Look at the squirrel's fur and whiskers against the backdrop of the lake. As someone who has done a LOT of photo altering, those whiskers are an absolute MASTERPIECE if they're fake. The sheer number and the way they fade out would be ridiculously hard to fake unless the background was an extremely close match to the lake. Also, take a look at the direction and intensity of the lighting. It's spot on.
"I know what we can do to get famous on the Internets! We'll take a picture of us sitting at a pretty lake, and then we'll have a squirrel pop-up in front of us. We'll only have to look through 800,000 squirrel pictures to find one with the exact lighting and background we need!"
Her Facebook profile ( //www.facebook.com/people/Melissa-Brandts/770420491 ) has that picture for her profile pic. I'd say its real because the squirrels and chipmunks in the Canadian Rockies are absolutely fearless and quite curious about everything.
As for the lake itself, I've been out there a few times and it beautiful. I've yet to hike around it though. There is a nice loop to drive around. Its just outside the Banff townsite so if you get a chance to see it, it might be worth the trip. (Parts of the loop have been known to have black bears and wolves). Lots of wild flowers there too.
And if that's not enough of a plug check out dknourek's excellent image of the lake here:
(end of blatant plug)
Btw, it doesn't sound quite as funny as it reads, because it's pronounced minna-wonka... maybe a relative of Willy Wonka?
eta; I'm sure the photo's real. This is totally something a ground squirrel would do, especially in an area where they're acclimated to people. And look at the couple's reaction. They're laughing (or at least wearing big smiles) and it's a natural and spontaneous expression. It's not very likely they'd do such a good job of that if they were posing for a self-portrait with a P&S on timer.