Population Dynamics of Venus Clam Meretrix meretrix from the Moheshkali Island in the Cox’s Bazar Coast of Bangladesh

Abstract

The population structure, growth, mortality and exploitation status of Venus clam Meretrix meretrix were examined in the Moheshkali channel of Bangladesh coast between June 2003 and May 2004. Monthly length frequency data of M. meretrix were analyzed by FiSAT software for estimation of population parameters like asymptotic length (L is proportional to), growth co-efficient (K) and recruitment pattern to evaluate the status of the stock. Asymptotic length (L is proportional to) was 8.14 cm and growth co-efficient (K) was 0.97 yr-1. The growth performance index (φ/) was 2.07. The growth pattern showed negative allometric growth with an asymptotic weight (W is proportional to) of 129.69 g obtained. This Venus clam attained 5.05 cm at the end of one year. Total mortality (Z) was estimated by length-converted catch curve at 2.63 yr-1, fishing mortality (F) at 0.02 yr-1, and natural mortality (M) at 2.61 yr-1. The exploitation level (E) of M. meretrix was 0.01 and the maximum allowable limit of exploitation (Emax) was 0.58. The recruitment pattern was continuous with one major peak event per year. Habitat temperature, dissolved oxygen and salinity range of Venus clam were 25.5-31°C, 4.02-6.50 mg.L-1 and 12.36 to 26 ppt, respectively. The exploitation rate (E=0.01) indicated that the fishing pressure on M. meretrix was very low and the stock condition might be unexploited in the Moheskhali channel of Bangladesh.