Trophic diversity of the otter (Lutra lutra L.) in temperate and Mediterranean freshwater habitats

摘要: Aim To analyse the geographical patterns in composition and diversity of otter’s (Lutra lutra L.) diet their relationship with climatic characteristics. Location European freshwater habitats under Mediterranean temperate regimes. Methods Thirty-seven otter studies were reviewed, twenty-one from sixteen areas. All based on spraint analysis results expressed as relative frequency occurrence seven main prey categories. Principal Component Analysis was performed to extract gradients composition. Pearson’s correlation t-tests used assess between characteristics (composition, taxonomic richness) variables. Results A clear latitudinal gradient observed. Otter more diverse featured classes southern localities, while species piscivorous towards north, where it predated upon a higher number fish families. This pattern similar when localities Europe compared. otters behaved generalist predators than ones, relying less fish, aquatic invertebrates reptiles. Main conclusions Geographical differences feeding ecology seem be related two contrasted conditions affecting populations. The can act highly specialized predator ecosystems, which do not suffer dry season have comparatively stable water regime compared ones. However, unpredictable availability areas, affected by strong spatial temporal shortages, favours diversification diet.