DefinePK

Abstract

ABSTRACT The current stock status of two Parrotfish, Hipposcarus harid and Scarus ferrugineus in Jeddah was assessed. Scales were used for age determination and back calculations of length-at-ages. The growth parameters were estimated to be: the asymptotic length L∞ = 54.044 cm, the growth coefficient K = 0.168 year-1, and age at zero length to = -0.707 year for H. harid and L∞ = 51.238 cm, K = 0.170 year-1, and to = -0.889 year for S. ferrugineus. The total ‘Z’, natural ‘M’, fishing ‘F’ mortality coefficients and current exploitation ‘Ecur’ were 0.96, 0.294, 0.670 year-1, and 0.69 year-1, respectively for H. harid and 0.77, 0.299, 0.471 year-1, and 0.61 year-1 respectively for S. ferrugineus. The maximum yield per recruit at the current fishing mortality was 108.1 g for H. harid and 137.6 g for S. ferrugineus. The biological reference points: Fmax = 0.401 year-1 and F0.1 = 0.245 year-1 for H. harid and Fmax = 0.434 year-1 and F0.1 = 0.307 year-1 for S. ferrugineus were lower than the current fishing mortality, reflecting an over-exploitation for both species. The current fishing mortality is recommended to be decreased to the target reference point F0.1 = 0.453 year-1 for H. harid and F0.1 = 0.466 year-1 for S. ferrugineus after increasing the age at first capture to be 3 years for both species.