Population Dynamic and Spawning Potential Ratio of Tiger Shrimp (Penaeus Monodon) Fisheries Using Double Rig Trawl in the Arafura Sea, Indonesia

The population dynamics and spawning potential ratio (SPR) of the tiger shrimp (Penaeus monodon) in the Arafura Sea, Indonesia, were studied to support sustainable fisheries management. This research measured carapace length distribution, length at first capture (Lc), growth parameters, mortality, and SPR using the length-based spawning potential ratio (LB-SPR) method. Data were collected from shrimp trawl vessels operating in the Arafura Sea over one year. Results showed that the carapace length of captured tiger shrimp ranged from 30.2 to 99.8mm, with an average of 62.03mm. The estimated Lc was 52.43mm, indicating that most captured shrimp had reached gonadal maturity. Growth parameters based on the von Bertalanffy growth model indicated an asymptotic length (L∞) of 102.82mm and a growth rate (K) of 1.10/year. Total mortality (Z) was estimated at 3.85, with natural mortality (M) at 1.37 and fishing mortality (F) at 0.33, resulting in an exploitation rate (E) of 19%. The SPR analysis yielded a value of 31%, which is below the sustainability threshold of 40% but has not yet reached a critical level. These findings indicate that the tiger shrimp stocks in the Arafura Sea are in a moderate condition but are at risk of overexploitation. Therefore, quota-based fisheries management and stricter fishing gear regulations should be reinforced to ensure the sustainability of tiger shrimp resources.