The age composition, growth parameters and reproductive properties of Gobio hettitorum, Ladiges, 1960 caught in Yeşildere Stream, Karaman (Central Anatolia), were studied by sampling carried out between July 2006 and June 2007. A total of 498 specimens were examined. The age composition of the species ranged from 0 to 5. The specimens of the population were 44.97% (224) male, 47.99% (239) female and 7.03% (35) unidentified. The mean fork length and weight of the samples ranged from 30.0 mm to 161.0 mm and 0.29 g to 40.42 g respectively. The average condition factors varied from 1.03 to 1.38. In females, the average maximum condition factor was 1.59 in June 2007 and in males, it was 1.42 in October 2006. The reproductive period of G. hettitorum was recorded from March to July, and average maximum gonadosomatic index values were estimated to be 12.94 for females and 2.33 for males in May 2007. According to the gonadosomatic index values, the maximum egg diameter of females was 0.74 mm in May 2007. Fecundity was calculated as 420 (age class 2) to 4.418 (age class 5) eggs/female.
There are few studies on the growth and reproductive strategy of the genus Gobio in Europe. The current study investigated the growth and reproductive characteristics of G. hettitorum inhabiting Yesildere Stream, providing important information for the conservation of this endemic species.