The relative influence of riparian habitat structure and fish availability on otter Lutra lutra L. sprainting activity in a small Mediterranean catchment

摘要: The influence of riparian habitat structure and fish availability on otter Lutra lutra marking activity was studied at the head Guadalete river (southern Spain). Otter in study area could be ordered along two gradients structural properties (altitude, stream order, channel form, water current, bank vegetation), quality bankside plant species composition. Generally, higher altitude sites had more dense vegetation cover better quality. dominant upstream assemblage consisted such as Rubus sp., Salix spp., Arundo donax, which provided secure shelter for otters. In contrast, downstream typical Tamarix africana, Nerium oleander helophytes, overall lower but wider eutrophic. sprainting correlated with this gradient, being sites, especially areas dominated by short scarce human presence. Similarly, biomass greater downstream. A strong positive correlation observed between larger size. Thus, variability intensity upper seemed to dependent availability, secondly disturbance, than particular features, including composition growing banks. Implications conservation management otters Mediterranean are discussed.