Susan Hart of Monroe sits on her tractor with the ruffed grouse she and her husband called Harriet. The grouse followed them for close to four months, then disappeared. They don’t know why. Photo courtesy of Forest Hart

MONROE — For months in the fall, Susan and Forest Hart had what could be described as a love affair with a female ruffed grouse that followed them around their farm outside Belfast. It landed on their heads, their shoulders and their deck to sit beside them.

They named the bird Harriet for Forest’s mother, because the grouse walked quickly and with intention, as his mother did. The Harts never fed the grouse, but, to their delight, it kept coming back around – jumping up on a tree branch near them or the ATV beside them, if not right on them. The bird even acquiesced to an hours-long photo shoot with Forest Hart, a wildlife artist.

Then after four months, without warning, the bird was gone. Now, the Harts are left wondering why it was drawn to them and what became of their feathered friend. And they’re not the only Mainers who in recent years have witnessed what’s known as a tame grouse, a phenomenon makes for unforgettable wildlife stories but puzzles scientists.

“It’s a great mystery,” said Jeff Wells, the science and policy director for the Boreal Songbird Initiative in Gardiner.

A grouse on the forest floor in Freeport peers at Rafael Adams of Cape Elizabeth. Adams learned of the grouse that approached people on a Facebook birding page and drove out to Freeport to see it. Photo courtesy of Rafael Adams

Three other Mainers who have had similar encounters include a professional wildlife photographer, an outdoor educator and a recreational guide. They live in different parts of the state – the foothills of the White Mountains, southern Maine and Aroostook County. But each told similar tales of a grouse landing on their shoulders or heads, following close on their heels as they hiked, purring back at them when spoken to and sitting on the hood of their tractor or trucks.

“It is the most intense wild animal interaction I have ever had,” said Rafael Adams, 46, the recreational guide from Cape Elizabeth. “And I am pretty into wildlife. But I have never seen something act unwild.”

The only distinct difference in the tame-grouse tales is that, in some instances, the birds appeared to want to befriend the people, while in other cases, the ruffed grouse acted more territorial, more threatening – however ornery a small puff of feathers just 17-inches tall can be.

“She had a serious attitude,” said photographer Paul Cyr of Presque Isle about one of two tame grouse he’s encountered in the past few years.

“I have a little farm (where) I like to play out back with equipment. She’d circle me two or three times and stand right in the way of my tractor. She would come at me and peck my jeans. There were times I got out there and went to get out of my truck and I’d open the door a crack and see her on the ground waiting. And, in my head, I’d hear that music from ‘Jaws.’ That’s the way it felt.”

‘A great mystery’

There are videos of tame grouse on the internet, but experts say it’s not commonplace. In his 11 years working as the state’s migratory and upland game bird biologist, Kelsey Sullivan has heard only five such stories of ruffed grouse – all second-hand.

Sullivan said biologists don’t know why ruffed grouse behave this way, but these occurrences have been documented for over a century. He said some theorize that ruffed grouse seek people for companionship or that hormones in juvenile male birds cause them to act confused and become overly affectionate toward people.

“I would feel privileged if a bird did that around my house. It’s kind of a special thing. It’s unique,” he said.

Forest Hart enjoys a visit by the grouse he and his wife named Harriet, which followed them around their 400-acre farm in Monroe, just west of Belfast. Photo courtesy of Forest Hart

Wells at the Boreal Songbird Initiative said he has only heard of a half dozen such accounts – and he’s studied grouse since he did his master’s thesis on the bird in the early 1990s.

He surmised it could be caused by the bird’s response to the reverberations in engines or motor sounds, such as with a truck, a water pump or lawn equipment. He thinks perhaps the humming of the engines mimics the drumming the birds make during mating season. But Wells said nobody has ever studied and tested this theory.

“It always was described as happening with an old tractor or some machinery. That’s why I think it’s related to sound,” Wells said. “But it requires careful analysis.”

Maine Audubon staff naturalist Doug Hitchcox said it would make sense to attribute the odd behavior of a bold grouse to the bird acting territorial, but the “tame and approachable behavior is tough to know for sure.”

The Cornell Lab of Ornithology, one of the world’s foremost authorities on bird behavior, does not have anyone studying the species and had no explanation.

Wells said what’s even more strange is that the behavior is not a characteristic of any other bird species, even other types of grouse.

“It’s perplexing,” Wells said. “It’s very difficult to study because it only happens with some birds. It would be hard to find the one or two that happen each year in Maine (to study). Even if it was twice that, it still would be a tough thing to study.”

Not-so-wild encounters

Ruffed grouse are among the smallest, size-wise, of the 10 species of grouse in North America, but they are the most widely dispersed game bird on the continent, according to Inland Fisheries and Wildlife.

The bird weighs about 17 to 25 ounces and has feathers in shades of brown and tan that blend perfectly with the boreal forest where the birds thrive on green leaves and insects.

State biologists do not have a population estimate for ruffed grouse. But Inland Fisheries and Wildlife reports that more than 27,700 square miles of Maine’s 35,300 square miles is made up of forest land that is ideal grouse habitat. In these swaths of woodland, individual birds have a home range of about 30 acres.

Paul Cyr with a grouse on his camera, in 2015. Photo courtesy of Paul Cyr

In Presque Isle, right down the road from the North Maine Woods, the epicenter of ruffed grouse habitat in Maine, Cyr lives on a 160-acre farm. In his 67 years living in northern Maine, the professional wildlife photographer has experienced a tame grouse twice – one a friendly encounter and, the most recent, a tiny terror.

The first one came around in 2013 for two months, and he could get down on one knee and pat it. “It followed me around like a dog,” he said.

The other, he encountered for two winters, in 2015 and 2016. This ruffed grouse chased him off an area that was about 10 square acres. When he drove along his dirt roads into that stretch of his land, the bird would hop on the hood, flap her wings and try to come in the window. Cyr believes the bird was a female because male grouse, in general, have tail feathers longer than their backs. Cyr said this bird had tail feathers about as long as its back. The grouse let him spend up to two hours taking photos at close range, but Cyr had to defend himself when it flew up into his face.

“I think she thought she owned the property out back. Inevitably, she’d come at me with less than honorable intentions,” Cyr said.

Adams, a lifelong outdoorsman and recreational guide, said the 30 minutes he spent with a grouse last spring in Freeport was the most extraordinary experience in nature he’s ever had.

Adams, a birder who had never seen a grouse before, read on the Maine Birding Facebook page about a specific grouse coming up to people in Freeport, so he went to try to find it near Wolfe’s Neck Farm. Soon after he played a grouse call, it appeared on the side of the road. He didn’t feed the bird and said it wasn’t friendly. At times, it pecked his leg and chased him around his car. He said it almost demanded to be “paid attention to.”

But the bird had no problem with him getting down on his stomach to take photos just a foot away.

“The weird thing is, grouse are typically shy,” Adams said. “You usually don’t see them, you usually see them flying away and hear the thump, thump, thump of their wings. But this one, it was like it wanted to sit in my lap.”

Leigh Macmillen Hayes of Bridgton saw a tame grouse four different times last year while hiking on land owned by the Greater Lovell Land Trust. Twice, she was with other people, but the crowd didn’t deter the bird. Like others, she called the experience in nature unparalleled.

Considering Hayes is the education director at the Greater Lovell Land Trust and a Master Maine Naturalist who spends nearly every day outdoors, that’s saying something.

She always saw the grouse on the same trail, and she said they always “parted ways” in the same place. She told a friend, who went to go look for the bird, and when the woman stepped out of her parked car, there it was.

“She texted me with a video and said, ‘Look what I found.’ It’s crazy,” Hayes said. “It almost got to be an addiction – looking for the bird. I’d frequently find myself hiking somewhere else and wanting to stop by there. I needed to see it again. The whole story was amazing. How many times do you get to walk with a grouse? It may never happen again.”

Friends of fowl

Then there are the Harts.

Susan Hart of Monroe looks around at the ruffed grouse she and her husband called Harriet. The grouse followed them for close to four months, then disappeared. They don’t know why. Photo courtesy of Forest Hart

The two Maine natives have lived in the Canadian outback and vacation there often. They do not feed wildlife. They believe in keeping wildlife wild. That’s why they found the tame grouse they called Harriet such a strange encounter.

“Everything was her idea. Everything was initiated by her,” Forest Hart said.

Hart, a wildlife artist who has his life-sized bronze sculptures of moose, deer and mountain lions displayed on their land, first saw the bird in early October about 20 feet from the door of his art studio, next to his pickup truck. As is his practice, he went to photograph it and was stunned at how close it let him get.

“I’m a sculptor, so I need lots of photographs of animals,” Hart said. “She seemed to have no fear of me and was just walking around feeding.”

The next day, he saw the bird again. However, rather than flying away, the grouse moved toward Hart, as close as 8 inches away. It walked around him in a complete circle, as if executing some strange ritual.

Over the next few months, the bird would approach both Susan and Forest Hart when they were outdoors, sometimes running toward them. It would fly up and land on their head or shoulders, or on Forest’s plow when he was moving snow. Forest Hart spent 32 photo sessions with her, one lasting as long as two hours. The bird would make a humming sound, “like a mewing,” Susan Hart said.

“Once she followed us on a walk in the woods for over an hour,” Susan Hart said. “She’d even walk next to us.”

They never let the bird inside their house, but they got attached to their ruffed grouse friend.

“I miss her,” Forest Hart said. “We don’t know where she went. Maybe she found other grouse to bond with. I hope so.”

A grouse lands on Paul Cyr’s car. Photo courtesy of Paul Cyr