Length based growth and stock assessment of the longnose trevally Carangoides chrysophrys (Cuvier, 1833) from the Arabian Sea coast of Oman

Abstract

A study on the growth and stock assessment of the longnose trevally, Carangoides chrysophrys (Cuvier) was conducted using length-frequency data collected during April 2005 – March 2007 from the Arabian Sea coast of Oman. The size of C. chrysophrys in commercial catches ranged from 21 to 72 cm TL and about 52% of the fish belonged to the 0-1 year age group. The length-weight relationship was W = 0.0369L2.7123 (R2 = 0.967). The von Bertalanffy growth (VBG) parameters estimated for the species were: L∞ = 75.6 cm, K = 0.47 y-1 and t0 = -0.37 y, and the life span appeared to be 8-9 years. The annual total mortality (Z), natural mortality (M) and fishing mortality (F) coefficients stood at 1.2, 0.74 and 0.46, respectively. The exploitation rate (E) was 0.38. While the average standing stock was estimated at 2,633 t, the total stock was 4,455 t. The estimates of MSY varied from 1,363 to 1,580 t. At the current F, the Yw/R, TB/R and SSB/R were 236 g, 653 g and 364 g respectively. The study indicates scope for development of artisanal fishery for C. chrysophrys in the Arabian Sea off Oman.