Stock assessment and management of the rabbitfish Siganus rivulatus from the Southern Red Sea, Egypt

Abstract

Rabbitfishes, family Siganidae, are one of the most abundant fishes inhabiting the Red Sea and now widely distributed in the Mediterranean. Age and growth of Siganus rivulatus, the most common species, were studied from samples collected randomly between October 2017 and October 2018 from Shalatein landing site. Otoliths of 2000 specimens were used for age determination and the maximum attained age for this species was four years. The von Bertalanffy growth parameters L∞, K and to and the instantaneous annual rates of total, natural and fishing mortality were estimated and consequently the exploitation rate was determined. It is found that the current exploitation level is higher than the optimum one reflecting the intensive exploitation of S. rivulatus in the Southern Red Sea, Egypt. Yield per recruit analysis revealed that fishing effort should be decreased. This can be adopted through closed seasons/areas, increase of mesh size, increase of minimum landing size and setting of a total allowable catch (TAC).