Life history and spawning potential of blue swimming crab Portunus pelagicus (Linnaeus, 1758) in Pamekasan, Madura Island, Indonesia

Abstract

Blue swimming crab is one of Indonesia’s most valuable marine crustaceans, experiencing high fishing pressures for export, which could lead to the depletion of stocks. Knowledge of blue swimming crab spawning potential is imperative for understanding the stock’s status. This study aimed to estimate the spawning potential of blue swimming crab (Portunus pelagicus) based on their life history parameters. Fourteen thousand five hundred thirty-three crab samples were collected from fishers caught using the collapsible traps from January to December 2021 in Pamekasan. The biological data, including carapace width, weight, sex, and maturity level, were measured. Length-based spawning potential ratio method was used to estimate the spawning potential ratio. Results showed the growth parameters, CW∞= 179.55 mm, K = 0.98 year−1, and tmax=3 years. Size at first maturity was estimated at 102 mm carapace width, while the size at first capture was 112-121 mm. Egg-berried female crabs were observed throughout the year, with two distinguishable peaks occurring in Jan-Feb and Aug-Sep. The overall estimates of the SPR met the reference point limit. This study gave insights that the stock status of BSC in Pamekasan was not at risk of recruitment impairment, but management actions should be initiated for stock rebuilding.