Sex Dependent Catch Efficiency of Fyke Nets for Narrow-clawed Crayfish (Pontastacus leptodactylus): A Case from Eğirdir Lake (Türkiye)

Abstract

The present study aimed to investigate the effects of sex-related morphological differences in crayfish bodies on their escape rates from the fyke net used in fishing. The study, conducted in Eğirdir Lake (Isparta, Türkiye) with a total of 20 fishing operations, utilized commercial crayfish fyke nets equipped with 34 mm diamond mesh size. Statistical differences were determined between the body parts of female and male crayfish within the same length classes among the 1,529 crayfish examined, ranging from 31.80 to 149.00 mm in total length. These observed differences were reflected in the catch comparison results; however, the difference was found to be statistically insignificant. According to the study results, the crayfish fyke nets commonly used in crayfish fisheries in Türkiye, rigged with 34 mm diamond mesh, did not exhibit selectivity based on sex groups. In this context, it is considered that there is no need for any sex-specific regulation in crayfish fisheries in Türkiye.

Keywords

• Catch comparison
• Eğirdir Lake
• inland fisheries
• sustainability
• small scale fisheries

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