Fin Length and Total Length Relationships of Silky Shark Carcharhinus falciformis Landed at Tanjung Luar Fish Landing Port, West Nusa Tenggara, Indonesia

Abstract

Shark fins are a very valuable product for international trade. This study aims to obtain the equations describing the relationship between fin length and the total length of silky shark. Using the total length at sexual maturity (Lm), the equation is then used to estimate the fin length associated with this Lm, which can then be included in the recommendation for international shark fin trades. Data collection was carried out from March 2018 to February 2019 at Tanjung Luar Fish Landing Port, West Nusa Tenggara. All data were collected from 2,837 individuals of silky sharks, consisting of 1,416 females and 1,421 males. The total length of silky shark ranges from 61 to 282 cm for females and 18-283 cm for males. The relationships of first dorsal fin length and total length is DFL=2.0151+0.1243 TL (both sexes). Furthermore, the relationships of pectoral fin length and total length were found to be PFL=-8.0098+0.2127 TL (both sexes). The first dorsal fin length and pectoral fin length at the time the silky shark sexually matures were 23 cm and 35 cm, respectively. This fin-total length relationship can be used by the fisheries authority to determine the allowed minimum size of silky shark fins for export.