SACRAMENTO (CBS / AP) — More than 400 nutria have been captured in the first year of an effort to eradicate the invasive South American rodent from California.

The state Department of Fish and Wildlife said Monday the semi-aquatic rodents were trapped in five counties in the San Joaquin Valley.

Nutria are an agricultural pest, destroy wetlands critical to native wildlife and threaten water delivery and flood control infrastructure through destructive burrowing.

Coypu, Nutria or River rat (Myocastor coypus), Myocastoridae. (Photo by DeAgostini/Getty Images)

Nutria were imported in the early 1900s for the fur trade, but the market collapsed and the rodents escaped or were released. Small populations were eradicated in the 1970s, but nutria were again discovered in 2017.

Fish and Wildlife notes that San Joaquin Valley farmers have donated five tons of sweet potatoes to use as bait to trap nutria.

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