The Indian River Lagoon (IRL) is one of the most diverse estuaries in North America, supporting hundreds of species of wildlife, including bottlenose dolphins that live there . HSWRI has a long-term commitment to the conservation of these animals. In fact, the first study of the biology of IRL dolphins began in the 1970s by HSWRI scientists and colleagues. More recently–in 2002–HSWRI launched the first comprehensive and most extensive aerial survey program to determine the distribution and abundance of IRL dolphins. This ongoing long-term study is critical to the management and conservation of these animals, allowing scientists to monitor trends in abundance that are essential to evaluating the impact human induced mortality as well as the impact of catastrophic events. Our results to-date indicate a seasonal fluctuation in abundance and suggests dynamic patterns of habitat use inside and outside of the estuary.
While aerial surveys combined with advanced statistical methods are the most robust ways to estimate dolphin abundance in the IRL (220 km), an examination of small-scale movement patterns and dispersal require a more direct method. HSWRI scientists are currently conducting boat-based surveys that use photo-identification of individuals (by using the unique notches on the dorsal fin) to further evaluate our hypotheses about habitat and movements of these dolphins. These surveys will allow us to estimate abundance and distribution (in a previously unstudied area), and evaluate the life history characteristics and health of individuals. Through ongoing collaborative efforts with colleagues from nearby institutions we will further investigate broader scale patterns of movements and habitat use of IRL dolphins.