Otters are semi-aquatic mammals and well adapted to life in the water. They have a long, streamlined body which can grow up to 1.2m in males (known as dogs) and 1m in females (called bitches).
With their webbed feet and powerful tail they can swim at up to 12km per hour underwater, though they do have to come to the surface for air
Otters mainly live in freshwater rivers, lakes and streams, where the banks are lush or there are suitable islands, reedbeds or woodlands for foraging, breeding and resting.
They can also inhabit coastal areas, though they do need to come inland to breed and sleep. Their habitats need to support adequate food supplies - namely fish, but also birds, small mammals, amphibians, crustaceans and molluscs.
Welsh sites which have been designated as Special Areas of Conservation (SACs), because they are home to relatively high densities of otters, include the Rivers Teifi, Tywi, Eastern and Western Cleddau, Usk and Wye, and Cors Caron, a large wetland area which feeds into the River Teifi.
If you are lucky enough to spot an otter in the wild, keep a respectful distance from it and its habitat.
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