Determination of some population parameters of freshwater lobster (Astacus leptodactylus Eschscholtz, 1823) in Tatli and Gici lakes from Bafra fish lakes

In this study, determination of the morphometric parameters, meat yield, egg fecundity and biochemical composition of freshwater lobster (Astacus leptodactylus Eschscholtz, 1823), measurement and comparing of environmental parameters were aimed in Tatlı and Gıcı Lakes from Bafra Fish Lakes in Samsun, Turkey. The research was carried out between November 2018 and October 2019 by monthly catching of freshwater lobsters using fyke net at determined stations. While 105 of 242 freshwater lobsters from Tatlı Lake were female and 137 were male, 87 of 216 freshwater lobsters from Gıcı Lake were female and 129 were male and the difference between the sexes was not significant (p>0.05). The average total length and average weight of freshwater lobsters from Tatlı Lake were 10.27±0.09 cm and 33.76±0.88 g, respectively. In Gıcı Lake, the average total length and average weight of freshwater lobsters were 10.44±0.41 cm and 37.15±1.91 g, respectively. A strong positive linear relationship was found between length and weight of freshwater lobsters in Tatlı Lake (r=0.90) and Gıcı Lake (r=0.91). The abdomen of female freshwater lobsters from Tatlı and Gıcı Lakes was wider than male lobsters (p<0.05). However, the claw length and claw width of the male freshwater lobsters were greater (p<0.05). The average number of individual eggs, the average total egg weight, the average unit egg weight and the average egg diameter of the sampled egged lobsters in Tatlı Lake were 241.24±11.94, 3.22±0.17 g, 0.013±0.001 g and 2.61±0.02 mm, respectively. These were 245.38±15.87, 3.03±0.19 g, 0.013±0.001 g and 2.73±0.02 mm for sampled egged lobsters in Gıcı Lake, respectively. While total meat yield of female and male lobsters from Tatlı Lake were 15.27±0.51% and 15.13±0.64%, respectively, total meat yield of female and male lobsters from Gıcı Lake were 15.18±0.59% and 15.51±0.69%, respectively. While the crude protein, crude oil, crude ash and moisture content of lobster from Tatlı Lake were 16.10±0.23%, 0.59±0.39%, 1.60±0.24% and 81.60±0.26%, respectively, these were 15.49±0.13%, 0.61±0.06%, 1.57±0.36% and 82.24±0.19% for lobster in Gıcı Lake. At the end of the study, it was determined that the environmental and morphometric parameters, egg fecundity, biochemical composition and meat productivity of freshwater lobsters in Tatlı and Gıcı Lakes were similar between the lakes (p>0.05).