Meat Yield and the Length–Weight Relationships of the Narrow‐Clawed Crayfish, Pontastacus leptodactylus (Eschscholtz, 1823)

The present study investigated the length-weight relationships and meat yield of narrow-clawed crayfish, Pontastacus leptodactylus (Eschscholtz, 1823), in Kocahıdır Irrigation Reservoir. Between July 2015 and June 2016, a total of 653 individuals (255 females and 398 males) were sampled, and their carapace lengths (CL), total lengths (TL), and total weights (TW) were measured. The female-to-male ratio for the entire population was found to be 0.64:1.00. The results showed that the CL of the narrow-clawed crayfish ranged between 37 and 90 mm (39-79 mm for females and 37-90 mm for males), while the TW ranged from 10.10 to 165.61 g (11.13-90.01 g for females and 10.16-165.61 g for males). The TL of female individuals was 114.09 mm, with a weight of 40.43 g, while the TL of male individuals was 116.32 mm, with a weight of 53.45 g. The ratio of individuals above the minimum legal-size limit of 100 mm was determined to be 80.70% for the crayfish population in Kocahıdır Irrigation Reservoir. Regression analysis indicated that the TL-TW and CL-TW relationships for female narrow-clawed crayfish exhibited negative allometric growth, while males showed positive allometric growth in terms of the TL-TW relationship and isometric growth in terms of the CL-TW relationship. Isometric growth was observed in the whole population for both male and female individuals in terms of TL-TW and CL-TW characteristics. Female individuals with carapace lengths ranging from 43-82 mm had a chelae meat yield of 2.48%, an abdomen meat yield of 11.38%, and a total meat yield of 13.85%. Male narrow-clawed crayfish with carapace lengths ranging from 35 to 90 mm had a chelae shear meat yield of 4.13%, an abdomen meat yield of 10.52%, and a total meat yield of 14.64%.