Small cetacean captures in Peruvian artisanal fisheries: High despite protective legislation

Abstract

We detail the first direct, at sea monitoring of small cetacean interactions with Peruvian artisanal drift gillnet and longline fisheries. A total of 253 small cetaceans were captured during 66 monitored fishing trips (Gillnet: 46 trips; Longline: 20 trips) from the port of Salaverry, northern Peru (8 o14′S, 78 o59′W) from March 2005 to July 2007. The most commonly captured species were common dolphins ( Delphinus spp.) (47%) , dusky dolphins ( Lagenorhynchus obscurus) (29%), common bottlenose dolphins ( Tursiops truncatus) (13%) and Burmeister’s porpoises ( Phocoena spinipinnis) (6%). An estimated 95% of common dolphin bycatch was of long-beaked common dolphins ( Delphinus capensis). Overall bycatch per unit effort for gillnet vessels (mean ± sd) was estimated to be 0.65 ± 0.41 animals.set −1 (range 0.05–1.50) and overall catch (bycatch and harpoon) was 4.96 ± 3.33 animals.trip −1 (range 0.33–13.33). Based upon total fishing effort for Salaverry we estimated the total annual average small cetacean bycatch by gillnet vessels as 2412 animals.year −1 (95% CI 1092–4303) for 2002–2007. This work indicates that, in at least one Peruvian port, bycatch and harpooning of small cetaceans persist at high levels and on a regular basis, particularly in driftnet vessels, despite the existence since the mid-1990s of national legislation banning the capture of marine mammals and commerce in their products. It is concluded that the coast of Peru is likely still one of the world’s principal areas for concern regarding high small cetacean bycatch and there is clearly an urgent need to increase the geographic scope of observer effort to elucidate the full magnitude of this issue.