Growth and reproduction of the Mediterranean mud shrimp Upogebia pusilla (Petagna, 1792) in the central Aegean Sea, Turkey

Abstract

The aim of this study was to determine the growth and reproduction characteristics of Upogebia pusilla in the central Aegean Sea. This species is widely used by the commercial and amateur bait fisheries in Turkey. A total of 1949 U. pusilla individuals were taken from Izmir Bay between April 2014 and March 2015. Their total length ranged between 16.96 and 80.32 mm (6.51 and 26.56 mm CL) with a mean value +/- SE of 52.41 +/- 0.25 mm (17.54 +/- 0.08 mm CL). The female:male ratio was 1:0.99 (P > 0.05) and males can grow larger than females. For all individuals, the equations CL = 0.317 x TL + 0.951 (R-2 = 0.962) and W = 0.015 x TL3.11 (R-2 = 0.978) described the total length-carapace length and total length-total weight relatioships, respectively. The Von Bertalanffy growth equation for females was CLt = 26.08 x (1 - e(-0.487 x (t + 0.0048))) (phi' = 2.52), while for males it was CLt = 29.12 x (1 - e(-0.424 x (t + 0.0053))) (phi' = 2.56). The relationship between the fecundity and the total length was found to be F = 6.654 x 10(-7) x TL(3.9)0 (R-2 = 0.919). Spawning occurred at three different seasons: between February and April, in June, and in August. The relationship between the total length and sexual maturity was found to be PL = Phi x (-11.449 + 0.288 x TL) (R-2 = 0.926) for females, while it was P-L = Phi x (-10.399 + 0.191 x TL) (R-2 = 0.878) for males. First maturity lengths were estimated as 50.11 mm for females and 54.54 mm for males, and the first reproduction age for both sexes was found to be II+.