Biology and fishery of the freshwater prawn, Macrobrachium acanthurus (Crustacea, Palaemonidae), in the Japaratuba River’s estuary, Sergipe State

Abstract

The freshwater prawn,  Macrobrachium acanthurus , is an important fishing resource of Sergipe State’s coastal  zone, being caught with traps in the Japaratuba River’s estuary. The samplings were taken in the period from January to  December, 2011, adding up to 1,800 individuals, out of which 57.7% were males and 42.3% females. The mean annual  cape length (CL) was 20.1 mm (males) and 15.6 mm (females), both of them with a modal length of 16.0 mm, having the  mean length at first sexual maturity being estimated as 11.9 mm CL. The females were predominant in number in the  period from April do September, which was shown to coincide with the reproduction season and the height of harvest for  that species. The recruitment, as measured through the mean monthly size variation, extended over the continuous range  of October to May. The fishing effort was measured as 100 traps-day, with a corresponding yield of 10.0 kg, and monthly  revenues of US$1,800.00 (harvest’s peak) and US$ 200.00 (low harvest). With the aim of protecting the stock of  M.  acanthurus , this research work has provided valuable information to subsidize its sound management in Sergipe State.