Composição dos desembarques de tubarões do gênero Rhizoprionodon desembarcados por uma frota artesanal do Ceará

Abstract

The sharpnose sharks, genus Rhizoprionodon, have biological features that makes them more resilient to fishing pressure when compared to other sharks. However, some species of this genus have been recently classified as “vulnerable” to extinction, including Rhizoprionodon acutus, R. longurio and the two species occurring on the coast of Brazil, R. lalandii and R. porosus. In order to characterize population aspects of these last two species, the landings from an artisanal fishing fleet from Ceará, northeastern Brazil, were monitored. This was done in four different periods (I: 1998-1999; II: 2006-2008; III: 2010-2011; and IV: 2018-2020). In total, 269 days of fishery landings were sampled. A total of 1,160 sharpnose sharks were recorded, distributed in R. porosus (n = 523), R. lalandii (n = 44) and unidentified sharpnose sharks, Rhizoprionodon sp. (n = 589). The portion of the R. porosus population captured and landed by the fleet is composed of young and adults (mainly adults). Throughout the periods there was a reduction in the number of individuals landed, however, fishing effort information is needed before inferences can be made about possible species decline.