Few people know hummingbirds as intimately as Bill Calder. He's held thousands of them in his hand, where the birds lie still except for the pulsing of their iridescent breasts. He's felt the brush of their wings, like eyelashes fluttering against his skin.
And once, as Calder sat watching a feeder through an open window, a hummingbird flew into his open mouth. Then he felt the touch of its tongue on his, like a strand of angel hair pasta.
"I was genuinely French-kissed by a hummingbird," Calder said.
That bird kissed and flew, but Calder's love of hummingbirds is more than a passing infatuation. The professor and bird researcher has studied hummingbirds for 34 years, following rufous hummingbirds on their 2,600-mile migration from southern Mexico to Southeast Alaska and back.
"Virtually everything that's known about this bird is from his work," said Michael Carter, executive director for the Rocky Mountain Bird Observatory.
One of the things Calder is trying to discover is the role rufous hummingbirds play in the areas they pass through. The nectar-feeding birds pollinate plants along their flight path, making them a potentially important link in ecosystems from Arizona's Sonoran Desert to the Tongass rain forest, Calder said. Rufous hummingbirds are one of four migrating pollinators being studied in an international research program.
But in annual bird counts the number of rufous hummingbirds has been dropping, to the point that the Audubon Society added the species to a Watch List of birds needing conservation measures. Though the hummingbirds' migration is long, breeding and wintering grounds are relatively limited, Carter said.
"If something bad just happens in that area then the bird can be at risk," Carter said. "If disease hits or a hurricane or something like that, a really bad winter."
Rufous hummingbirds also take a long time to recover from any blow to their population, since each female usually only raises two chicks in her lifetime. A drought in Mexico, an out-of-season snowstorm in Colorado or anything else that harms the supply of flowers and insects could change the population of rufous hummingbirds reaching Juneau each summer. That, in turn, could affect the wild blueberry crop, which feeds other birds, bears and people.
"Usually we think of 'This is endangered' and 'This is endangered,' but what's really important is the relation," said Calder, a research associate of the Arizona Sonoran Desert Museum Migratory Pollinator Conservation Program and professor in the Department of Ecology and Evolutionary Biology at the University of Arizona in Tucson.
Calder sometimes catches hummingbirds with telltale streaks of pollen ringing their faces. The western columbine, Indian paintbrush and other flowers have adapted to be pollinated almost exclusively by hummingbirds. In Southeast Alaska, bird expert Bob Armstrong suspects rufous hummingbirds are a prime pollinator of the wild blueberry - often the only flower blooming when the birds first arrive in early April.
Author of "Alaska's Birds: A Guide to Selected Species," Armstrong and research ecologist Mary Wilson are studying just how important rufous hummingbirds are to blueberry plants. Early in the spring they wrapped a number of blueberry bushes near Armstrong's home in varying sizes of mesh, designed to selectively keep out hummingbirds, bees and other insects. Later this summer they'll count the berries to see which bushes were most successful.
Armstrong's Thane property is the best place Calder's found in Juneau to trap and study hummingbirds and he makes it part of his annual research migration. On a gray June afternoon rufous hummingbirds darted back and forth over Armstrong's waterfront deck, streaks of rusty red. Five, six, seven of them hovered momentarily outside the window, then disappeared in different directions. Many of them are females returning to their nests. They were replaced by several others at the one-quart feeder Armstrong refills every a day.
"You can put your finger in front of the feeder and they'll land on your finger. You barely feel them, just a little pin prick." Armstrong said. "They're very light, about the weight of a stick of chewing gum. You hardly know they're there."
Calder set mist nets on Armstrong's deck to catch the hummingbirds. Each one was weighed, recorded and tagged with an aluminum ring the size of a single link in a chain necklace. He plucked two tail feathers from each bird to run DNA analysis, then let it go. His hope is to run into the same birds again someplace else, so he can map exactly what path the rufous hummingbirds follow in their migration. One hummingbird tagged in Ketchikan was recaptured in Colorado. But since the birds are so tiny and the area is so large, recapture is rare.
While Calder's been following the rufous hummingbirds, their migration has begun to change and spread. They're moving into the southeastern United States in the winter, showing up in Georgia, Alabama and North Carolina. Some are also working their way farther north in the summer, occasionally turning up in Fairbanks.
Already the hummingbirds' migration was remarkable for such a tiny bird. Measured in straight distance, the arctic tern flies farther than any other bird, 20,000 miles from feeding grounds in the Antarctic to breeding grounds in the Arctic. But any child will tell you distance is relative to size. An adult's short walk is a 4-year-old's marathon.
Measured in body lengths, the 3.5-inch rufous hummingbird migrates the equivalent of 48 million body lengths from Jalisco and Oaxaca, Mexico to Southeast Alaska and back. That would be the same as a 5-foot-6 person circling the globe twice. The 15-inch Arctic tern's long journey is only 46 million body lengths.
"These are the boldest explorers, coming up to the Last Frontier," Calder said.
The birds also cross the Sonoran Desert. On particularly dry years, when Calder finds few flowers in the desert, he also finds few hummingbirds. The ones he does catch are so low in body weight he's unsure they will make it out of the desert.
"If we jack up the temperature another notch, they could be doing better further north or doing worse further south," Calder said. "Because of their metabolic needs, they could be a bellwether (for global climate change)."
The allure of the hummingbird goes beyond its scientific interest. People love hummingbirds.
"They're colorful," said Sandy Skrien, organizer of the Hummingbird Festival held in Ketchikan each April to celebrate the return of migratory birds. "They're just the kind of bird that everybody likes."
She keeps four hummingbird feeders in her own yard, and usually puts a bucket of blueberry bush branches on her deck around Easter. The birds hide in the blueberry twigs between trips to the feeder, she said.
Even for Calder, who handles the hummingbirds with nonchalance born of familiarity, there is something almost mystical about the birds. Holding bird No. 144 a few weeks ago at Armstrong's house, he looked backwards through his binoculars to gaze into her magnified brown eye.
"If you look in the middle of her eye," he said, "you can see the center of the universe."
Kristan Hutchison can be reached at firstname.lastname@example.org.
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