A Note on Cetacean Bycatch in Pelagic Driftnetting off Southern Brazil

Studies on cetacean-fishery interactions in Brazil have increased notably in recent years but data concerning pelagic driftnet operations have remained limited. Information on this kind of fishery has been collected through interviews with fishermen and ship-owners from the ports of Ubatuba (22Q53 'S, 45Q08 'W) and Itajaí/Navegantes (26Q54 'S, 48Q39'W) or through persona1 observation during seven trips conducted in 1995 (I) and 1997 (6) onboard fishing vessels. Boats using driftnets are known to operate from nine localities along the southem Brazilian coast. The fishing area spans from -21QS to 33Q45'S inwaters ranging from 47-3,600m in depth. Fishing effort is higher in spring and summer than in auturnn and winter due to the distribution and availability of target species. The driftnet fleet operating from Ubatuba is composed of about 20 boats, 6-18m long, with 6-8 fishermen per boat; net panels are 50m 1ong and 12-13m in height; number of panels ranges from 67 (3,35Om long net) to 78 (3,900m long net); and stretched mesh sizes vary from 10-4Ocm. In the neighbouring ports of Ltajaí and Navegantes, there are around 90 boats, 13 to 27m in length, with 10-15 men per boat, net panels are 25-120m long and 4.5-27m high; stretched mesh sizes range from 14-4Ocm. The pelagic driftnet fishery in southem Brazil is focused on sharks (families Sphymidae and Carcharinidae). Incidentally caught species include cetaceans, marine turtles and manta rays (Mantidae). Cetacean species captured (and numbers recorded) are Megaptera novaeangliae (unknown), Physeter macrocephalus (4), Kogia simus (1), Globicephala meias (15), genus Delphinus (2), Tursiops truncatus (1), Stenellafrontalis (5), S. longirostris (2-4), S. clymene (1) and S. coeruleoalba (1). The driftnet fishery may be an important cause of cetacean mortality. Therefore a systematic study must be carried out in order to evaluate the impact of this activity on the species that occur in Southem Brazil.