Shark catch characteristics by national longliner fleets in Madagascar

From 2010 to 2014, Malagasy national fleet deployed on average 7 longliners less than 24 meters operating in the eastern part of Madagascar's EEZ. They deploy 800 to 1300 hooks per set and do short cruises of 4 to 7 days to maintain their catch fresh. The main targeted species are tuna and swordfish but some billfish species and sharks are taken as bycatch. The evolution of shark catch by these longliners in recent years (from 2010 to 2014) is presented in this paper. The data have been collected from the catch declarations by the fishing companies. The total fish catch of the longliners is estimated at 1772 tons since 2010 with an average of 443 tons per year. The largest proportion of catches concerns the targeted species, primarily tunas (45%), then billfish (20%). Sharks represented 13% of catches. Note that the trend of total catch is decreasing since 2010, the same for sharks from 85 tons in 2010 to 45 tons in 2014. However, during the last for years, the cacth per unit effort (CPUE) has been globally increased. Principally, more than three shark species have been caught in the Malagasy waters but the shark catch is mainly dominated by the Shortfin mako (Isurus oxyrinchus) with 36% and the Blue shark (Prionace glauca) that represented 20% of the total shark catch over the four years.