Recognized in the United States as an invasive wildlife species, nutria have been found in at least 20 States and most recently in California. The nutria's relatively high reproductive rate, combined with a lack of population controls, helped the species to spread. In many regions they cause severe damage.

When did nutria become invasive?

Nutria, also known as coypu or swamp rats, are large rodents that live in areas with lots of freshwater. These mammals are native to South America and were introduced into the United States between 1899 and 1930 through the fur industry, according to the U.S. Fish and Wildlife Service (FWS).

How is nutria a threat?

Nutria cause extensive damage to wetlands, agricultural crops, and structural foundations such as dikes and roads. They may also threaten human health and safety and serve as a reservoir for tularemia and other diseases.