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Least concern conservation status
Binomial nameMyocastor coypus
Coypu range map
Range of species in blue

The coypu, or nutria is very similar in appearance to a beaver.  They have light to dark-brown fur, and are also aquatic.  Unlike the beaver, their rounded tails have fewer hairs which are not as flat or as wide.  They are about one-third the size of an adult beaver. 

Coypu are sometimes misidentified as a muskrat, although they are over five times the size.  The tail of a muskrat, like a beaver lays flat, although more triangular.  

Coypu have long white whiskers, unlike beavers and muskrats which have black whiskers.

Coypu can weigh up to 20 lbs, with a body length up to 2 ft.  Their tails are long at 1-1.5 ft long, and have webbed hind feet.

They can be destructive, causing damage through burrowing.  The damage can erode river banks, cause flood-control levees to breech and weaken structural foundations.  

They also cause damage the plants in their environment as well.  They eat up to 25% of their body weight per day, but also destroy and waste approximately ten times as much again.  The damage they cause can threaten rare populations of other animals which rely on these habitats, as well as livelihoods of agricultural farms.