Have you ever wondered how wild animals cope with winter weather? The winter-season storms are merely another outdoor challenge for many of nature's creatures.
One of the most-fascinating animal adaptations to the cold season is the story of how the tiny Anna's Hummingbird manages to survive in the winter chill of the Sierran foothill country. Throughout central California, from the Feather River to the ocean, the determined, diminutive, nectar-seeking bird is able to maintain a certain population - and, indeed, manages to nest in midwinter when other hummingbird species migrate south to warm climates!
Down by the riverside one fog-chilled December morning, I was reminded of the Anna's character as a male was displaying courtship gestures. Up, up, up, into the sky until merely a speck, and then that breathtaking plunge downward with a last-second stop inches from its shrub perch. It was showing off for some lady watching nearby and establishing intentions of doing the family thing ... soon ... regardless of the emerging winter solstice and potential ice storms. The Anna's Hummingbird and the Great Horned Owl have something in common - they both can be found nesting in California woods in January!
Anna's Hummingbirds build that thimble-sized masterpiece to hold their two tiny pearl eggs, and they attach it to some sturdy limb, or even to structural improbabilities such as under our patio on the bolt of the porch swing one year! That pair succeeded in raising one baby even though a rat climbed the chain, took a baby, and left the nest torn. Hummingbirds will chase eagles away from their nesting vicinity, but rats are something else.
A bird that depends on flower nectar finds it necessary to locate blossoms or sugar-water feeders that many kind-hearted bird lovers maintain during the winter. Fortunately, it stays just warm enough for hardy flowers to bloom throughout December and January around Oroville, including the introduced red-flowered eucalyptus that grows along the Feather River Parkway Path. The Australian native Eucalyptus sideroxylon trees follow the gene instructions of their homeland, and erupt in lavish outputs of frilly flowers during the coldest weather. As many as two dozen hummingbirds can be found foraging in nectar fairyland at the one levee location near the Oroville Auditorium.
One foggy day I drove upon the mountainside to where the sun was shining, taking an automobile flight like a bird to rise above the foggy sea that can linger for days in the lowlands.
Up at 2,000 feet, I searched in the sun for quartz crystals and mushrooms where it was almost springtime warm in the sheltered nooks along the hill and 15 degrees warmer than down there in the cloud that hung tightly to the valleys. Even as the birds and deer were lulling in the warm glow, that ominous mist monster started crawling up the mountainside, sending the wildlife into hiding and striking my cheek with a cold sting.
Suddenly the sun was gone, slowly disappearing into the engulfing fog grayness like a space disc fading out of sight into the heavens. Silently the fog had again gained strength and was claiming higher territory, even as I hastened to the car. There were no hummingbirds in those higher oak woodlands where turkey and deer thrive on the acorns. A bird must be free to choose what best fits, and hummingbirds know the chances of finding food and shelter are better along the river.
Winter is seemingly more suitable for seed eaters than for insect hunters or nectar seekers. Yet, a few insect-eating Black Phoebes sick around the Feather River in winter, knowing that, down low, a few flies will arise in sheltered nooks. Just enough to keep a few birds alive. One Audubon Christmas Bird Count in Butte County even produced a few Tree Swallows one winter! The great thing about nature watching is that there are always surprises and exceptions to the rules!
When we look at those small birds clinging to barren branches or see the sparrows hopping on frosty lawns, we marvel at the adaptation that allows them to survive during adverse weather. There is even greater wonder in the way waterfowl can sit on ice-cold water all day and stay warm enough to live. You see the diving ducks on Lake Merritt and San Francisco Bay rafting on the frigid surface, and you wonder how they do it.
One winter the ponds at Gray Lodge Wildlife Area partially froze, but the ducks hung around unfazed by the icy coating. The dabbling ducks that can walk on land thrive even amid ice if food is available. That same winter, the freshwater duck pond at Lake Merritt froze over and Mallards would fly in for a skid landing, and then walk around looking at their reflection in the ice as if amused or dazed. No wonder the diving ducks, that have difficulty in using their rear-set legs on land, concentrate on iceless saltwater locations.
The hardiness of birds is especially apparent in my home state of Missouri, where icy storms can coat the forest with frozen arms - not only limiting food supplies, but putting stress on those high-temperature bodies. You get a special pang of sympathetic feelings when viewing a cardinal perched in leafless branches of a snow-white world. The tiny junco snow birds scratch the thickets seeking sustenance for sustainment until better times.
How do they do it? How do they repel the elements to flourish, often to the point of exuberant song even during oncoming storms? Bird sounds can be heard throughout the winter in the timbered hills of the Midwest, and their endless activity instills an aliveness to the out-of-doors that is both heartening and inspirational.
How delightful it is to hear the titmouse repeating its pet phrase over and over again as it explores the silver maple over my house. I know if I go up on Yellow Creek in the mountains even in December, I could hear the American Dipper singing from its rock in the rapids. The expectation of such natural joys on earth is the lifeblood of the nature watcher.
How do they do it? How do water birds and the snowbirds stay warm? Birds survive through the ingenious construction of the feather. Those frail-looking appendages that both bless the bird with flight feathers and also provide an encasement of downy fluff for warmth, unite together to enable all bird species to survive.
Take a close look at a feather sometime. A swan is covered with about 25,000, and they are replaced every year during the molt. There are several different types of feathers on each bird, but they all feature microscopic hook structures that help them cling together. Birds can often be seen preening the feathers into shape and coating them with an oily film they produce.
In the Christmas wondertime of man-made glitter, there also are many natural winter wonders, and the wonders of just one feather would fill a book.
© 2000 Rex Burress
December 7, 2000