Growth and Feeding Ecology of Dnieper chub Petroleuciscus borysthenicus (Kessler, 1859) in Şahinkaya Reservoir, an Artificial Water Body of an Island Ecosystem (Gökçeada, Turkey)

Bio-ecological studies and life-history traits of small-bodied fishes are critical for the un- derstanding of their ecological role as well as the assessment of their position and continuity in the eco- systems. The current study goals to present initial data on growth and feeding habits of small-bodied Petroleuciscus borysthenicus inhabited in an island ecosystem (Gökçeada, Turkey). During the season- ally sampling surveys from May 2020 to January 2021, a total of 163 specimens were collected from Şahinkaya Reservoir using electrofishing. SL and W values of samples ranged from 2.6–10.0 cm and 0.32–25.68 g, respectively. LWR and K values were estimated for all specimens as W=0.017×SL3.114 (r=0.988) and 2.04 (±0.28), respectively. F:M sex ratio was calculated as 1:1.33 with no significant difference from the ratio of 1:1 (X2=0.02; p>0.05). Diet of the species comprised of ten different food items. Plant (63.6%) was the most preferred food item from the point of frequency of occurrence (F%), pursued by Diptera (31.8%) and Odonata (12.7%). According to IRI (%) values of food items, Diptera was the dominant food item in all seasons. B and BA values were estimated as 3.18 and 0.24, respec- tively. The results showed that P. borysthenicus was more selective on conveniently accessible food materials in the environment and its food preference was affected by seasonal food supply.