Gastrointestinal parasites of bottlenose dolphins Tursiops truncatus at the southern extreme of the southwestern Atlantic, with notes on diet composition

ROMERO M. ALEJANDRA; FERNANDEZ MERCEDES; DANS SILVANA LAURA; GARCÍA NÉSTOR ANÍBAL; GONZALES RAUL; CRESPO ENRIQUE ALBERTO

DISEASES OF AQUATIC ORGANISMS

INTER-RESEARCH

Lugar: Oldendorf/Luhe; Año: 2014 p. 61 - 70

0177-5103

ABSTRACT: We surveyed the gastrointestinal tracts of 6 bottlenose dolphins Tursiops truncatusfrom Patagonia to check for helminth parasites and characterize dolphin diet. All dolphins harboredparasites (6477 helminths). We recorded 7 species, including nematodes Anisakis simplexs.l., Pseudoterranova decipiens, acanthocephalans Corynosoma cetaceum, C. australe, and digeneansBraunina cordiformis, Pholeter gastrophilus and Synthesium tursionis. Among the gastrichelminths, the most prevalent species were C. cetaceum and A. simplex while C. australe andS. tursionis inhabited the intestine at low prevalence. This is the first report of C. australe andP. decipiens in bottlenose dolphins. Regarding diet, 5 stomachs contained food remains (consistingof 103 prey items). The most important prey species were Geotria australis and Stromateusbrasiliensis, but their role in parasite transmission is unclear. At the community level, the gastro -intestinal parasite community of T. truncatus was depauperate and strongly overlapped the communitydescribed for pelagic dolphins inhabiting Patagonia, suggesting a strong local influence inshaping helminth communities. Nevertheless, these observations are at odds with the notion thatoceanic cetaceans have comparatively poorer helminth fauna than neritic species such as bottlenosedolphins, due to the lower likelihood of parasite exchange