GROWTH AND RECRUITMENT OF THE ATLANTIC SEABOB SHRIMP, XIPHOPENAEUS KROYERI (HELLER, 1862) (DECAPODA, PENAEIDAE), ON THE COAST OF RIO DE JANEIRO, SOUTHEASTERN BRAZIL

摘要

The objective of this study was to analyse the population growth of the Atlantic seabob shrimp, Xiphopenaeus kroyeri (Heller, 1862) and to establish its recruitment period in the northern part of the State of Rio de Janeiro, southeastern Brazil. Monthly samples of the species were collected over four years (2005-06, 2006-07, 2008-09, and 2009-10) through local artisanal fishery. The size of males and females varied from 25.0 to 134.0 mm and33.0 to 146.0 mm in total length, 6.0 to 30.0 mm and 5.0 to 33.0 mm in carapace length,and 0.3 to 13.8 g and 0.2 to 17.4 g in weight, respectively. The total weight-length relationship was adjusted with the equations W = 0.000008TL~(2.9038) (R~2 = 0.9446) (males) and W = 0.000002TL~(3.1719) (R~2 = 0.9499) (females). The Von Bertalanffy growth function TL_t = TL_(infinity)[l — exp~k(t-t_0)] was applied to the data, and the average asymptotic lengths [TL_(infinity)] and growth rates (k) were 134.4 ± 6.2 mm and 1.93 ± 0.3 mm for males, and 148.8 ± 3.6 mm and 1.65 ± 0.05 mm for females.The species' average longevity was 2.5 years for males and 2.8 years for females. Males are considered mature when their reach a total length of 66.0 mm and a carapace length of 12.0 mm, while females mature with 109.0 mm total length and 22.0 mm carapace length. In general, the species' recruitment occurred from June to August and from January to May, which partially supports the current legislation to maintain this fishery resource in the region.