A Midsummer Night’s Diet: Snapshot on Trophic Strategy of the Alpine Salamander, <i>Salamandra atra</i>

oleh: Luca Roner, Andrea Costa, Paolo Pedrini, Giorgio Matteucci, Stefano Leonardi, Antonio Romano

Format: Article
Diterbitkan: MDPI AG 2020-05-01

Deskripsi

Information on the trophic ecology of the Alpine salamander, <i>Salamandra atra,</i> is scattered and anecdotal. We studied for the first time the trophic niche and prey availability of a population from an area located in Italian Dolomites during the first half of August. Considering that <i>S. atra</i> is a typical nocturnal species, we collected food availability separately for diurnal and nocturnal hours. Our aims were: (i) to obtain information on the realized trophic niche; (ii) to provide a direct comparison between trophic strategy considering only nocturnal preys or considering all preys; (iii) to study trophic strategy of this species at the individual level. In two samplings nights we obtained prey from 50 individuals using stomach flushing technique. Trophic strategy was determined using the graphical Costello method and selectivity using the relativized electivity index. During the short timeframe of our sample, this salamander showed a generalized trophic strategy. The total trophic availability differed significantly from nocturnal availability. Interindividual diet variation is discussed in the light of the optimal diet theory. Finally, we highlighted that considering or not the activity time of the studied taxon and its preys may lead to a conflicting interpretation of the trophic strategies.