Life history traits of leopard coralgrouper Plectropomus leopardus in the Okinawa Islands, southwestern Japan

The life history of the leopard coralgrouper Plectropomus leopardus was examined for the purpose of stock evaluation and to help maintain populations in the Okinawa Islands, southwestern Japan. Age was estimated from cut and burnt otoliths, and gonads were observed histologically to reveal the growth, spawning period and relationships between age and both sexual development and sexual maturation for P. leopardus in waters north of Okinawa Island. The three parameters in the von Bertalanffy growth equation, L _∞ , k, and t ₀, were estimated at 61.2 cm fork length, 0.289, and 0.41, respectively. The oldest individual obtained among the specimens was 18.8 years. The spawning period started in May and lasted until July. During this period, 50 % of females reached maturity at 43.3 cm fork length and at 5 years of age. Due to the sexual transition from female to male, the sex ratio decreased to 50 % at 59.8 cm fork length and at 10.3 years of age.