Fishery and the population dynamics of the blood clam Anadara granosa (Linnaeus) in the Kakinada bay

Abstract

The blood clam, Anadara granosa is fished throughout the year in the Kakinada Bay by fishermen residing in 15 villages. (During 1978 - 81. at Yatlmoga Kakinada) the blood clam catch, effort and catch per unit effort varied from 104 to 222 t, 3414 to 6295 man - days and 30.4 to 35.3 kg / man day respectively. The instantaneous rates of total (Z), natural (M) and fishing (F) mortality rates are estimated at 3.9,1.3 and 2 6 respectively - In the presently exploited population, other parameters estimated are the age at recruitment (tr) = 0.29 yr, age at first capture [to] = 1 - 0 yr and the maximum age [ta] = 5.62 yr. At present the yield in weight per recruit [Yw /R] is about 9 - 5 g; It Increases with increase In F and it is less for greater values of tc. It is suggested that at the current level of F, maximum Yw / R value of 10 42 g is possible if tc is reduced to 0.6 yr.