The European otter (lutra lutra) is an aquatic mustelid 60-65 cm long, plus a 35-55 cm tail, with a shoulder height of about 30 cm and a weight of 6-15 kg. Its body is slim, suitable for swimming nimbly, also thanks to the membranes between the toes. Its sight is sharp even underwater. The coat colour is dark brown on the back, lighter on the belly. It feeds on fish, shellfish, rodents and birds.
The natural habitat of the otter consists of pristine aquatic environments. In Abruzzo the otter is widespread in the purest rivers and mountain streams. The Nature Reserve of the Lake of Penne and the Otter Centre in Caramanico Terme collaborate in the conservation of this valuable, beautiful and endangered inhabitant of the Italian rivers.