BODEGA BAY, Calif. -- Bay Area scientists are working to get rid of an unwanted visitor from Australia, NBC11's Damian Trujillo reported.

Ted Grosholz of the Bodega Bay Marine Laboratory said he doesn't have anything personal against the green crab -- but make no mistake -- it's his mission is to wipe them out.

"We are doing everything we can to eradicate the European green crab," Grosholz said. "It's an introduced species. It's not a native species."

Grosholz said the crab somehow hitched a ride from Australia to the Bay Area in the ballast of a commercial ship around 1994.

"It's reduced the population of native shore crabs and native clams by about 90 percent. So, it's really had a large impact on the food web," Grosholz said.

Science once thought eradicating an introduced species was impossible.

"Ten years ago, if you asked any scientist or any manger if they could eradicate a species that came into a coastal environment, they'd just say, 'No.' (The) cat's out of the bag. (The) genie's out of the bottle."

For the last year and a half, the team has used traps and nets to catch green crabs around the harbor. They've already removed about 11,000.

"In the beginning our traps... we were getting 40, 50 crabs per trap," said Becca Kordas of the Bodega Bay Marine Laboratory. "As you saw today we were getting four to six max."

The work is usually done waist-high in mud. Grosholz said the effort is paying off.

"By removing them, even getting them down to a small, low level, maybe not eradication. We are actually seeing the harbor begin to recover," Grosholz said.

The researchers said they don't expect to ever completely remove the green crab from Bodega Bay, but their work will set an example for other communities battling non-native species.

"This is a model of how to do it," Grosholz said. "If we have a species that shows up that's very limited, then we really can come in with all guns blasting and get rid of it."