Behavior of estuarine dolphin, Sotalia guianensis (Van Beneden) (Cetacea, Delphinidae) in the presence of tourist boats in Pipa Beach, Rio Grande do Norte, Brazil.

The ever-increasing tourist industry has extended to the aquatic environments, thus making the aquatic mammals Susceptible to interactions with humans. Dolphin watching tourism has developed to a great extent in the Pipa Beach, Rio Grande do Norte, consequently the number of dolphin-watching boats operating in this area has increased. In the present Study the behavioral alterations of Sotalia guianensis (Van Beneden, 1864) caused by the presence of these boats were verified. Behavioral registers of S. guianensis were compiled from a fixed point on the cliffs close to the study area. The observations were effected when there were no boats, in the presence of boats and after the departure of boats. The results show that type of approach by the dolphin watching boats had a major influence on the behavior of the dolphins, especially so in the groups with calves. The short term impacts were rather discrete, however, new methods should be applied in order to verify the long term impacts on the dolphins.