A study on the some biological aspects Longnose Trevally (Carangoides chrysophrys) in Hormozgan waters

Abstract

Aspects of the biological features such as age and growth , the reproductive cycle , food and feeding of the Longnose Trevally (Carangoides chrysophrys) were studied from a total 376 specimens collected by use of trawl fishing in Hormuzgan waters between February 2014 and February 2015. The minimum and maximum total length during different months were between 25.5 and 80 cm respectively. Weight-length relationship for Longnose Trevally was W = 0/0064L 2/9004. This fish had an isometric growth. Fishes aged using sections of their otoliths . The equation of growth for Longnose Trevally obtained Lt = 85(1-e -0/266(t+1/443) ). Total mortality rate for Longnose Trevally was 0.412. LM50 and TM50 for Longnose Trevally was 46 cm, 2 years. Sex ratio(femail : male) for Longnose Trevally was 1/42:1. Maximum absolute and relative fecundity for Longnose Trevally were 479992 and 354 respectively. The highest GSI in April (2.86) and the lowest was in June 2014 (0.43). It has a long spawning season from January to May and spawning peak was observed in May. Longnose Trevally was Relatively low feed (CV= 65.49). Main food for Longnose Trevally were bony fish(Fp= 91.67). Random diet of Longnose Trevally were crustaceans (Fp = 4.17) (shrimp, crab and squilla) and mollusks (Fp =4.17) (cutlle fish, Squid), respectively.