While Rhode Island and other sections of the Northeast are experiencing an “invasion” of Snowy Owls from the Arctic Circle, don’t expect the birds to hang around all that much longer.

That’s the opinion of Dr. Kevin J. McGowan, course instructor at the Cornell Lab of Ornithology.

McGowan’s advice is to see the birds before they head north again, which he expects to happen by February given experiences in prior years. The Audubon Society of Rhode Island estimates there are six birds in the state given the sightings reports they have received and what can be found on eBird, a website run by the Cornell Lab of Ornithology.

A Snowy has been spotted on numerous occasions at Conimicut Point. It has been seen perched on the lighthouse and standing on the sandbar. Mature birds stand three feet high and have a five-foot wingspan.

“They’re like creatures from another planet,” said McGowan. “We may not see them again for a long time.”

McGowan said there have been other invasions of Snowy Owls, adding, “we don’t know why we have a big burst of owls this year.”

One theory is that the population of the owls is linked to the cycles of lemmings, a primary food for the raptor. During periods where there are high numbers of lemmings or voles on the Arctic tundra, the birds are capable of producing large clutches resulting in an abundance of the owls. And with more predators and less prey, the birds leave the arctic in search of food.

“It’s all about food,” says McGowan dispelling the thought that the birds could be seeking warmer climes. The bird’s natural habitat is north of Hudson Bay and Baffin Island. The area is devoid of trees and McGowan said the birds don’t build nests, but find depressions in which to lay their eggs.

Surprisingly, since it was thought the owls leaving the Arctic would be under stress and malnourished, McGowan said those trapped at Boston’s Logan Airport were found to be fit. The owls prefer open spaces such as fields and beaches, as well as airports, where it is feared they could be a hazard.

Patti Goldstein, spokeswoman for the Rhode Island Airport Corporation, said Snowy Owls have been spotted at Green and Quonset airports.

“It’s a tough business to be a raptor,” said McGowan. He said hunting down prey that is looking to escape the claws and beak of an owl could make it difficult to get a meal. He estimated about half of the birds don’t live to be adults.

The Snowy is equipped with big feet that McGowan said gives it the ability to catch small mammals, like lemmings or waterfowl such as ducks.

While taking in the comparatively warm weather of Rhode Island and elsewhere in the Northeast, McGowan suggests the birds are dining on waterfowl, although he doesn’t have confirmed reports. He didn’t think they would be after gray squirrels, as they would be in or around trees and the birds are not accustomed to hunting in the woods.

McGowan, who has been birding since 1971, said spotting a Snowy is rare.

“Get the heck out there and see them,” he advised. “We don’t know when this is going to happen again.”

As the birds are unaccustomed to humans, McGowan described them as “fairly approachable.”

And apart from being a rare visitor to the region, McGowan added, “they’re on the top of the bird chain.”