nutria, large rodent
A giant 20-pound rodent with the ability to destroy roads, levees and wetlands has been discovered in Stanislaus County.
A giant invasive rodent with the ability to destroy roads, levees and wetlands has been discovered in Stanislaus County.

Weighing in at 20 pounds and measuring 2 feet, 6 inches long, plus a 12-inch tail, the nutria live in or near water. They're also incredibly destructive.

"They burrow in dikes, and levees, and road beds, so they weaken infrastructure, (which is) problematic for flood control systems," California Fish and Wildlife spokesperson Peter Tira said.

The California Department of Fish and Wildlife is sounding an alarm about the invasive nutria.

When nutria aren't burrowing, they're eating. They can consume 25 percent of their body weight each day in vegetation, but they waste and destroy 10 times that.


Since 2017, more than 20 nutria have been spotted in Stanislaus, Merced and Fresno counties. However, that number could explode if they aren't dealt with quickly. Nutria can give birth to up to 200 offspring each year.

"We have traps out. We're setting traps. We have trail cameras," Tira said. "We're really asking for the public's help to report sightings so we can get a handle on the extent of the problem."

Nutria are native to South America, and they were introduced to California in 1899 for their mink-like fur.

Wildlife officials believed they were eradicated from the state in 1978 but now think a colony may have stayed under the radar and only recently reemerged.

Nutria is often mistaken for a beaver or muskrat, but it's identified by its white whiskers, rounded tail and webbed feet with just one toe free.