Nutria are a non-native species to North America, having been introduced to compete with the beaver fur market. They are semi-aquatic and will destroy a garden overnight, ruining small trees, bushes and the general landscape.
Because these animals are an invasive species, trapping and removal is encouraged by Washington Department of Fish and Wildlife. Fencing the bankside can help deter the animals from damaging property. Nutria are known burrowers, digging out the bank and shorelines for a den spot.