Snowy owl takes flight from a mountain in Acadia National Park on Mount Desert Island. Snowy owls are sometimes found in Acadia during the winter. They return to the Arctic to breed in the spring. Credit: Courtesy of Liz Eudy

When snow and ice cover the granite peaks of Acadia National Park, the crowds disappear. But a new visitor arrives.

Flying down from the Arctic, snowy owls descend upon Maine each winter in limited numbers, and a handful of these birds find a temporary home atop the tallest mountains of Acadia on Mount Desert Island.

For months, these large, ghostly birds remain on mountains such as Cadillac and Sargent, hunting for rodents in the alpine zone. They also do plenty of resting, enjoying the seclusion of these remote settings — for the most part.

In recent years, word has gotten out. Excited winter hikers, birders and wildlife photographers have shared their knowledge of snowy owls in Acadia by word of mouth and through social media platforms. It’s no longer a secret where these majestic birds can be found, for those willing to take an arduous off-season trek.

Credit: Courtesy of Kjetil Rossignol

“Usually by December, they’re here, and by the middle of March, maybe late March, they’re gone,” said Jeff DiBella, a wildlife photographer from Sullivan who has photographed the snowy owls in Acadia several times. “[Photographing them is] not for everybody. Your hands get pretty cold … But I like the challenge, and frankly, with the spikes on, I like defeating the ice.”

In response to more and more people learning about the snowy owls, Acadia National Park erected signs on select mountains this winter, alerting hikers to when they’re entering an area frequented by snowy owls.

“Our biggest concern is that we do not want to attract crowds in any way toward these birds,” said Christie Anastasia, the park’s public affairs specialist. “If folks know about them, great. If folks come across them as a pleasant surprise, great.”

The signs Acadia has recently installed are meant to be educational, Anastasia said. They state that snowy owls are sensitive to human disturbance and should be observed from a distance.

Credit: Courtesy of Acadia National Park

Finding a balance

Snowy owls are a fairly rare sight in Maine. They’re only seen during the winter, and only at select locations. Furthermore, they’re famously beautiful, with snow white feathers and bright yellow eyes. So naturally, these birds are sought after by birding enthusiasts and wildlife photographers.

The issue is: how can people view snowy owls — and other wildlife — without negatively impacting them?

“The thing to remember about snowy owls is, when they fly down here, they may be encountering people for the first time,” said owl expert Scott Wiedensaul, co-founder of project SNOWstorm, a project established in 2013 to track snowy owls in North America. “These birds are coming from the most remote places in North America.”

Perhaps as a result, snowy owls — especially young snowy owls — are known to be more approachable than most other wild animals, Wiedensaul said.

“So the inclination is to get close,” he said. “It’s just human nature. But if the bird is watching you, you’re too close. If the bird is paying attention to you, that’s an indication that you need to stop and back off. If you push it until the bird flushes (is forced to fly), then you’ve done the wrong thing.”

Credit: Courtesy of Erin Willey

Often people will assume that when snowy owls fly, they’re hunting, Wiedensaul said. But snowy owls hunt primarily at night. When the sun is up, these birds are usually trying to sleep.

“They catnap and doze all day,” Wiedensaul said. “Then right around dusk, they become active. But when they’re in places like public beaches where people can reach them, they get bumped constantly because people are trying to get close.”

At places like Biddeford Pool, a well-known and easily accessible snowy owl spot in Maine, this has been a real cause of concern as crowds of people have gathered to watch and photograph these birds.

Even atop Acadia mountains, there have been reports of people disturbing these owls, causing them to fly and waste energy during the day. There have also been reports of dogs off leash in Acadia’s snowy owl habitat, Anastasia said, even though it’s a park rule that dogs must be kept on leash at all times. To address this problem, the park is considering the creation of a docent program that places volunteers on the summits of mountains to observe human-owl interactions and educate visitors.

Not only do snowy owls waste energy when disturbed by humans, they’re also put at risk of being spotted by daytime predators, such as bald eagles, Wiedensaul said. And if the owl is hunting, it could lose its opportunity to capture a meal if spooked by a person — or dog.

Credit: Courtesy of Erin Willey

Snowy owls in Maine

Acadia National Park isn’t the only snowy owl haunt in Maine. Other spots frequented by these birds include Biddeford Pool, Clarry Hill in Union, Beech Hill in Rockport and Weskeag Marsh in South Thomaston, according to Michael Gray, a birder from Rockport. All of these areas have one thing in common: open space.

“They like a nice, unobstructed view,” Wiedensaul said. “These owls are coming from the Arctic tundra where they don’t know about trees. So they come down here and there are all these big, alien green pointy things. So they tend to gravitate toward open landscapes that look more like home.”

For this reason, snowy owls are repeatedly found at Maine airports, where they are often captured and relocated by biologists to reduce the risk of airplane-bird collisions. They’ve also been found at sprawling business parks, blueberry barrens and large fields. But the number of these birds on the Maine landscape changes from winter to winter.

The number of snowy owls migrating down to Maine and other states and Canadian provinces during the winter is closely tied to natural cycles in the Arctic’s lemming population. The lemming, a small rodent, is the primary food source for snowy owls during breeding season.

“Snowy owls have probably the most complex migration and movement patterns of almost any bird,” Wiedensaul said. “They can be sedentary and remain in the Arctic [year round]. Some migrate predictably to one place winter after winter. And some are highly nomadic. They’re just kind of all over the map and highly individualistic.”

Regardless, some of Acadia’s mountains are consistently seeing snowy owls from year to year. The open, remote terrain above the tree line on these mountains fits the description of what snowy owls are generally attracted to, Wiedensaul said. It’s likely that the owls are feeding on rodents such as mice and voles. Furthermore, the close proximity of the ocean may offer the birds additional sources of food, such as sea ducks, grebes and gulls.

“We know that snowy owls along coastlines feed very heavily on water birds,” he said. “I don’t know if that’s what’s happening here, but I wouldn’t be surprised.”

Credit: Courtesy of Jeff DiBella

A ‘magical’ bird

Erin Willey of Ellsworth has seen snowy owls on Acadia mountains for the past three years. Like many birders, she initially heard about the owls through word of mouth. In anticipation of spotting them, she upgraded her camera so she could photograph the birds from a distance.

During her many winter hikes in Acadia, she’s successfully spotted them, and she’s also failed to find them. It’s hit or miss, she said.

“I don’t sit there and wait,” Willey said. “If they’re up there when I’m there, cool. But I don’t stalk them, and I don’t wait for them … This year, from December until just a few weeks ago, I made five trips up and didn’t see them.”

Just a few weeks ago, Willey took one final hike to look for the snowy owls this winter, and she found success. With dark, distinct bands on its white feathers, the owl appeared to be female, Willey said, though it’s difficult to tell the difference between male and female snowy owls. Females are more apt to have dark markings than males, but so are younger owls. Size can also be an indicator, since adult females are generally larger than males, but that’s challenging to detect unless two owls are sitting side by side.

“She was on the ground on the rocks,” Willey said. “But the rocks had this icy kind of cover and so she was camouflaged like nobody’s business. The wind was whipping. Her feathers were everywhere, and she was just as happy as could be, stretching her talons out. She just kind of sat there … It’s really just kind of a magical thing because they’re so beautiful — and they’re so temporary.”

Aislinn Sarnacki is a Maine outdoors writer and the author of three Maine hiking guidebooks including “Family Friendly Hikes in Maine.” Find her on Twitter and Facebook @1minhikegirl. You can also...