Data obtained by observers on board of two fishing vessels during six trips carried out between January-April 2010 to catch tuna were analyzed. Thirty-four fishing days were completed and of the 59 trawls performed 37 turned out positive (with tuna catches). The fishing gear consisted of a purse seine net. Exploitation took place within the Argentine-Uruguayan Common Fishing Zone, between 36° S-39° S. The main landings occurred in March and consisted of slender tuna, Allothunnus fallai (57%), followed by albacore, Thunnus alalunga (28.5%), in January and bonito, Sarda sarda (14%), in April. Sea surface temperature ranged 16 °C-19 °C. A total of 25 length frequency samples allowed to measure individuals of the species above mentioned and those of skipjack... |