Fishery discards support scavenging seabird populations in many parts of the world, but little is known of this relationship in Brazil. The present study of the coast of Paraná, southern Brazil conducted monthly surveys over twelve months. We observed nine species of scavenging seabirds taking discards, Magnificent Frigatebird Fregata magnificens and Brown Booby Sula leucogaster being the most abundant and frequent. The highest numbers of scavenging seabirds were observed during trawling activities, which provided far more discards at sea than driftnet fishing. During a fishing moratorium, when no use of trawl nets was permitted, numbers of scavenging seabirds at boats were lower. It seems likely that scavenging seabird populations of the Paraná coast benefit from this supplementary food supply, but the extent to which their numbers are affected is unknown.

Consumption by scavenging seabirds of discards from commercial fisheries is a well- known phenomenon that has been described in many parts of the world (Garthe et al. 1996; Hill & Wassenberg 2000; Arcos et al. 2001; Martínez-Abraín et al. 2002; Garthe & Scherp 2003; Giaccardi & Yorio 2004; Yorio & Caille 2004). Fisheries discards can contribute to increases in populations of scavenging seabirds by making available food they could not obtain naturally, since discards are composed mainly of fish from the seabed that are inaccessible to the predominantly surface-feeding scavengers (Walter & Becker 1997; Valeiras 2003; Krul 2004; Yorio & Caille 2004; Weichler et al. 2004).

In Brazil, studies of the interactions between seabirds and fisheries discards are scarce, recent and concentrated in the southeast of the country, and have been related to discard production from relatively large boats with powerful engines (Branco 2001, 2004; Krul 2004; Branco et. al. 2006). Here we present data on seabirds feeding on discards from small boats fishing on the inner shelf off the coast of Paraná State, Brazil.

We are grateful to Robert Furness who kindly revised the English, and to Ana Paula Chiaverini for designing the map. We are grateful to Martin Heubeck and Andy Webb for their substantial contributions to improve our paper. Our thanks to Emygdio Monteiro Filho for his comments on the manuscript. VLC received her master’s scholarship from Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES), Brazil.

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