Whales and ships: pattern use of Bahía Nueva and possible collision risk

ARGÜELLES, B.; COSCARELLA,M.; BERTELLOTTI, M.

Puerto Madryn

Workshop; Southern Right Whale Die-Off and Kelp Gull Management; 2014

International Whalling Comision - Cancillería Argentina

Southern Right Whales (Eubalaena australis) shifted from areas with minimum human disturbance to those with higher levels of human activities close to Patagonian cites, Argentina. Thus, whales are concentrated around harbors and recreational use areas (water sports and whale watching activities), increasing a possible collision risk between whales and ships, especially in Bahía Nueva (Golfo Nuevo) where navigation constraints do not exist. This bay is intensively used by whales, which perform dives longer than 20 min in an area with depths that range from 80 to 120 meters, and also used by ships as a route to enter to Puerto Madryn port, escalating the risk of collision with vessels when whales emerge to breathe. The main goal of this work is to create a navigation risk map considering collisions with whales as a potential risk. During 2013 whale season, line transects where conducted to determine usage patterns of Bahía Nueva by whales and ships. We also recorded whale dive patterns in the route of access to port with a suction cup device containing a time-depth recorder (TDR). A total of five whales were tagged in November 2013. Results suggested that individuals tagged in Golfo Nuevo dived to depths close to 80 meters. An understanding of whale distribution, abundance and diving patterns will be useful for predicting the potential consequences of the human activities on the population. Then, the collision risk evaluation and the resource management are crucial to ensure a whale protection.