AUBURN – Like unwanted guests, the squatters were taking over the city’s parking garage. They showed up at dusk and roosted on the top floor. They harassed city employees headed home after a long day, made an ungodly racket and left a worse mess.

It was so bad in the Mechanics Row parking garage that the city began sending regular police patrols around at dusk to disperse the delinquents.

What else can you do with crows?

“We’d like to know,” City Manager Glenn Aho said. “We’ve heard of using lights and sounds to chase them away, or something else. But if anyone has any ideas, please, let us know.”

A rowdy flock of crows began making the city’s sole parking garage a wintertime habitat this month. After trying a number of solutions, the city began sending a police patrol car, sirens blaring and lights flashing, through the garage each night at dusk, just as the birds begin to settle.

So far, it’s worked. The crows have stayed away for most nights this week.

“But we don’t know if that’s because of something we’ve done or because of the change in the weather,” Community Services Director Eric Labelle said. “We’ll have to see.”

There’s little that can be done about the birds permanently, said Tom Hayward of the Stanton Bird Club.

“There is no easy solution or someone somewhere would have patented it,” Hayward said. “Sounds and lights have all been tried, but there really isn’t much you can do to rid south-central Maine of crows. You might manage to move them from one area, but they’ll just go someplace else. And they might be back.”

City employees began noticing the birds in the garage early in December.

“I saw what they left behind, and at first I thought it was probably (Canada) geese flying overhead,” Assistant City Manager Laurie Smith said.

The Twin Cities are home to 1,000 of the birds and they have their favorite places to roost: the hills around Edward Little High School, the Lewiston High School tennis courts and neighborhoods all around the area.

All they want is shelter, but something open enough to make a quick escape if they must. Parking garages with no ceilings are perfect.

“In the summer, they like stands of pine trees,” Hayward said. “They like open areas that are good for communication. There’s safety in numbers, and at least one or two are always keeping watch while the rest sleep.”

Typically, flocks of crows roost overnight in the same spot for weeks at a time before trying new places. During the day, they disperse and forage all over the city, Hayward said. “At sunset you see them streaming across the sky headed for their favorite roosting spots.”

Hayward guessed that the Twin Cities’ crows have a few favorite wintertime roosts and that the Auburn garage has become the latest.

“Maybe it’s just warmer in town now and that’s why they’re here,” he said

Labelle said one problem is that the birds are unflappable. They’re truly unimpressed by people.

“When you leave at the end of the day, they don’t scatter,” he said. “They just move out of the way, just enough. But they won’t fly away unless they think you’re pursuing them. Other than that, they don’t care.”

Labelle said he’s trying to find a permanent solution. Fireworks are an option, and so are lasers and strobes.

“There’s one idea to use the recording of a sound of a crow in distress,” he said. “That makes them think they’re in danger.”

They’ve also talked of using plastic predators to frighten the birds.

But they’re pretty smart, he said. “They get used to things pretty easily.”