A feeding association between Wilson's Storm-petrels Oceanites oceanicus (Kuhl, 1820) and Rough-toothed Dolphins Steno bredanensis (G. Cuvier in Lesson, 1828)

Abstract

On 06 October 2012 a pod of Rough-toothed Dolphins Steno bredanensis (Delphinidae) was observed catching and tearing apart several Castin Leatherjacks Oligoplites saliens (Carangidae) near Montão de Trigo Island, northern coast of São Paulo, Brazil. The resulting floating masses of viscera attracted a feeding aggregation of 120-150 Wilson's Storm-petrels Oceanites oceanicus (Hydrobatidae), a transequatorial migrant passing through the area during October. This interspecific association has not been recorded before, although it could be expected given that S. bredanensis feeds on large fish and O. oceanicus is a known scavenger of kills made by cetaceans such as Killer Whales.

Birds of the Alcatrazes archipelago and surrounding waters, São Paulo, southeastern Brazil

“…Nine seen while sailing between Santos and Alcatrazes on 27 April 1993. On 06 October 2012 about 150 were feeding on fish scraps left by a foraging pod of Rough-toothed Dolphins around 23°52'S, 45°44'W (Olmos et al 2013) (Figure 11). A lone bird was also seen close to our boat at 24°17′10″ S, 45°37′52″ W, or 23 km southeast off Alcatrazes, on 06 April 2013.…”