The Snowy Owl (Bubo scandiacus) is a large, almost entirely white owl of the high Arctic that breeds on bare tundra and depends heavily on the boom-and-bust cycles of lemmings. It measures roughly 53–66 cm in length with a wingspan of 125–150 cm. Males are nearly pure white, while females and young birds carry much denser dark barring across the back, wings and breast. The head is round with no ear tufts, the eyes are bright yellow, and the bill is largely hidden beneath white feathering; even the legs and toes are densely feathered against the cold. Its size, white plumage and habit of hunting in daylight make it hard to confuse with any other Scandinavian owl.
Snowy Owls are mostly silent outside the breeding season, though males give a deep, powerful hoot at the nest and both sexes bark and cackle when defending their territory. In Sweden the species sits at the southern edge of its range and breeds only irregularly in the alpine tundra of the northernmost mountains; the number of nesting pairs swings wildly from year to year depending entirely on rodent abundance, and breeding can fail completely in poor lemming years. The nest is a shallow scrape on a dry, elevated spot with a clear view of the surroundings, and clutch size tracks food supply, reaching close to ten eggs in the best years while females incubate and males aggressively defend the territory against predators and approaching humans. Lemmings and voles dominate the diet, supplemented by birds and other small animals when rodents are scarce, and because the Arctic summer brings round-the-clock daylight this owl often hunts by day rather than at night. Globally the species is classified as Vulnerable, and outside its irregular mountain breeding range every Swedish sighting is treated as a notable event among birders.
Read about this species in Swedish →