Among the things that make a Maine outdoors editor’s heart beat faster: When another editor sends a link to a clear photo of a mountain lion … and the caption says, “On a game cam in Harmony, Maine.”

That was the case on Thursday, and as the newsroom bustled around me, I started checking out the story.

First, the way-backstory: Many Mainers are certain that mountain lions live here. They’ll tell you they’ve seen ’em. Or their uncle did. Or their dad. Or their neighbor.

Mountain lion sightings are common … if, in fact, the sightings involve an actual mountain lion. For years, state biologists figured that if the big cats did live here, they were likely captive animals that had been released or escaped into the wild.

Many of the sightings were debunked more easily: Tracks in the sand often showed small footprints of a house cat, or dog-like prints.

But sometimes, after a sighting, there was no evidence that proved anything. After a mountain lion was hit by a vehicle and killed in Connecticut a few years back, biologists began to rethink their earlier assessment. That cat was matched to a DNA sample obtained in South Dakota. The cat had walked 1,500 miles east, likely looking for a mate.

Now, back to the mountain lion that was purported to have been captured on film in Harmony.

Much of the credit for unraveling the mystery goes to BDN computer wizard Will Davis, who coincidentally grew up in Harmony.

He provided a couple of sources from that rural town, and then started looking at other places — there were more than 2,000 — where the photo had been shared.

That led back to the Facebook page of Wildgame Innovations, which manufactured the trail camera that was used.

And it led us to Murray Muise of Yarmouth, Nova Scotia, the man whose camera captured the image back on June 2.

On Friday, I caught up with Muise via phone.

He wasn’t in Nova Scotia. He was in Calgary, Alberta … and so was the mountain lion.

Muise explained that he owns his own landscaping company, and from May until November he works in Calgary. He’s also an avid hunter, and like many other hunters, he uses game cameras to learn what critters are tromping around in areas he might hunt.

“[The camera] is just south of Calgary, in the Turner Valley,” Muise explained. “I didn’t expect to see [the mountain lion]. I expected moose and whitetail.”

That places the camera nearly 3,000 miles away from Harmony, Maine.

Muise said a friend knew a mountain lion was nearby, and had heard its vocalizations at night. But he never expected to see evidence of it, and is a bit leery when he checks that camera after looking at the photo.

“I check it every week. I look up every tree now,” Muise said. “They say when you see those, it’s too late. They’re on top of you.”

Wally Jakubas, a Maine Department of Inland Fisheries and Wildlife biologist who has researched plenty of reported sightings of cougars in Maine over the years, said that before he learned the origin of the photo, he saw evidence that it might not have been taken in Maine.

“The one thing that bothered me about the picture was the dense stand of aspen in the background,” Jakubas said. “While these occur in Maine, they are much more common in the Upper Midwest and West.”

And while it’s hard to know exactly who first tagged the photo as originating in Maine, Muise was amused that his trail camera photo had received so much interest.

“I thought it was pretty crazy. It’s just a picture,” he said. “And I thought it was funny that somebody else posted it and said it had been taken in Maine.”

Many Mainers, however, don’t care where this photo was taken. They’re still convinced that cougars walk among us.

“Someone saw one down in Canaan the other night,” one man told me during my effort to get to the bottom of the Harmony cougar story.

Who knows? He may be right.