[The Brandtses] had set the timer on their camera while posing at [Lake Minnewanka in Banff National Park in Canada].
Just as they were about to be captured on camera the cheeky squirrel popped up in the foreground and stole the show.
...Mrs. Brandts said: "We had our camera set up on some rocks and were getting ready to take the picture when this curious little ground squirrel appeared, became intrigued with the sound of the focusing camera and popped right into our shot."
The picture was submitted to the website of America's National Geographic magazine.
"It was a once in a lifetime moment - we were laughing about this little guy for days!" said Mrs Brandts. (link)
