I do not know what the moose below was running from — or towards — but I would be wary of both.
A few quick moose facts for you before the video:
The moose is the largest member of the deer family. An adult male averages 6-feet tall at the shoulder. It can also weigh as much as 1,400 pounds. A moose can carry up to 100 pounds of food in its stomach. It also grows a new set of antlers each year, which can be as much as 4-5 feet wide and weigh 30 pounds.
All those are pretty mundane, maybe even known. How about this: A moose can run 35 mph.
There is zero chance that you want to mess with a moose. You probably also do not want to know what caused this moose to plow through three-feet of snow at full speed. The people just standing there watching, calmly shooting a video, could be in trouble.
With their massive size, strength, and speed an adult moose has very few natural predators. Large bears, and packs of wolves, will sometimes take down the animal but most of their deaths come from car accidents or natural causes. It could just be flexing for the camera or it could be running from an avalanche or something.
That particular moose is moving snow like a train plowing the tracks through the Donner Pass!