Age and Growth of Epinephelus fasciatus from northern Red Sea

Document Type : Original Article

Authors

1 Marine biology department, Faculty of Science, Al-Azhar University

2 Marine Science Department Faculty of Science Suez Canal University

Abstract

Age and Growth of the fish Epinephelus fasciatus (n=443) from Northern Red Sea were investigated, during the period from June 2006 to May 2007. The t-test analysis for the length-weight relationships showed a significant difference between b values, where male are positive allometric while female and sexes combined are isometric. The "Kc" and (Kn) factor was studied monthly and according to size classes, where females usually outnumbered males. The total average of Kc for sexes combined was 1.428 (SE.± 0.4134), this value is indication of a good condition. The value for both Kc and Kn increased in line with increased fish size until the size 31.4, and then decreased in value. On the other hand, both condition factors showed fluctuations among months, where the lowest value was recorded during August (within spawning season). The back calculation method was used to determine the age and growth for E. fasciatus. According to Bhattacharya method eight age group were verified growth parameters L∞=36.75 cm (TL), K= 0.35 year -1 and t0= -0.41121 were derived from Ford and Walford method. The highest range of growth recorded in the first year as it grows about 14.32 cm. Then the rate of growth either slowed down slightly or get closer to being steady.

Keywords