Snowy Owl
| Scientific Name | Bubo scandiacus |
| Survival Strategy | Medium-distance migrant to long-distance migrant |
| Arrival in Upper Midwest | November |
| Departure | Late April |
| Summer Range | Arctic Tundra |
| Conservation status | Vulnerable |
Spring
Snowy owls begin to move north to their breeding grounds in March or April, with most arriving on the tundra by mid-April through May. Breeding pairs will claim a dry elevated area as a nest site. The female will lay 3 to 8 eggs in mid-May to early June and incubate them for 32 days.
Summer
Owl chicks will fledge at seven to eight weeks of age and be independent of adults by late August.
Fall
While most overwinter on the arctic tundra, some snowy owls, mostly younger birds, migrate south. Reports of snowy owl sightings in the upper Midwest begin in mid-November.
Winter
Snowy owls are unpredictable and sporadic winter visitors to the Midwest.
Behavior
Diurnal and Nocturnal Hunters
Out of necessity, snowy owls hunt in both daylight (diurnal) and darkness (nocturnal). This flexibility is necessary because, in the high latitudes of the Arctic, these owls will experience 24 hours of darkness in the middle of winter and 24 hours of light in the middle of summer.
Irruption, not Eruption
While many snowy owls will remain in the Arctic year-round, others migrate to areas with more abundant food sources available. An irruption of snowy owls occurs every few winters in the Midwest. During summers with high lemming populations, snowy owls have great nesting success, and their population increases. Older territorial owls drive off younger owls as the deep winter snow reduces available food. Biologists once thought these birds were near starvation, but recent studies have found most of these visitors are in good health.
Sailors have reported migrating snowy owls hitching a ride on ships in the Atlantic Ocean and the Great Lakes. Satellite tracking data indicates that snowy owls can move hundreds of kilometers in a few days, then stay put for an extended period.
Physiology
Feather Patterns
Snowy owls range in color from white to mostly white with dark bars. Females are typically larger and have more dark markings than males. Hatch-year owls have dark markings similar to an adult female.
Built for Cold
Snowy owls have many adaptations that allow them to survive some of the coldest temperatures on Earth. They are round-bodied, which creates a surface-area-to-volume ratio that insulates efficiently (less surface area/more volume). Fur-like feathers cover their face, beak, legs, and feet.
Diet
Snowy owls feed on rabbits, voles, lemmings, and waterfowl.
Lifespan and Mortality
The average lifespan of snowy owls is ten years.
Predators
Foxes and wolves will prey on adult owls at a nest site, and jaegers will prey on unattended eggs and chicks.
Climate Vulnerability
As Arctic summers become warmer, summer prey’s abundance may increase winter irruptions in the lower 48 states (see Behavior above).
Never stop learning
Movie Trivia: Harry’s owl Hedwig is a female snowy owl in the Harry Potter films. Seven different owls played the role of Hedwig, and they were all male. Only male snowy owls have pure white feathers. The animal actors’ names are Gizmo, Kasper, Oops, Swoops, Oh Oh, Elmo, and Bandit.
Anthropology: A paleolithic painting of a snowy owl adorns the Chauvet Cave wall of Ardèche, France, that dates back 30,000 years.
First Nations: In Iñupiaq, the native language of the Inupiat people, snowy owls are called “Ukpi.”
References
| Holt, D. W., M. D. Larson, N. Smith, D. L. Evans, and D. F. Parmelee (2020). Snowy Owl (Bubo scandiacus), version 1.0. In Birds of the World (S. M. Billerman, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.snoowl1.01 |
| Project Snow Storm https://www.projectsnowstorm.org/ |
| Cornell Lab of Ornithology: Snowy Owl Invasion (video runtime 3:38) https://youtu.be/Ufkcx-UqljM |
| The IUCN Red List of Threatened Species: Snowy Owl https://www.iucnredlist.org/species/22689055/127837214 |
| Secrets Of The Snowy Owl | NPR’s Skunk Bear (video runtime 8:32) https://youtu.be/HXwrB216bgE |
| Magic of the Snowy Owl-Infographic: All About Snowy Owls https://www.pbs.org/wnet/nature/magic-of-the-snowy-owl-infographic-all-about-snowy-owls/7962/ |
| The Inupiat People – Kikiktagruk Inupiat Corporation https://kikiktagruk.com/shareholders/ |