Pertumbuhan dan Laju Eksploitasi Rajungan (Portunus pelagicus) di Perairan Pantai Labu, Sumatera Utara

Abstract

Crab (Portunus pelagicus) is a fishery resource in the coastal waters of Labu, North Sumatra which is the main commodity and contributes greatly to the welfare of fishermen. The high demand for crab causes overfishing. The purpose of this study was to determine the growth, exploitation rate and condition and economic value of crab in the waters of Labu Beach, North Sumatra. This research was conducted in March-June 2024 using random purposive sampling method with one month interval. The number of crab samples was 212 with 107 males and 105 females and carapace width ranging from 59-165 mm. The results of the relationship between length and weight of crab showed negative allometric. Based on the growth parameters, the crab has L∞ (210.8 mm), K (0.52 years), and t0 (-0.1833). The annual total mortality rate (Z) is 3.26, natural mortality (M) is 0.707, capture mortality (F) is 2.552 with an exploitation rate (E) of 0.782 in the overfishing category. Crab recruitment occurred in 3 peaks namely March (18.89%), May (14.76%) November (8.03%) with partial spawning. The results obtained 62 crabs with carapace <10 cm and 56 crabs in TKG III and TKG IV. The economic value of crab is grade A with a price of 90,000-115,000, grade B ranges from 45,000-75,000 and grade C ranges from 30,000-45,000.