Patterns of variation in dietary composition among four populations of Alpine salamanders (Salamandra atra prenjensis)

Abstract In this paper we studied the diet in four allopatric populations of alpine salamanders Dinarides ( Salamandra atra prenjensis ). Food consumption was assessed by stomach flushing while food availability pitfall traps and netting. We aimed to: (i) assess realized dietary niche, (ii) investigate prey preferences, explore individual specialization, clustering nestedness. All have an equally wide span that is among largest reported for terrestrial salamanders. On other hand, amount ingested rather low compared to salamander species; quantity consumed did not differ but younger individuals fed more than adults. composition somewhat differed sex/age classes. all populations, bulk consisted beetles, spiders, snails millipedes; except such also preffered together with centipedes isopods. For most categories, direction electivity indices same across populations. none a nested pattern interindividual subdivision resources registered. However, indications specialization modularity were observed disclosing broad niche composed smaller niches cluster along axis. Overall, very similar structural characteristics there little evidence local differentiation probably due absence drivers change.