Some aspect of population dynamics of three penaeid shrimp (P.monodon, P.semisulcatus and M.monoceros) from the Bay of Bengal, Bangladesh.

Abstract

In the Bay of Bengal of Bangladesh area the values of asymptotic length (La) for tiger shrimp (Penaeus monodon), green tiger shrimp (Penaeus semisulcatus) and brown shrimp (Metapenaeus monoceros) were found to be 30.0 cm, 23.5 cm and 16.5 cm for male and 32.1 cm, 27.0 cm, and 19.4 cm for female respectively while the growth co-efIicient(K) were 0.94, 0.80 and 1.5 year¯1 for male and 0.97,0.90 and 1.52 year¯1 tor female respectively. The length growth performance index ( ')of the Pauly and Munro's function were in the range of 2.61- 3.00 Natural mortality, fishing mortality and total mortality for tiger, green and brown shrimps were in the range of 1.72-2.75,2.13-3.94 and 3.85-6.59 respectively. Length frequency data analysis through FiSAT programme reveals that the studied three species were under fishing pressure. Spawning rnonths appeared to be from April to July for main cohort. The recruitment pattern of the penaeid stocks suggested one main pulse of annual recruitment and current exploitation rate were in the range of 0.553-0.667.