Espen Bergersen / Red fox (Vulpes vulpes) searching for lemmings buried in deep snow. Lapland, Finland, March.

Erlend Haarberg / Norway lemming (Lemmus lemmus) calling on spring snow, Vauldalen, Norway, May

Erlend Haarberg / Two Norway lemmings (Lemmus lemmus) interacting on spring snow, Vauldalen, Norway, April

Erlend Haarberg / Norway lemming (Lemmus lemmus) swimming, Sweden, May

Bengt Lundberg / Norway lemming on snow {Lemmus lemmus} Sweden

Espen Bergersen / Red fox (Vulpes vulpes) feeding on frozen lemmings buried in deep snow. Lapland, Finland. March.

Espen Bergersen / Red fox (Vulpes vulpes) feeding on frozen lemmings buried in deep snow. Lapland, Finland. March.

Markus Varesvuo / Hawk owl (Surnia ulula) hunting lemmings in the snow. Liminka, Finland.

Sergey Gorshkov / Arctic fox (Vulpes lagopus) in summer coat with lemmings in mouth, Wrangel Island, Far Eastern Russia, August.

Sergey Gorshkov / Arctic fox (Vulpes lagopus) in winter fur hunting for lemmings, Wrangel Island, Far Eastern Russia, October.

Sergey Gorshkov / Arctic fox (Vulpes lagopus) in winter fur hunting for lemmings, Wrangel Island, Far Eastern Russia, October.

Sergey Gorshkov / Arctic fox (Vulpes lagopus) in winter fur hunting for lemmings, Wrangel Island, Far Eastern Russia, October.