Growth, mortality and spawning season of the spangled emperor (Lethrinus nebulosus Forsskal, 1775) in coastal waters of Hormozgan Province in the Persian Gulf and Oman Sea

Abstract

The population parameters and spawning season of the Spangeld emperor (Lethrinus nebulosus) were studied in coastal waters of Hormouzgan province. The monthly calculated mean values of gonadosomatic index (GSI) of females were indicate to increase from February, reach the highest in March and decline in June. The spawning season peak of L. nebulosus occurred in March. The Von Bertalanffy growth parameters, L∞, K and t0 were estimated as, 67.2cm, 0.16.year-1 and -1.161 year, respectively. The relationship between weight and length (Fork Length) can be expressed as W=0.051 L2.722, which indicates that Spangled Emperor has negative alometric growth. Using length converted catch curve, total mortality (Z) was estimated as 1.13 year-1 and natural mortality was estimated using Pauly's equation, as 0.57 per year. Finally, the fishing mortality (F) was 0.56, which gives an exploitation rate (E) of 0.50.