Snowy Owl

About the snowy owl

The snowy owl, also known as the polar owl, white owl, or Arctic owl, is a large member of the true owl family and one of the biggest owl species alive. It's also the only owl with mainly white plumage, which makes it instantly recognizable even at a distance — in the field, a resting snowy owl can look like little more than a pale rock or a lump of snow on the ground. Males tend to run purer white, while females carry more extensive dark brown flecking, and juvenile males show dark markings that can make them resemble females until they mature. The pattern of brown markings on the wing is the most reliable way to age and sex an individual bird, though it isn't foolproof.

Native to the Arctic regions of both North America and the Palearctic, the snowy owl breeds mostly on the open tundra. It was first described by Carl Linnaeus in 1758, and for much of its taxonomic history was treated as the lone member of its own genus, Nyctea. Genetic testing eventually tied it closely to the horned owls of the genus Bubo — its closest living relative turns out to be the great horned owl — though some researchers still argue for keeping it separate on skeletal grounds. The fossil record shows the snowy owl once ranged much farther south, into what's now Austria, France, Germany, Spain, and parts of the Americas, during past glacial periods.

Physically, the snowy owl's head is relatively small with a shallow facial disc, and its ear tufts — usually invisible — measure only about 20 to 25 mm (0.79 to 0.98 in) when raised, most often by a female sitting on the nest. Its eyes are bright yellow. The toes carry the longest feathering of any owl, averaging 33.3 mm (1.31 in), well ahead of the great horned owl's 13 mm (0.51 in), while the claws beneath are black. Unlike many other whitish birds, the snowy owl lacks black wingtips — a feature theorized to reduce wing-feather wear in those other species.

Behavior and diet

Unlike most owls, which sleep by day and hunt at night, the snowy owl is often active during daylight hours, especially in summer. It hunts as both a specialist and a generalist: breeding success and overall population numbers track closely with the availability of tundra lemmings, but outside the breeding season, and sometimes during it, the owl adapts to whatever prey is around, most often other small mammals and northerly water birds, along with carrion when the opportunity arises. It hunts by hovering occasionally despite its size, and its flight is steady and direct, drawing comparisons to a large, slow-flying falcon; it doesn't appear to soar. The flight has some of the sound-dampening wing serrations typical of owls, but fewer than related Bubo species, so it can be audible at close range — unusual for an owl.

Snowy owls typically nest on a small rise on the open tundra, and lay unusually large clutches for a raptor, often five to eleven eggs, with laying and hatching noticeably staggered across the clutch. Given the short Arctic summer, chick development takes a relatively long time, and young owls don't gain independence until autumn. The species is nomadic, rarely returning to the same nesting site or mate from year to year, and it often skips breeding entirely in years when prey is scarce.

Range and habitat

The snowy owl breeds across the Arctic tundra of both North America and the Palearctic. It's a highly migratory bird that can wander almost anywhere near the Arctic outside the breeding season, and it's known for occasional large, unpredictable irruptions southward when conditions push it to search farther afield for food. That nomadic, wide-ranging behavior has made the species notoriously difficult to survey consistently, so long-term population data has historically been thin.

Conservation status

The snowy owl is listed as Vulnerable. Population estimates have shifted sharply: the global population was once put at over 200,000 individuals, but data from the 2010s and 2020s suggests fewer than 100,000 remain, with successful breeding pairs numbering around 28,000 or possibly considerably fewer. The exact causes behind the decline aren't well understood, but a range of complex environmental factors linked to global warming appear to be central to the pressure the species now faces.