Population structure, growth and reproduction of leaping grey mullet (Liza saliens Risso, 1810) in Beymelek Lagoon, Turkey

Abstract

Population structure, growth, length-weight relationship and reproduction characteristics of leaping grey mullet (Liza saliens (Risso, 1810) were investigated in Beymelek Lagoon from February 2006 to January 2007. During the study, a total of 1248 leaping grey mullet were captured by gill-and trammel nets of various mesh sizes. Male to female ratio for leaping grey mullet population in Beymelek Lagoon was 1: 2.71. The ages ranged from 1 to 4 years for males and from 0 to 5 years for females. The growth parameters of the von Bertalanffy equation were: L-infinity = 35.2 cm, K = 0.276 year(-1) and t(0) = -2.893 year for males, L-infinity = 35.9 cm, K = 0.386 year(-1) and t(0) = -1.760 year for females and L-infinity = 39.9 cm, K = 0.271 year(-1) and t(0) = 2.233 year for all individuals. The calculated length-weight equations were W = 0.0061*L-3.124 for males, W = 0.0060*L-3.124 for females and W = 0.0099*L-2.954 for all individuals. The slope (b) values of the length-weight relationship showed that weight of leaping grey mullet in Beymelek Lagoon increased with length in isometric. The mean condition factor for males, females and all specimens were determined as 0.908, 0.900 and 0.897, respectively. According to sex groups, the mean condition factor of males was slightly higher than that of females. The total length at 50% maturity for female leaping grey mullet was determined as 23.3 cm. It was assumed that spawning period for this species was from May to July.