Marine debris ingestion by odontocete species from the Southwest Atlantic Ocean: Absence also matter

Abstract

In this paper, we examined the ingestion of large marine debris (1 mm–1010 mm) in 21 odontocete species that were found dead or by-caught in low frequency in southern Brazil (Rio Grande do Sul State) and northern Argentina (Buenos Aires) between 1988 and 2020. Eight percent of the total individuals studied (13 out of 156), representing nine species, had ingested marine debris. Most of items were made of plastics (68 %), and within them, single-use plastic (e.g. plastic bags) were the dominant man-made items. Seven of the nine species that had ingested marine debris have been previously registered ingestion of this pollutant in other areas of their distribution. We also incorporated endemic odontocetes of the Southwest Atlantic Ocean to the list of affected marine organisms: the Burmeister's porpoise Phocoena spinipinnis, and the Lahille's bottlenose dolphin, Tursiops gephyreus.