Sahar F. MEHANNA
Basic population parameters of the hooded cuttlefish Sepia prashadi, in the Arabian Sea were described from samples collected during the demersal trawl survey of the Arabian Sea between September 2007 and August 2008. A total of 6869 S. prashadi with mantle lengths (ML) ranged from 3.4 to 21.2 cm were analyzed. Age and growth were studied using progression analysis model by applying Bhattacharya method. There were no significant differences in population parameters between sexes. The asymptotic ML was 24.13 cm, while the growth co-efficient K was 0.81/year and t0= -0.14 year. Mean total, natural and fishing mortalities were 3.66, 1.54 and 2.12 per year respectively. The exploitation ratio (E =0.58) suggests that the fishing pressure on S. prashadi in the Omani coastal waters is slightly high. Relative yield per recruit and relative biomass per recruit analysis showed that S. prashadi stock in the Arabian Sea is in its optimum situation as the current E is lower than that which gives the maximum Y’/R. For the management purpose and to reduce the risk due to the sampling bias, the current exploitation rate should be reduced by about 38% to achieve E0.5 as a target reference point and the present length at first capture should be raised to about 14 cm ML to conserve the first spawners of the stock.
