Squids caught by shrimp trawlers off the coast of Sergipe, northeastern Brazil

ABSTRACT

The objective of this study was to identify the squids caught by shrimp trawlers in Sergipe and to describe their populational structure. Four samples were obtained monthly from commercial trawlers based in Pirambu-Sergipe (May/2015-May/2016). Each squid found was separated, identified, weighed individually (wet weight - WW in g) and had its mantle length (ML; cm) and total length (TL, including tentacles; cm) measured. One specimen of Doryteuthis pleii was captured (23.3 cm ML mature male), as well as 152 specimens of Lolliguncula brevis (1.5˗6.7 cm ML). The linear relation between TL and ML of L. brevis was TL=5.1173+2.6190ML (positive allometry) and the power relation between WW and ML was WW=0.1453ML^2.5353 (negative allometry). For L. brevis, there were two cohorts in the area during the period analyzed. Studies on the biology of cephalopods are scarce in northeastern Brazil, especially considering that these species are present in the bycatch of shrimp fishing and that the global conservation status of L. brevis is data deficient (DD) according to the International Union for Conservation of Nature (IUCN).

Keywords:
Bycatch; Cephalopoda; Doryteuthis pleii; Lolliguncula brevis