Endemic Muar, Malaysia Oyster Crassostrea (Magallana) saidii Wong & Sigwart, 2021 Approaches Optimal Harvest Despite Year-Round Multiple Recruitments

Abstract

Population dynamics provides insight into how the population changes in structure over time. The insight is especially paramount for species with limited distribution and of conservation concern, such as Crassostrea (Magallana) saidii Wong & Sigwart, 2021 (Sigwart et al., 2021). The species is a recently described oyster endemic to the Muar estuary, Malaysia. The species’ size-weight relationship and population structure were assessed in 2019 to determine its population dynamic. Results indicated that the oyster showed a negative allometric growth with a coefficient of 2.5422 (b < 3). The observed asymptotic height (SH∞) was 15.23 cm, with a growth coefficient (K) of 0.69 per year. The low coefficient value was indicative of a slow growth rate, where it sets within the range of typically long-lived species. The oyster’s growth performance index (φ/) was estimated at 2.204. The level of exploitation (E) index of the oyster (0.42) was lower than annual fishing mortality (1.27), indicating the C. (M.) saidii population was utilized close to the optimum yield. The oyster’s recruitment pattern was continuous, peaking from April to June (18.46% to 13.82% oyster recruits) and September to November (10.68% to 12.37% recruits). The information of the current study is useful for sustainable management and proper utilization of the C. (M.) saidii oyster.