Study of some morphometric, reproductive and feeding traits, of Salmo trutta in Taleghan River

In 2018, in order to study a few biological characteristics, including length-weight relationship, condition factor, fecundity, age frequency, and morphological characteristics of Salmo trutta, a total of 38 specimens were collected in three upstream stations, Grap, Gathedeh, and Dehdar (tributaries of the Taleghan River). Some of the collected samples were transferred to the laboratory after fixation in the buffer 10% formalin and 29 morphometric and seven meristic traits were measured and counted, respectively. In addition, based on the conservation importance of the studied species, a number of morphometric traits of the few specimens were analyzed using the acquired high-quality pictures by ImageJ software. The results showed that the samples have 4 age groups, including 1, 2, 3, and 4 years old. The highest and lowest frequency was one-year-old group with 73.7% and 4 with 2.6%, respectively. The sex ratio was 1.8 (male): 1 (female). Based on the results, the length-weight relationship was obtained as Y = 0.0004x2.39. The condition factor was in the range of 0.71 to 1.26, as well as absolute fecundity of the Taleghan population was 168-379. In investigating the feeding habits, a wide range of macrobenthos was observed, indicating its dependence on available food items.