Leslie Population Estimation for Turkish Crayfish (Astacus leptodactylus Esch., 1823) in the Keban Dam Lake, Turkey

The population size was researched by using Leslie method on the zones of Keban Dam Lake where crayfish is fished for commercial purposes. The data were compiled by using effort expended and catch obtained by 28 fishing boats during 2012 crayfish fishing season. 28 fishing boats fished 16,867 kilograms of crayfish during the fishing season by using 45,600 pieces of crayfish fyke nets. It is determined that the quantity catch per unit effort (CPUE) varies between 2.74 to 6.35 kg/100 fyke nets/week during the 9 weeks fishing period. The population size at the beginning was estimated to be 28,450 kg (at minimum legal length of >= 10 cm). The 95% confidence interval of this estimation was calculated to be 25,607-32,533 kg. Similar researches on crayfish populations concluded that removal method can offer very important details.