A pair of snowboarders were surprised when an unexpected animal chased after them on the slopes at Jackson Hole Mountain Resort in Wyoming: a moose.

One of the snowboarders, Scott Askins, was taking a video of a friend performing a frontside boardslide about a week ago when a moose walked onto the slopes. The animal bolted after them. Askins kept filming while he and his friend snowboarded down the mountain. The moose eventually stopped long enough for the snowboarders to put some distance between themselves and the animal.

As the largest of all the deer species, moose are typically between five feet and six and a half feet tall. Their antlers can spread up to six feet across and they are very nimble on land, with the ability to run 35 miles an hour for short distances. A moose’s hooves act as snowshoes on soft snow, distributing their weight evenly. They can weigh an average of 1,800 pounds.

It’s unclear why the moose approached the snowboarders. The Colorado Parks and Wildlife agency’s website says that moose don’t have many natural enemies, so they aren’t as afraid of people as other big game species often are.

The state website advises people to be aware of moose behavior when visiting areas they inhabit, including protective female moose who can be dangerous when caught off-guard and male moose who can be aggressive and territorial (particularly during the fall mating season).

Unlike with bears, it's okay to run away from a charging moose, the National Parks Service says.

Moose are very curious animals and will sometimes approach people, houses, or cars. They have been approaching cars in Alberta, Canada, this winter to lick salt off of the vehicles. This may also explain why the moose at Jackson Hole ended up on the slopes—it may have just been curious about the people zooming quickly down the mountain.