SUMMARY

• Main Authors: Fábio H. V. Hazin, Humberto G. Hazin, Paulo Travassos
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: Fishing Ground; South Atlantic Ocean
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.542.9097; http://www.flyingsharks.eu/literature/iccat/CV060020636.pdf

Although pelagic sharks are caught in a variety of fishing gears in the Atlantic Ocean, pelagic longline fisheries targeting tunas and swordfish account for the majority of their catch. With the widest geographic range among all large sharks, Prionace glauca is the most abundant elasmobranch caught by longline in oceanic areas. It is a common species throughout the Brazilian coast, being frequently caught by the Brazilian longline fishery. Although much less abundant than the blue shark, the shortfin mako, Isurus oxyrinchus, is also a common epipelagic species found in tropical and warm-temperate seas. In the present study, catch and effort data from the Brazilian tuna longline fleet (national and chartered) (53.713 sets), which operates in the western South Atlantic Ocean, from 1980 to 2004 (25 years), were analyzed. Catch per unit of effort, as the number of fish caught per hundred hooks, was used as an indicator of relative abundance. A delta-lognormal GLM analysis was done in order to standardize the CPUE of blue and mako sharks, based on the following factors: year, month, area, target species, moon phase, Sea Surface Temperature (SST), and depth of the fishing ground. A nominal CPUE series was also calculated for the sharks of the genus Carcharhinus (except C. longimanus). Catch and effort data on the bigeye tresher and oceanic whitetip shark, however, proved to be too fragmentary to generate a CPUE series, so only an estimate of total landings was attempted.