Employees in old Town Hall not only smell a rat, they've got photographic evidence.

A night-vision camera set by animal control officers last week snapped a photo of a salt marsh rat inside the Credit Union offices on the building's second floor.

Edward Crowley, the credit union director, said the surveillance operation was activated after municipal employees came in to work one morning and discovered that something appeared to have been burrowing in the dirt of a potted plant.

"There was dirt all over the place," he said. "Our first thought was it was a mouse."

Sticky traps baited with peanut butter were set out, but the next day the peanut butter was gone although the traps had not been sprung. That's when the camera was put to use and captured the image of the culprit.

Public Works Director Richard White said a

professional exterminator has been brought in and plastic, child-

resistant traps have been placed around the office building's foundation.

White said he doesn't know if there is more than one rat in the building.

"There's usually more than one," he said.

Bait left for the rat will force it to go outside seeking water once ingested, White said.

"They're native to the area," he said, and are active at night.

The rats live in salt marshes, White said, and don't nest in buildings.

Tax Collector Stanley Gorzelany said when his office staff heard the news about the rodent they made sure to clear food off counter- and desk-tops and that the food is stored in a metal cabinet.

"There are traps set up everywhere, but we have not seen any trace of it," Gorzelany said, of the rat.

Crowley said a Credit Union employee working late one night did get a glimpse of the interloper, whose alleged size seems to have grown as word about its presence has spread.

The rat looks rather imposing in the photo, Crowley said, because it is right in front of the camera. In reality, he described it as being about 6 or 7 inches long.

Some workers have inaccurately called the creature a "swamp rat," which is actually a nutria, native to Argentina and brought to the U.S. in the 1930s for its fur. There have been efforts in Maryland and Louisiana to eradicate the swamp rat, which is destroying marshland. The nutria can grow to have a body 25 inches long, with a 16-inch tail and weight of about 22 pounds.

The rodent at old Town Hall, White said, is not a swamp rat, but a salt marsh rat.

Health Director Sands Cleary said so long as the rat is expelled from the offices quickly, "the chances of any health risk are minimal." He also stressed that employees should make sure they do not leave any food out that could attract the creature.

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