Investigation on feeding biology of southern crested newt, Triturus karelinii strauch, 1870 (Urodela: Salamandridae)

In this study, the feeding biology of Triturus karelinii (Strauch, 1870; Urodela: Salamandridae) population in the Tamzara district (Şebinkarahisar, Giresun, Turkey) was investigated. Stomach contents of 119 salamanders captured in May, June, July in 2012 and April in 2013 were removed by flushing method. Totally, 13583 individual prey items were identified from the stomachs of 116 salamanders. The remaining 3 ones had no prey items in their stomachs. It is detected as the average of the prey from the stomach 117.09, average of volume 14.95. From the results of the stomach contents, it was found that this salamander fed on Cladocera, İnsecta and Gastropoda respectively. Insecta were found predominantly in frequency (%96.55), Gastropoda were found predominantly volumetric (%65.12) in diet. Prey was found from 74 of 75 captured female salamanders and 42 of 44 male salamanders. It was determined from the significant correlation between length of salamander and size of prey that increases the length of the salamander also increased the size of prey consumed. Moreover, the male and female members of the total stomach volume has been found to be a significant difference and it was revealed that female salamanders were larger than male salamanders and they fed on more preys than males. According to stomach contents of the females and males show that both females and males had similar prey various. Among months, number of prey, the total volume of the stomach and average volumetric of prey were found the significant correlation. Average number of prey found in June, the average volume of prey in the months of April and May, which is the maximum has been detected. The electivity index showed that this species avoided from Trichoptera larvae (Ei=-0.97), Notonectide nimph (Ei=-0.96), Ceratopogonidae larvae (Ei=-0.95), Coleoptera adults (Ei=-0.91), Araneae (Ei=-0.91), Naucoridae nimph (Ei=-0.89), Odonata nimph (Ei=-0.45) and Gastropoda (Ei=-0.42) and preferred Ephemeroptera nimph (Ei=0.96), Chironomidae larvae (Ei=0.84), Daphnia (Ei=0.69), Hirudinea (Ei=0.31), Dytiscidae larvae (Ei=0.22). These preferences is done according to size and morphological features of prey were determined.