Age, Growth, Mortality and Yield per Recruit of the Filefish Stephanolepis diaspros (Fraser-Brunner, 1940) (Pisces: Monacanthidae), in the Gulf of Suez, Egypt

摘要

The filefishes Monacanthids have a relatively high occurrence in the trawl landings of the Gulf of Suez, representing about 7% of the total trawl catch. The leasarjaket filefish Stephanolepis diaspros is the most abundant filefish in the area. In the present work the population structure of S. diaspros was studied. Samples were collected from the commercial trawl catches during the period from November 2004 till March 2007. The anterior dorsal spine was used for age determination. Validation of the ageing method was carried out by analyzing the monthly length frequency distributions. The life span was found to be four years. The values of natural mortality (M), total mortality (Z) and fishing mortality rates were 0.702, 1.88 and 1.18 year super(-1), respectively. Results of the exploitation rate (E = 0.628) and relative yield per recruit showed that the filefish resource in the Gulf of Suez is overexploited and that juvenile individuals are the target of the fishery. Some implications for the fishery management were proposed.