Growth, Mortality, and Yield per Recruit of Synodontis schall (Bloch and Schneider, 1801) in Roseries Reservoir, Sudan
Mujtaba El Khair Shuaib
Fish and Aquatics Research Centre, Animal Resources Research Corporation, Sudan.
Mutasim Yousif Mohamed Abdalla
*
Fish and Aquatics Research Centre, Animal Resources Research Corporation, Sudan.
Zeinab El Amin Alsharif Alttagi
Fish and Aquatics Research Centre, Animal Resources Research Corporation, Sudan.
Abdalla Mustafa Hamid
Fish and Aquatics Research Centre, Animal Resources Research Corporation, Sudan.
*Author to whom correspondence should be addressed.
Abstract
This study assessed the population bio-parameters of shield-head catfish Synodontis schall (Bloch & Schneider, 1801) in the Roseries Reservoir (Sudan), using length-frequency data analyzed with FiSAT software. The von Bertalanffy growth parameters were determined as an asymptotic length (L∞) of 50.4 cm, and a growth curvature (K) of 0.17 yr.⁻¹. Mortality rates were calculated with total mortality (Z) at 0.63 yr.⁻¹, natural mortality (M) at 0.46 yr.⁻¹, and fishing mortality (F) at 0.17 yr.⁻¹, resulting in an exploitation rate (E) of 0.28 yr.⁻¹. The species exhibited continuous recruitment, with a maximum exploitation rate (Emax) of 0.409. Results indicate low fishing pressure on S. schall in the reservoir, which is a relatively low level of productivity. The relationship between total length and body weight also revealed a negative allometric growth pattern (b = 2.193) with a moderate correlation (r = 0.764).
Keywords: Population dynamics, synodontis, fisheries, FiSAT, exploitation rate