From Wikipedia:

Santa is native largely within the Arctic Circle encompassing the Arctic Ocean, its surrounding seas and surrounding land masses. He is the world’s largest land carnivore and he weighs around 350–680 kg (770–1,500 lb). Although he is closely related to the Dutch ‘Sinterklaas,’ he has evolved to occupy a narrower ecological niche, with many body characteristics adapted for cold temperatures, for moving across snow, ice, and open water, and for hunting the seals which make up most of his diet. Although Santa was born on land, he spends most of his time at sea. Santa can hunt his preferred food of seals from the edge of sea ice, often living off fat reserves when no sea ice is present.