California's 20-pound invasive nutria problem could be worse than previously imagined
SFGate -

In the spring, the Department of Fish and Wildlife began to warn the public about the dangers of nutria, the destructive rat-like mammal currently burrowing into central California's wetlands. But in the past few months, only 200 nutria have been exterminated, 100 of which were found in a pond on a single private farm in central California.

And as the agency prepares for an intensive survey of the Sacramento-San Joaquin River Delta, officials say they have no idea what the actual numbers will...

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