Growing Up Snowy
Posted: March 5, 2018
Snowy owls came farther south this year than they have in quite a while. They were welcome visitors. Ornithologists and just-plain-curious folks got to see the fascinating creatures in real life. Maybe they went home and studied up on snowys. They might have learned about:
Male and female: Male: Males are smaller and pure white while females are bigger and store more fat to provide the energy for warming eggs. Females are also patterned for camouflage they need while sitting in the nest.
Getting together: When a male snowy owl wants to meet a female, he offers her a lemming. He claims territory. Two males might argue over territory, leaning toward each other, hooting back and forth and making dramatic flights. Snowy owls make ground nests on small mounds on the flat, frozen Arctic tundra.
Eggs: After a male and female snowy owl have been together, the female will lay about a dozen eggs. An embryo is developing in each—a growing tiny owl. The embryo is nourished by the fat and vitamins of the egg yolk. It gets water and protein from the albumen—the white of the egg.
Hatchlings: After the tiny owl has used up all the egg’s food and there is no more room for the tiny bird to grow, it uses a small, hard growth on the tip of its beak—its egg tooth—to chip its way out of the egg.
Week 1—Nestlings in soft, white down feathers are helpless. Eyes are closed. They can’t keep themselves warm. But in one week their weight triples.
Week 2—Eyes begin to open, gray secondary down feathers begin replacing white. Nubs of quills form on edges of wings where flight feathers will soon grow.
Week 3—Weight is near a pound. Birds are able to get out of the nest and stumble around.
Week 4, 5—Young owls toddle around outside the nest. This is actually safer than staying in the nest. If a predator finds the nest, it doesn’t find all the birds in one place.
Week 6, 7—Feathers get lighter with black spots, but much gray down remains. With no tree or cliff nest to jump from, fledglings learn to fly by doing a lot of wing-flapping and hopping into the air.
Week 8—Owlets have developed all layers of feathers. They’re becoming hunters and are able to fly for miles. Good thing, because the Arctic’s short season of warmth is gone and it is time to migrate south to winter grounds.
Did You Know?
An owl can’t rotate its eyeballs. But it can turn its head almost all the way around. The design of its blood vessels and spaces in its bone structure make this possible.
Snowy owls have more body fat than other birds. They can fast for up to a month if food is scarce.
In good years, snowy owls have been known to layer nests with dead lemmings—a fur-lined home!