The otter is a carnivorous mammal that can live in both fresh-water and sea-shore habitats. The otter has a slim and long body with short legs and it has sharp claws on its feet, the underfur is dense and very soft in brownish colour above and cream below.

It is well adapted to an aquatic life and is very graceful when it swims in the water. It is a playful animal and enjoys making water slides and then sliding on them into the water.

It is a good hunter and its main diet consists of fish, crayfish, crabs, shellfish but during the winter the otter can use other sources of food such as birds, frogs and sometimes small mammals.

The otter is widely distributed in Mayo, good sites are Carrowmore Lake and Lough Carra where it can find an ideal habitat and the waters are clear and without pollution.

Its scientific name is Luntra luntra, while the Irish name is Madra Uisce meaning " water dog " and this gives a good idea of its general appearance.