The beaver rat, also called nutria or more rarely swamp beaver, tail beaver, tail rat, water rat, is a rodent species originating from South America and naturalised in Central Europe. The beaver rat reaches a body length of up to 65 cm and weighs between eight and ten kilograms as an adult. Its round, scale-covered, barely hairy tail is also about 30 to 45 centimetres long. The animals thus reach almost the same body size as a beaver