Snowy Owls

Ecology, Habits, and Other Fun Facts

Basic Facts

  • Scientific Name: Bubo scandiacus
  • Nicknames: Great White Owl, Arctic Owl, and Ookipk
  • Lifespan: 9.5 years in both the wild and in captivity
  • Status: Declining, but not yet endangered
  • Diet: Lemmings (3-5 per day, over 1,600 per year), arctic rabbits, various rodents, other smaller birds, and some fish
  • Populations: Populations fluxute with the lemming population, Estimated at around 290,000 individuals... is very hard to accurately measure this because of the large population area
  • Habitat: Mostly in the northern arctic, but snowy owls normally migrate with the lemming populations
  • DNA Facts: Snowy owls have 82 chromosomes (basically DNA units for storage), which is 36 more chromosomes than the much more complex humans have
  • Other habits: Diurnal, perches and waits for prey, lays clutches of 3-11 eggs at a time

The Capturing of Energy

  • Consumption: Snowy Owls are carniverous; they only eat meat
  • Trophic Level: Snowy owls are secondary consumers... this means that they eat herbivores, for the most part. Tracing the trophic pyramid to the roots, we come to the autotrophs... the autotrophs only need sunlight to make their food. Therefore, the sun is the ultimate source of energy in this ecosystem, and all other living things get their energy from different conversions of the sun's energy.
  • Area needed to support diet: Snowy owls will travel wherever the lemming population moves to support their diet... will go across the Arctic, North America, Europe, and even parts of Asia

Relationships in the Ecosystem

  • Mating habits: Snowy owls are monogamous, sexual reproducers... they do not breed during hard times and are fiercely loyal to their partners, children, and territory. Because they sexually reproduce, they get more genetic variation in their offspring.
  • Competition: Snowy owls are often in competition with wolves for food, as well as protecting their young... some predators, such as the jaeger, also prey on snowy owl eggs to eliminate offspring.
  • Population growth: The snowy owl population grows and shrinks with the lemming population.
  • Predators: in times of scarce food, wolves and arctic foxes may prey on weaker owls. Also, some jaegers and skuas may feed on unhatched eggs of snowy owls. Otherwise, snowy owls are apex predators of the arctic.
  • Threats: The main threats in this ecosystem are airborne pollutants, oil and gas developments, and global warming. These abiotic factors greatly affect all of the living (biotic) things in this ecosystem, even though they do not live in the ecosystem, per se.
  • Keystone/indicator species: In the arctic, keystone species are arctic hares. Indicator species include reindeer, caribou, arctic tundra wildflowers and arctic lichen. Beings such as this contribute to the overall biodiversity of the arctic, keeping the tundra balanced and healthy.
  • A Note About Speciation: By definition of speciation, snowy owls cannot successfully reproduce with other species of owls... this is important to remember when talking about a specific species of snowy owls.
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Evolution, Ancestry, and Other Changes

  • Selective Pressures for Adaptation: White and brown plumage, enhanced hearing, diurnal behavior, and long, sharp talons help snowy owls to camouflage in the snow, have better senses to hunt, have better ability to hunt, and have more time to hunt and reproduce. It seems that once this happened by some series of genetic mutations during meiotic cell division, the mutations ended up benefitting the organism. Because the mutation was favorable to this organism, natural selection eventually made snowy owls who they are today and weeded out the "old version" of this species in this area.
  • Speciation: There is very little evidence for why the owl experienced speciation to become the snowy owl. The best hypothesis is that a northern species of an owl was separated by a glacier, and the owls on the northern, cooler side of that glacier had to adapt to live in the cooler weather.
  • Evolution: It is widely accepted that the first owls evolved from the Tyrannosaurus Rex dinosaur. From there, 3 subspecies of owls developed; ninoxinae, surniinae, and striginae. From there, the striginae family continued to speciate to the bubonini family. The bubo species then came along, and this is where the snowy owl falls into its evolutionary tree! To be even more specific, the snowy owl's last known related species is the Great Horned Owl. As the organism's mutated DNA kept being passed on to its offspring, the snowy owl evolved.
  • Co-evolution: There is a lot of evidence that most of the snow-white animals in the arctic tundra evolved at the same time to be that way. The arctic hare, snowy owl, polar bear, and arctic fox likely evolved to become white like they are in the same process, when their environment became permanently... frosty.
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References

"Basic Facts About Snowy Owls." Defenders of Wildlife. Defenders of Wildlife, 19 Mar. 2012. Web. 28 May 2016.


Buchanan, Jeremy. "Tundra." Coevolution Mechanisms. Blogger, 10 Nov. 2011. Web. 28 May 2016.


Canadian Museum of Nature. "Food Web." Ukaliq: The Arctic Hare. Canadian Museum of Nature, 2004. Web. 28 May 2016.


Cornell University. "Snowy Owl." Life History, All About Birds. Cornell University, 2015. Web. 28 May 2016.


Graber, Richard R. Food and Oxygen Consumption in Three Species of Owls. 28 Mar. 1962. A PDF report about owls. Illinois State Natural History Survey Division, Urbana.


Lewis, Deane. "Snowy Owl (Bubo Scandiacus)." The Owl Pages. The Owl Pages, 17 Oct. 2015. Web. 28 May 2016.


National Geographic. "Snowy Owl." National Geographic. National Geographic, 2016. Web. 28 May 2016.


Pena, Kelly. "Arctic Owls." Arctic Owls. Weebly. Web. 28 May 2016.


"Snowy Owl." Home. The Alaska Zoo. Web. 28 May 2016.


"A Table of Arctic Animals." Arctic Animals Habitat, Diet and Insulation. University of East London. Web. 28 May 2016.


"The Tundra Biome." The Tundra Biome. Marietta College. Web. 28 May 2016.


"Threats." Defenders of Wildlife. Defenders of Wildlife, 19 Mar. 2012. Web. 28 May 2016.


University of Calgary. "Caribou Anatomy." Caribou Anatomy. University of Calgary, University of Saskatchewan, 2011. Web. 28 May 2016.