The role of prey abundance and flow regulation in the marking behaviour of Eurasian otters in a Mediterranean catchment

► We examined marking behaviour of Eurasian otter in a Mediterranean catchment. ► Otter selected shallow sites far from the bank to locate latrines. ► Otter selected sites where fishing was easier. ► Latrine sites showed a higher abundance of calandino in tributaries during summer. ► Otter selected crayfish when calandino, its main prey, was difficult to catch.