Lemmings are the main prey of adult Arctic foxes in much of the tundra.
Arctic foxes are flexible predators, but lemmings often form the foundation of their tundra diet. Their numbers rise and fall in cycles, and fox breeding success frequently changes with the availability of these small rodents. In years with abundant lemmings, foxes may raise larger litters and cache surplus food.
Arctic foxes also eat voles, birds, eggs, fish, carrion, berries, and scraps left by larger predators. Around coastal areas they may scavenge marine mammals, while near polar-bear hunting grounds they can feed on leftovers from seal kills.
This varied diet helps the species survive when lemmings decline. The fox’s compact body, dense fur, and furred footpads reduce heat loss, while its coat changes color seasonally in many populations. The species is scientifically named Vulpes lagopus.