLERMO M. SVENDSEN; GUILLERMO M. SVENDSEN; MARIANO A. COSCARELLA; MARIANO A. COSCARELLA; SILVANA L. DANS; ROCIO NIETO-VILELA

Cassino

Workshop; II Workshop sobre la Investigación y Conservación de Tursiops truncatus en el Atlántico Sur Occidental (ASO); 2017

Universidade Federal do Rio Grande

The photo-identification technique has contributed significantly to the knowledge of the small cetacean species. Bottlenose dolphins in Patagonia were among first populations in which this technique was used. There have been suggestions that dorsal fin morphology could help to differentiate subgroups.2. The current information shows that this population may be genetically isolated. During the last 40 years, it has shown evidence of declining, but the causes are unknown. A displacement to other areas has been suggested, but the home range of the individuals is unknown. 3. We examined a database comprising 184 good quality photographs and analysed the captures of individually identified dolphins in San Antonio Bay, Nuevo Gulf and the port of Rawson. 4. During a span of 15 years dolphins were identified in the three localities; accounting individual movements of 450 km. Dorsal fins of both shapes were present in every location. San Antonio Bay was established as an MPA, protecting an area usually used by this dolphins, but our results indicate that they can move southwards long distances, including the southernmost localities where bottlenose dolphins are regularly spotted in the western South Atlant