Morphometric Characteristics of Freshwater Crayfish (Pontastacus leptodactylus Eschscholtz, 1823) Caught in Sapanca Lake, Türkiye

This is the first study providing information on some morphometric parameters for Pontastacus leptodactylus from Sapanca Lake (Sakarya), Türkiye. This study was conducted from June - 2016 to October - 2017 and a total of 264 crayfish were caught, being 146 females and 118 males. The results revealed that the average total length for the population was 91.89±15.68 mm (TL±SD) (94.75±15.91 mm for females, 88.36±14.72 mm for males), and the average total weight for the total population was 27.27±16.84 g (TW±SD) (29.02±17.54 g for females, 25.09±15.74g for males). The sex ratio was computed as 1.24:1 (female to male). A strong positive statistical relationship was determined between the total length and total weight of females, males, and both sexes (r2: 0.90 – 0.95). This statistically strong relationship was also valid between other body parts, such as carapace length, width, and weight. The regression analyses for total length-total weight relationships also revealed that the whole population exhibited positive allometric growth (b=3.186) regardless of sex, and the condition factor for all sex groups was computed to be over 3 (K=3.23±0.60 SE).