Estrutura populacional do camarão sete-barbas Xiphopenaeus kroyeri (HELLER, 1862) na Foz do rio São Francisco, Nordeste do Brasil

Abstract

Xiphopenaeus kroyeri (Heller, 1862) has a wide marine distribution, occurring from North Carolina (EUA) to Rio Grande do Sul (Brazil), being the only Penaeidae found in the Western Atlantic. The species inhabits sandy or muddy ground in shallow waters. It’s an important fishery resource to communities that live on the coast. The population structure analysis of sea-bob shrimp from São Francisco River mouth, Alagoas-Brazil, was the main objective of this study, and specifically the growth rate of the species. Along the research 4267 specimens of Xiphopenaeus kroyeri were collected, from which 47.93% males and 52.07% females, proportion differing from expected (1:1). The total length for males varied from 28.27 to 108.44mm (77.16 ± 0.27) with width of 80.17mm. The female reached higher length, varying from 11.20 to 125.51mm (82.03 ± 0.33) with width of 114.31mm. The average being significantly different (p> 0.0001). The weigh/length rate has showed exponential tendency, with allometric growth pattern. Moreover, the growth curves plotted in this study show that, after 24 months, the individuals from São Francisco River mouth had not reached the total length expected to the species yet, registering inferior values compared to other regions. Recruitment peaks differ from the ones established to the region, being the main peak in August/10 and the secondary in January/10, therefore the legal protection period to the species requires a review. Data evaluated in this study suggest the importance of further research, more specifically to evaluate the sustainability of the Xiphopenaeus kroyeri population, as well as to verify the efficiency of the laws applied to juvenile protection purposes.