Well, that’s an odd sight. That’s what diver Jim McKeeman remembers thinking last Saturday when he came across a crustacean that was a long – very long – way from home.

McKeeman was diving with a few friends in the Santa Monica Bay, doing a regular weekend outing in search of lobsters. While the California Spiny Lobster were plentiful, he couldn’t believe it when he saw a Maine lobster crawling around underwater. “I saw this guy on my last dive, he was all by himself, next to a rock,” McKeeman recalled. “As I got close to him, I thought, ‘This is weird. What’s he doing here?’”

The Maine lobster – known to be feistier than his California cousins – wasn’t going to get plucked from the ocean without a fight. “He raised his claw and came at me,” said McKeeman, of Tustin. “They are pretty aggressive.” He thought about leaving the 4-pound lobster in the sea, but then said no one would believe him without documentation. So he got his camera out and got a few photos with the crustacean.

McKeeman speculated that someone likely bought it from a restaurant and figured they could save it and let it go into the ocean.

That could be the case, said Jeff Landesman, chief aquarist for the Cabrillo Marine Aquarium in San Pedro.

“People get shipped lobsters from the East Coast, it could be a gift or they ordered it to cook, and they have second thoughts of throwing them in a pot and they don’t know what do do with it,” he said.

Landesman warns that this shouldn’t be done.

If lobsters not native to the area stay here and reproduce, they may decimate other shellfish that call Southern California home.

There’s not a big concern that east coast lobsters are invading local waters, since they don’t reproduce well here, either because there’s not many of them or they have trouble surviving in the water temperatures off Southern California.

When asked which ones taste better, Landesman said it’s up to an individual’s preference.

“It depends on who you talk to,” he said. “People like the Maine lobsters because of all the meat in the claws, but others say the tail of the California lobsters have more meat.”

McKeeman hopes to find the answer to that question.

“We’re going to do a taste-test comparison when we get together to have a lobster dinner,” he said, noting he will probably steam the lobster and then finish it on the grill, served with plenty of butter, of course.

McKeeman figured he was doing his part to rid Southern California of an invasive species.

“He really didn’t belong here anyway,” he said. “If they were to take hold here and breed, that could be a problem.”