Distribution and diet of recovering Eurasian otter (Lutra lutra) along the natural-to-urban habitat gradient (river Segura, SE Spain)

摘要: In the catchment of River Segura (SE Spain), ongoing Eurasian otter (Lutra lutra) recovery and concurrent spread human settlements are resulting in increasing records into urban areas. We analysed diet along a natural-to-urban gradient, with main aim assessing to which extent man-driven variation food availability affects its feeding habits how this secretive mustelid can thrive apparently unsuitable habitats. From 2016 2019, we collected 521 spraints, monitoring 37 sampling stations (mean length ± SD = 0.5 ± 0.3 km). natural areas, percent cover undisturbed banks was highest, lowest number water abstraction systems, whilst pollution highest Introduced red swamp crayfish (Procambarus clarkii) fish formed bulk diet. The two most preyed fish, Luciobarbus sclateri Pseudochondrostoma polylepis, were among abundant species river, confirming generalist behaviour otter. contribution non-native on average low, while invasive exceeded overall importance all habitats except Overall, data did not allow attesting as limiting resource for otters contrast, marking intensity varied consistently gradient (from 0.31 0.65 spraints/100 m urban- respectively), suggesting that disturbance (i.e. habitat modification pollution) may play major role shaping distribution.