Monday, January 14, 2013

The Snowy Owl of Ballard

Snowy owls silently swept south into Seattle again this winter.

(c) Pat Gaines/Creative Commons
On whispering white wings, the owls beat their way from the Arctic tundra in search of food, their flight muffled by feathery fringes that dampen sound. Here they perch on roofs and in trees, at airports and on beaches, keeping their counsel.

One of these owls has taken up residence in Ballard near Sunset Hill Park, a small patch of green with a sweeping view of Puget Sound and the Olympics. She perches in a tall Douglas-fir on some days, atop chimneys or roof slopes on others.

From this commanding position, she employs the "sit and wait" hunting technique of her kind, surveying her realm for the slightest movement of possible prey.

"She" has been identified as most likely being a young female due to the extensive dark-brown markings in her plumage. Young snowies are more heavily barred and spotted than older owls in general, but immature males tend to have paler markings than females and more of a white bib; females' brown markings can also be so dark as to appear black. According to the Cornell Lab of Ornithology, "any Snowy that looks nearly black and white is probably a female."

(c) Claire Thornburgh, used with kind permission
(Yes, Harry Potter fans, that means that Harry's owl Hedwig, at least in the movies, was actually a male [really three males, named Gizmo, Ook, and Sprout]. It's the males that grow up to have pure white plumage faintly marked with brown. The female owl, however, is bigger.)

Last year, I never got to see the owls who landed in Seattle as part of a nationwide irruption of snowies (an irruption that resulted in a snowy owl showing up in Hawaii for the first time ever).

I wasn't going to miss my chance this year, so I made sure to pop over to Sunset Hill Park several times.

I finally got lucky on one of those visits after learning that the thing to do was not to visit the park and look for an owl, but rather to drive up the street and look for the gaggle of people with telescopes and camera lenses aimed at the owl and join them.

That's when I saw her in all her chiaroscuro splendor, sitting calmly in an evergreen, dozing. Her closed eyes curved like crescent moons, making her look as if she were enjoying a quiet laugh. Occasionally she stirred and her eyes winked open, revealing the yellow full-moons behind her lids as she swiftly swiveled her head.

Irruptions of snowy owls typically occur every few years in response to cyclical fluctuations of lemming populations in the Arctic. If snowy owls had school cafeterias, lemmings would be their tater tots. These rodents form the bulk of their diet, and it's estimated that a typical snowy eats about 1,600 of them a year.

In lean years, when lemming populations are down (a result of lemmings gobbling up all the vegetation in boom years and then having to pay the piper, ecologically speaking), immature snowy owls are crowded off the  hunting grounds by older, dominant owls who claim the available territory. Hence the younger owls' nomadic forays into other climes.

Snowies aren't limited to lemmings, so they're not fussed about eating other foods in lemming-less lands. On the tundra, they also catch arctic hares, mice, ptarmigan, waterfowl, and even fish. (Indeed, its Swedish name is Harfang, which means "the owl that catches hares.") Elsewhere, they can subsist on a diet of ducks, gulls, rabbits, crows, rats, moles, and squirrels. They're not above scavenging roadkill, either.

(c) Petr Kratochvil/Public Domain Photos
Despite their size (about 2 feet long, with a 5-foot wingspan and a weight of up to 6 pounds), snowy owls move quickly--and the crows that sometimes mob Seattle's visitors are advised to keep their distance even from an owl that appears to be fast asleep. The 1936 tome Birds of America notes in its entry on the snowy owl that if a crow comes too close, "the ghost suddenly launches out on strong, silent wings, the great talons strike and close, and there is a Crow who would have been the wiser but for the circumstance that he is very dead."

The appearance of these ghostly birds far south of their usual winter range is nothing new. Native American peoples were familiar with the arrival of snowies and had their own speculations about why the white owls appeared. According to a  January 1965 article in The Milwaukee Journal about the deadly Blizzard of 1886, survivors of that storm recalled the "omen of the snowy owls. All through a warm autumn they came, ghosting through fog to roost in tall cottonwoods along the river. Indians warned settlers to expect bad weather, but few paid attention."

John James Audubon, writing more than a century before Alaska became part of the United States, knew about snowy owl irruption, too. He pointed out that "This beautiful bird is merely a winter visitor of the United States, where it is seldom seen before the month of November, and whence it retires as early as the beginning of February." He himself saw snowies in Kentucky and Ohio and notes that others popped up in Pennsylvania and New Jersey.

An 1887 "Cyclopedia of Natural History" recounts the circumpolar species' irruptions overseas. Snowy owls there are known for "occasionally straggling in winter to the British Islands, various parts of Central Europe, South Siberia, Mongolia."

The book's author was aware of North American irruptions, too, commenting that "Sometimes there is a large flight of them along the seacoast, so much of a one indeed that the fact is duly heralded in the local newspapers." In this respect, neither the owls' behavior nor that of newspapers has changed one whit.

Fortunately (despite the shooting of the wayward bird that landed in Hawaii), the snowy owls' reception has changed, thanks to laws that protect our native birds. Writing in the 1920s, naturalist William Dawson lamented that during an irruption "No opportunity is ever lost of killing one of these handsome midwinter visitors; and one might suppose, from the number of specimens which adorn store windows and taxidermists' shops, that the bird is much more common than it really is."

(c) Claire Thornburgh, used with kind permission
Sighting a snowy owl is not the only reward for visiting the Sunset Hill Park on a crunchy, cold, clear-sky winter day. The day I stopped by, I also saw an Anna's hummingbird buzzing in a bare treetop farther down the slope.

Few places, I imagine, offer a chance to see one of the world's smallest birds--a subtropical species that's expanded its winter range northward thanks to an abundance of feeders and nectar-rich exotic garden plants--with one of the world's largest owls, who's migrated southward from a land of ice and snow and not quite enough lemmings.

The hummingbirds are already starting their courtship and will soon be nesting. Some will be feeding nestlings by the end of February, by which time the snowies will have headed back to the tundra to start their own families.