A sow and her cub walk across a log on a small creek in Yukon, Canada, searching for salmon. Photo © Peter Mather

Wildlife and nature photographer Peter Mather had been photographing this creek in Yukon, Canada for years before he had an idea: set up a camera trap on a fallen tree. He figured grizzly bears would use the tree for salmon fishing, and thought it would be worth seeing what his remote camera could capture.

But even at his most optimistic, he didn't expect to capture a shot this good. A photo of a sow and her cub that would earn him recognition from National Geographic and a spot as one of the best wildlife images and a top spot in the Big Picture Natural World Photography Competition.

Mather tells DPReview the story behind the photo, in his own words:

For 3 years, I had been photographing salmon in this small creek that flows into the Yukon River. I was trying to get an over/under night photo of king salmon spawning under the northern lights, so I was out all night, every night in this salmon infested creek for a week.

I’d seen one grizzly in the creek. A young shy male. I figured that there weren’t many bears around, because the salmon stocks are plummeting and the area has been heavily hunted for bears. I knew of this great tree that fell on the side of the creek located 5 minutes downstream from where I was trying my salmon and northern lights photo, and I figured bears would use it to fish off, so I set up a motion detecting camera trap on it.

I left the camera for 3 days, when I returned I was ‘over the moon’ ecstatic to find this unique image of a sow and cub searching for salmon.

Scrolling through all the image, I was also a little freaked out to learn that there were 10 grizzly bears roaming the creek 5 minutes from where I spent my nights chasing the northern lights and salmon photo.

To see more of Mather's work—including that shot he was going for, the half-in half-out salmon under the Northern Lights—head over to his website or give him a follow on Facebook and Instagram.