Meet one of the most unwanted critters in the wetlands… Nutria (Myocastor coypus), an invasive species, is a large aquatic rodent that strongly resembles beavers with its light to dark brown fur and orange teeth. This orange color comes from having a strong enamel that includes iron. Nutria can be distinguished from beavers by their white muzzle with long, white whiskers and rounded tails.
Native to South America, nutria were first introduced to the U.S. for the fur trade in the late 1890s. While they were present in California in the 1940s and 1950s, they were thought to have been eradicated in the 1970s. A population of nutria was found in the San Joaquin Valley in 2017.
Nutria are common in freshwater like rivers, lakes, and wetlands, but are also known to inhabit brackish coastal water areas. Damage caused by nutria comes in many forms: burrowing complex dens, intense herbivory, and carrying pathogens and parasites. These behaviors threaten levees, trigger erosion, destroy native plants, and threaten native and endangered species that rely on wetland habitats.
If you suspect or observe potential signs of nutria, report it immediately to the California Department of Fish & Wildlife at https://wildlife.ca.gov/Conservation/Invasives/Report