Environnemental factors and growth of Cyprinus carpio (L ., 1758) in Ghrib dam (Ain Defla) Algeria

Abstract

Abstract The influence of environmental factors on growth and age of Cyprinus carpio (Linnaeus, 1758) was investigated monthly from August 2013 intil April 2016 in Ghrib dam lake. A total of 750 individus introduced of C.carpio were studied with passive fishing technique. The physical and chemical properties of the water of Ghrib dam were recorded, which is of average to good quality (eutrophic). The age of C. carpio was estimeted by the scalimetric method, it fluctuated between 0 and 14 years in both sexes. Total length of fish ranged from 11.44 cm to 61.5 cm and body weight of fish ranged from 24.29 g to 2696 g. The length-weight relationship of C. carpio represented negative allometry for both sex. The sex ratio was in favour of males (50.8%). The condition factor of males (0.85–1.31) and females (0.97–1.39) indicated that environmental conditions varied between poor and good. Fishing mortality is very high compared to natural mortality, stock of C. carpio is overexploited in the Ghrib dam (E = 0.65). The results of Factoriel Correspondence Analysis (FCA) revealed that the most significant environmental factor effecting growth of fish is Nitrite (NO2).