Age and growth of iridescent toothcarp Aphanius mento (Heckel, 1843) (Cyprinodontidae) in Seyhan Reservoir (Southeastern Mediterranean, Turkey)

The population structure of Aphanius mento in the Seyhan Reservoir was studied on the basis of 834 fish specimens (516 males and 318 females) caught on a monthly basisbetween September 2013 and August 2014. Fish were collected using dip nets of tulle with a 1mm mesh size. The maximum age of fish was found to be 4 years for both sexes combined, the 1 year old age group comprised 62.20% of male samples. The overall sex ratio of females to males was 1:1.62. Von Bertalanffy growth parameters were L_∞=54.33 mm, K=0.399 year^-1,  t₀ =-1.168 years for females, L_∞ =52.72 mm, K=0.397 year^-1, t₀=-1.137 years for males, and L_∞=56.50 mm, K=0.386 year^-1,                t₀=-1.257 years for both sexes.The length (TL) - weight (W) relationship was W= 0.00051xTL^2.635, (r= 0.965) for males, W=0.00088xTL^2.464, (r= 0.987) for females and W=0.00066xTL^2.554, (r = 0.974) for both sexes. Condition factor ranged from 1.696 for males and 1.613 for females to 1.664 for both sexes. The mean condition factor (CF) was not significantly different between the sexes among all fish during different months (p >0.05). The present study represents the first comprehensive information on the population structure of A. mento in the Seyhan Reservoir. The results of this study will contribute to the population management and conservation of this species and be useful in increasing knowledge on its ecology and biology.