These bighorn sheep are in Waterton Lakes National Park, Alberta. We traveled there in late April, right after an unexpected late-spring snowstorm. The snow covered the sheep's forage, and they were forced to dig through the snow with their hooves to find plants to eat.
To get this close, our stills photographer, Amanda McNaughton, and field assistant, Logan Turner, needed to find a way to approach the sheep without scaring them off or agitating the big rams that protect the herd.
They discovered that by imitating sheep behavior (hunching down on all fours, pawing the earth as if foraging for plants, making chewing motions with their jaws as if eating plants etc.) the sheep accepted their presence. Over the course of an hour Logan and Amanda slowly made their way across the hillside - pretending to be sheep themselves - until they were just metres away from the bighorns. It was painstakingly slow, and extremely cold (particularly digging in the snow with bare hands!), but eventually they got close enough to capture this intimate panorama.
The sheep are relaxed and behaving naturally, because they accepted Amanda and Logan as being fellow herbivores.