Age, growth and reproduction of the lizard fish Saurida undosquamis from the Gulf of Suez, Red Sea, Egypt

The lizard fish Saurida undosquamis represents one of the most commercial fish in the Gulf of Suez. The growth and reproductive biology of the species were studied. The age was determined from otolith readings of the collected specimens from the Attaka Harbor through the period from September 2011 to April 2012. The results show that the life span of the sampled fish was seven years. The estimated von Bertalanffy growth equation was L_t=51.252 (1-e^-0.131(t+1.45)), the calculated lengthweight relationship was W= 0.004 L^3.107. Seasonally distribution of gonado-somatic index (GSI) values showed that the main peak of GSI was in spring. The results of gonad development stages show that, Saurida undosquamis is a synchronous spawner. The size at which 50% of fishes are mature was 15.0 cm for males and 15.5 cm for females, which indicates that all individuals over one year of age were sexually mature. The results indicated that juvenile individuals are one of the targets of the fishery and the protection of the juveniles is probably the key factor for the sustainability of the resources.