Population biology and fishery characteristics of the smoothhound Mustelus schmitti in Anegada Bay, Argentina

COLAUTTI, D. C.; BAIGÚN, C. R. M.; LOPEZ CAZORLA, A.; LLOMPART, F.; MOLINA, J, M.; SUQUELE, P. N.; CALVO, S. A.

FISHERIES RESEARCH

ELSEVIER SCIENCE BV

Año: 2010 vol. 106 p. 351 - 357

0165-7836

The smoothhound Mustelus schmitti is an important and common target shark inhabiting the Southwestern Atlantic coastal system and usually found in shallow waters. Using experimental fishing and artisanal fishing records we assessed seasonal biological and demographic characteristics relating them to fishery and its potential impact on this resource. We found that juvenile are born and then remain in the bay until sexual maturity. Young adults mate in spring and leave the bay in summer. Older adults reach the bay in spring to give birth, mate and return to the open sea in late spring. Such differences suggest that the bay acts as a seasonal nursery and reproductive area. In Anegada Bay this species represents 96 % of the fishery captures carried out in a high seasonal period. The average harvest in the 2003-2008 period was 164 tons, which represented only 2% of total smoothhound Argentinean landings. Since the fishery operates during a narrow temporal window and the fishing effort can be considered low and since only 10% of the individuals smaller than the mean length at first maturity  were retained by gillnets due to their high selectivity, we conclude that the fishery is exploited on a sustainable basis. Future research efforts should be directed to integrate management plans at a broader regional level including recovery of stock segments under heavy fishing pressure in other fishing areas.