SOME BIOLOGICAL ASPECTS OF Chalcalburnus sellal(Heckel) IN TUZ CHI RIVER – NORTH IRAQ

Abstract

This work was conducted in Tuz Chi River which is one of Al-Audaim river tributary, Salah – Alddin Province during the period between June 2004 to June 2005. The study includes some biological aspects of Chalcalburnus sellal (Heckel), (sex ratio, food, growth and reproduction). Sex ratio (male: female) was 1:1. Insect was found the main food item 39.52 % of the food content with 62.90% frequency, followed by plants particles and their seeds 34.43% with 72.58 % frequency and organic matter 18.43 % . Fish was found omnivores, tends to animal food more than plant food, animal food occupied 41.74% and plant food 39.02% . Significant differences in the food intake between months and different length groups were observed. The maximum gonada somatic index( GSI ) was 5.45 for male and 11.64 for female in April. The length of smallest mature male was 103mm and female was 106 mm. The growth was allometric, the growth in weight increased with a rate of more than the cubic length. The condition factor ( K ) ranged between 0.54 - 1.06 with averaged 0.74, and relative condition factor ( Kn ) ranged between 0.76-1.15 with averaged 1.00. A significant difference in condition factor between different months was observed.