Arctic Foxes are about as clever as any creature of the tundra! They adopt both scavenger and predator diets, depending on conditions. As predators, they can locate--and catch--small animals hidden deep under the snow! They hunt in any terrain in their habitat though--including volcanic terrain.
If they aren't hunting their favorites--lemmings, voles, and such--they might be following polar bears across the northern sea-ice to scavenge. Successful scavengers are big-time opportunists: this Fox on the Rocks in the photo below is patrolling the coasts of the Pribilof Islands near Alaska.
You can find these guys anywhere north of the tree line in Arctic tundra, throughout Eurasia and North America. In some places, the Arctic Fox is a treasured legacy of pristine nature--for instance, it is the only land mammal native to Iceland.
Arctic Fox serenade
Hornvik, Hornstrandir Peninsula, Iceland, July 2012. A wild fox (terribly shy of people, as you can see) came up and treated us to this concert.
Where they are not protected, there are rescue centers that will take in Arctic Fox kits orphaned by hunting, disease, competition with rival Red Foxes, or chemical contamination. "Freddy" here is a rescue from the Arctic Fox Center in Iceland.