Length-Weight Relationship of the Blackmouth Catshark (Galeus melastomus Rafinesque, 1810) on the Turkish Coasts of the Mediterranean Sea

This study investigates the relationship between the total length and body weight of the blackmouth catshark Galeus melastomus Rafinesque, 1810 sampled along the Mediterranean coast of Türkiye within the boundaries of the Geographical Sub-Area 24 during August and September 2023. A total of 336 individuals, 106 females and 230 males, were caught using bottom trawl. The total length and body weight of females range from 17.6 to 54.2 cm and 15.5 to 630 g, respectively. For males, the range is from 16.1 to 50.7 cm in length and from 13.0 to 426 g in weight. When considering both sexes together, the range is from 16.1 to 54.2 cm in length and from 13.0 to 630 g in weight. The average weight of males was calculated to be 169.43 ± 7.21 g with a standard error, while the average length of males was 36.96 ± 0.64 cm. Similarly, the average weight of females was 145.34 ± 15.67 g, and the average length of females was 32.32 ± 1.06 cm. The average length of all individuals without sex separation is 35.5 ± 0.56 cm, and the average weight is 161.83 ± 6.99 g. The length-weight relationship is determined as W = 0.002×L3.13 (r2 = 0.97) for females, W = 0.003×L2.94 (r2 = 0.98) for males, and W = 0.003×L3.00 (r2 = 0.98) for all individuals. The results obtained from this study are expected to contribute to filling the knowledge gap by highlighting the relationship between the length and weight of the blackmouth catshark in the examined area. It will also enable comparisons with other deep-sea locations in the Mediterranean Sea on this particular species.