Lake Davis, California, September 25, 2007—In the war against invasive fish, desperate Californians are turning to chemical weapons.

The state's Department of Fish and Game has tried fishing, traps, and even electric shocks and explosions in the ten-year battle against voracious northern pike—a single one of which can lay more than 50,000 eggs.

So officials are now dumping 16,000 gallons (61,000 liters) of rotenone—a poison deadly to fish and also mildly toxic for humans—into Lake Davis, as seen in this photo.

A poisoning attempt in 1997 was unsuccessful, but officials hope that a new formulation will clean out the lake before the pike reach the Sacramento River, which connects to San Francisco Bay.

"We felt we really want to make sure we got those guys," department spokesperson Steve Martarano told the Associated Press.

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