First record of orca predation on franciscana dolphins (Pontoporia blainvillei) in Argentina

PADULA, ANTONELLA DAIRA; GANA, JOAQUÍN CARLOS MARIO; GIARDINO, GISELA VANINA; DE LEÓN, MARTA CAROLINA; ELISSAMBURU, ANDREA; RODRÍGUEZ, DIEGO; DENUNCIO, PABLO

THE LATIN AMERICAN JOURNAL OF AQUATIC MAMMALS

SOLAMAC

Año: 2022 vol. 17

1676-7497

The killer whale (Orcinus orca) is an apex marine predator that has a cosmopolitan distribution and preys on a wide variety of marine species, including mammals. Although its feeding habits are well-known in Argentine Patagonia, the information available in northern Argentina is scarce. On the other hand, the franciscana dolphin (Pontoporia blainvillei) is a small cetacean endemic to the Southwestern Atlantic Ocean and also the most threatened in the region. Herein the first evidence of a killer whale predation on a franciscana dolphin in northern Argentina is reported. We analysed the stomach content of a stranded animal in Buenos Aires, Argentina. We compared the franciscana dolphin? teeth found in the stomach content to a reference collection, indicating that they belong to a 1-year-old specimen. With this record, a new prey species is added to the killer whale diet in Argentine waters.