Tuesday, January 31, 2012

Summer's Hummers Are Winter's Glitter

Why it has taken me two decades to put up a hummingbird feeder, I cannot say. Miniature birds cloaked in dazzling jewel tones buzzing around like radio-controlled helicopters outside the living room window go a long way toward livening up a gray Northwest winter day.

It never ceases to amaze me that such a tiny puff of life can survive this far north in winter.

Seattle’s maritime climate generally soaks us in drizzle, mist, rain, fog, and all-purpose grayness for most of the winter (and a good chunk of autumn and spring)—not exactly the lush, warm paradise you’d envision for a hummingbird. Throw in a few subfreezing cold snaps and snowstorms, and you’d think the hummingbirds were goners for sure.

Instead, here we are, lingering over coffee, watching this iridescent creature sipping sugar water as snowflakes buffet its thumb-sized body.

When the female (at right) visits, she typically perches, feeds, then flies away. The male, however, tends to hang around between meals.

On this snowy morning, he alternated sips with perching on a limb of the red-twig dogwood, where he sat shaking his head, fanning his tail, and flicking his wings to shrug off snowflakes. It was hard to tell if the flakes were irritating him or if he was enjoying a shower—the actions were so much like those of a rufous hummingbird I’d seen bathing in a fountain last summer.

When he took refuge under the birdbath, however, it was clear that he wasn’t charmed by the snowflakes.

The sugar solution in the feeder (a standard 4 parts water/1 part sugar confection boiled, then cooled) stayed liquid until the temperature hit 29 degrees, at which point we brought it indoors to thaw.

While it was gone, the hummingbird continued to visit, hovering in the spot where the feeder normally hangs. He pirouetted around the empty space, as if the feeder would magically appear if only he viewed it from the right angle, forming question marks in the air with his flight patterns.

An awful image entered our minds at the thought of hummingbirds attempting to sip from a frozen feeder—an avian version of the tongue-frozen-to-a-pole scene from A Christmas Story.

Fortunately, “hummingbird tongue freezing” does not seem to be a problem recorded in the halls of birdlore, though some hummer fans sound an alarm about purported “perch hypothermia.”

("Perch hypothermia" is a supposed syndrome in which hummingbirds topple from perches after feeding on cold sugar solution, which supposedly wouldn’t happen if they hovered in front of the fake red flowers instead. I can’t help but feel there’s a strand of Protestant-work-ethic at work here: “Encouraging hummingbirds to be lazy and sit on perches is the work of the devil”).

Our visitor, by the way, is specifically an Anna’s hummingbird, a species that has expanded its winter range over the past 50 years. My decades-old Audubon bird encyclopedia notes that the Anna’s is the only hummingbird to winter in the United States and that it only nests in California; both statements are now false.

Hummers of other species, for example, are now known to winter in the southeastern states. The existence of exotic flowers in gardens as well as hummingbird feeders is reputed to have aided and abetted the expansion of hummers’ ranges, though it’s likely that other factors are driving it, too, and the increased presence of the hummers no doubt inspires the setting-out of feeders.

As for the Anna’s (which now ranges as far north as British Columbia), it even starts courting, nesting, and laying eggs in the northwest before the end of February. A midwinter walk is filled with hummingbirds’ squeaky conversations.

Photo (c) Alan Vernon, from Wiki Commons.
Last January I jumped out of my socks while admiring a female Anna’s perched low in a tree when a male hummingbird swooped in my face, wings whirring loudly, and shouted “PEEK!” in my ear, all in the snap of a second as he reached the bottom point of a courtship dive and then swooped upward again. It was as if someone had made a giant check mark next to my head.

Every time I see the hummingbird sitting quietly on his perch outside in the cold, I long to scoop him up and bring him inside to warm up, but he’s quite capable of enduring the chill despite having the fastest metabolism of any warm-blooded vertebrate animal (apparently even more frantic than that of a shrew’s).

At night, his heart rate drops from a typical 250 beats per minute to just 50 beats and he slips into a state of torpor. This ratcheting-down of his metabolism, combined with a crop full of nectar as a bedtime snack, enables him to survive an ice-cold winter night as long as he’s tucked safely out of the rain. It’s a tactic used by other hummingbird species, too.

According to naturalist William Leon Dawson, writing in 1923, even hummers living in tropical places go into torpor when conditions are bad: in Chile, a hummingbird “habitually weathers extended storms and bad nights in a comatose condition…Some perish in this fashion, but most of them revive with the returning sun.”

First thing in the morning, the little bird must surely anticipate a hit of “nectar” the way I do my coffee. Devoted hummingbird fans don’t settle for bringing in the feeder at night to avoid freezing and setting it out again in the morning—they’ve come up with ingenious ways of preventing freezing.

Their methods including hanging a “trouble light” near the feeder, strapping a hand warmer to it with duct tape (yay, duct tape!), cloaking it in heat tape, and stringing Christmas lights on it (though with the introduction of LED Christmas lights, this pretty ambient-heat solution will surely be phased out).

All this is a far cry from the way Thomas Nuttall, a naturalist friend of Audubon’s, treated a poor little female Anna’s when he happened upon her nest:

“My good friend Thomas Nuttall [writes Audubon], while travelling from the Rocky Mountains toward California, happened to observe on a low oak bush a Humming-bird's nest on which the female was sitting. Having cautiously approached, he secured the bird with his hat. The male in the meantime fluttered angrily around, but as my friend had not a gun, he was unable to procure it.”

I’d like to kick Nuttall in the shins for his action, never mind that he was advancing our understanding of the new world’s birds. Poor little mama bird, bravely guarding her bean-sized eggs, and her poor mate, zealously guarding her in vain! (The bit about the gun is astonishing: What on earth would be left of a hummingbird blasted with a shotgun?)

Most of the news of the day is guaranteed to make me feel that we’re going to Hades in a handbasket, but when I read accounts like this, I take heart that perhaps there’s a flicker of hope if our species is capable of going from catching nesting hummingbirds in our hats to decorating feeders with Christmas lights.