Identification of stingrays species and exploitation rate of blue-spotted maskray (Neotrygon kuhlii) landed at TPI tanjung beringin, Serdang Bedagai Regency, North Sumatera Province

Abstract

Serdang Bedagai Regency has fisheries and marine potential demersal species of stingray in TPI Tanjung Beringin. The current study used a survey and descriptive method, accompanied by sample collection and morphology identification, as well as determining the rate explotation of fish landed in TPI Tanjung Beringin. A total of five species were successfully identified: Neotrygon kuhlii, Brevitrygon heterura, Aetoplatea zonura, Maculabatis macrura and Rhynchobatus australiae. The most dominant stingray species landed in TPI Tanjung Beringin namely of Neotrygon kuhlii, so that condition was an analysis of Neotrygon kuhlii weight length relationship of fish and body weight is negative allometric growth is more dominant than weight gain. The growth rate Von Bertalanffy is L ∞ (infinity) value is 300.30 mm, K value is 0.42 and t0 value is -0.68, the fish growth can be influenced by internal and external factors. Mortality and exploitation rate of Neotrygon kuhlii total mortality (Z) value is 1.01, natural mortality (M) value is 0.59408, fishing mortality (F) value is 0.4192 and exploitation rate is 0.7105 as long as indicators high fishing mortality and decreasing natural mortality indicate a state of growth overfishing.