Investigations on age, growth and mortality parameters of Ailia coila (Hamilton 1822) (Siluriformes: Ailiidae) from Brahmaputra River system of Assam, India

The present study deals with the detailed investigation on population dynamics of near-threatened catfish Ailia coila (Hamilton, 1822), which inhabits Brahmaputra River India and forms an important component freshwater inland fishery, providing nutritional financial security to local community. A total 1034 individuals were collected by weekly sampling from Uzanbazar Dhubri landing centres this river system September 2013 April 2014. estimated asymptotic length (L∞), growth coefficient (K) age at zero (t0) A. 268 mm, 0.87 yr-1 t0 = 0.000028 years respectively. Estimated mortality (Z), natural (M) fishing (F) 5.76, 1.63 4.13 Using von Bertalanffy formula (VBGF) attained end first, second third life 156, 221 248 equation fish can be written as Lt {1-e-0.87(t+0.000027866)}. exploitation ratio (U) rate (E) M/K 0.71, 0.72 1.87, Keywords: coila, Asymptotic length, Fishing mortality, Growth co-efficient,