Nature Obscura. Kelly Brenner

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Nature Obscura - Kelly Brenner


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freshly painted.

      Anna in Winter

      Imagine, if you will, an animal that weighs the same as two dimes. This tiny creature has a heart that beats up to 1,250 times a minute when active. At rest, it takes 250 breaths a minute. Its tiny wings beat up to 200 times a second, which propels its flight to 30 miles per hour and hits 60 on a dive. This bird must consume at least double its body weight each day, and feed frequently during the day, or starve to death within a matter of hours. The food this animal consumes is nectar, supplemented with insects. It’s hard not only to find the time to eat constantly, but to find enough to eat. Now imagine having to find enough insects and nectar in the dead of winter, not in sunny San Diego, but in Seattle. This is the story of Anna’s hummingbird.

      Of the more than 320 species of hummingbird in the New World only 14 visit the United States. A mere four regularly make their way to Washington State and just two visit Seattle. But only a single species, the Anna’s hummingbird, can be found here throughout all the seasons. My yard is one of many that the Anna’s visit, and I watch them throughout the year. They are my constant companions—as long as I keep feeding them. If I forget to fill the feeders or go on vacation, they’ll abandon my house and visit one of the many others in the area that also provides feeders. I don’t take it personally.

      I’ve fed and watched Anna’s hummingbirds for well over a decade, from a small balcony near Portland to the small front yard of a rental house in Eugene, Oregon. Even while we lived in the middle of the city in Seattle, they found my lavender plants up on the sixth-floor balcony and visited regularly. Today, at our house in south Seattle, I feed them in both my front and back yards.

      Neither explorers Meriwether Lewis and William Clark in 1805 nor David Douglas in the 1820s ever encountered the Anna’s hummingbird. The birds didn’t live here when Washington became a state in 1889. They likewise missed out on the Alaska-Yukon-Pacific Exposition, the opening of the Smith Tower, the Spirit of St. Louis landing at Sand Point Naval Air Station, the collapse of the Tacoma Narrows Bridge, and the Seattle’s World’s Fair. Anna’s hummingbirds were not documented in Seattle until 1965, and it wasn’t until Luke Skywalker blew up the Death Star to cheers of audiences in 1977 that they started nesting here. These little nomads are not just increasing their range, however; they’re also increasing in number. The population of Anna’s has risen sevenfold in the Seattle area since 1990. A bird that just started breeding here the year I was born (1978) is now commonplace in my yard.

      It is thought that the Anna’s relatively sudden movement to Seattle is due in large part to an Australian tree, the eucalyptus. Along with tree tobacco, another non-native tree favored by hummingbirds, eucalyptus was introduced to Southern California somewhere around 1870 and quickly spread throughout much of the state, providing an ideal hummingbird resource in places previously bereft of nectar-producing plants in winter. The hummingbirds then expanded northward from their historic chaparral habitat of dense thickets of tangled, thorny shrubs in Baja California and Southern California.

      Simultaneously, humans moved into other areas historically devoid of nectar flowers and began dramatically altering those habitats by planting gardens filled with exotic, nectar-producing plants. Landscapes that had been previously unsuitable for hummingbirds were now capable of sustaining them, and thus began a historic change in Anna’s distribution. From California they moved steadily northward, following the landscape of flower-rich urban and suburban gardens into Oregon and shortly after into Washington. Although not yet directly studied, it’s currently believed Anna’s are entirely dependent on the feeders humans put out, along with the exotic flowering plants in this part of their current range. They rarely venture far from human settlements, living alongside us all year round.

      But who was Anna? The first official specimen of this little bird resided in the collection of one François Victor Masséna, the Duke of Rivoli. It was acquired courtesy of Paolo Emilio Botta, who collected it in San Francisco during his voyage aboard Le Héros beginning in 1826. Later, naturalist René-Primevère Lesson found the specimen in the Masséna collection while researching his book on hummingbirds and determined that it was a previously unknown species. He was the first to describe the new species and bestowed the name of Calypte anna, Anna’s hummingbird, in honor of Masséna’s wife, Anna de Belle Masséna.

      By all accounts the Duchess of Rivoli was a beautiful woman. John James Audubon himself was taken with her grace and beauty. And yet it’s perhaps ironic that this beautiful hummingbird was named for a beautiful woman because the female Anna’s hummingbird is a rather dull bird; it’s the male that has the resplendent ruby-red head.

      Male Anna’s hummingbirds rarely go unnoticed in our yard because they have evolved elaborate head decorations to attract the attention of females. A male Anna’s head is completely covered in bright, shimmering, gemstone-like feathers as if he’s wearing a shining helmet, and in fact Calypte is believed to derive from a Greek word meaning just that. Still, you’d be hard-pressed to find a helmet in any museum so extravagantly colored.

      Having studied the male that frequently perches on the feeder by my office window, I think it looks more like he is wearing a Mardi Gras mask. That’s because he has what’s called a gorget, named after the piece of medieval armor that protected the throat. Along the sides of his neck I’ve noticed the feathers sticking out on either side, so that, viewed from behind, it looks as if he has little wings on his neck.

      I can often tell when a female is near because the male will raise the feathers on the top of his head as well, adding to the Mardi Gras effect. Just to make absolutely sure the female doesn’t miss him, the male will move his head back and forth to catch the light on his iridescent feathers and then sing a complex song full of scratching chirps and squeaks.

      To us the female Anna’s may appear more homely, and when one visits my feeder I have to look closely to see her greatest extravagance: a trace of metallic red streaks on her throat. The dull colors greatly benefit the female Anna’s, who do their best to live their lives unnoticed. When females feed on nectar from flowers, their green backs blend in with the foliage; and when they sit on their eggs, the eggs are camouflaged by the birds’ green feathers.

      From my dining room window I watch the tiny hummingbird hover over the red feeder hanging from a suction cup on the window. It is an adult male, and before long he dives down to take a drink of nectar, or more specifically sugar water—four parts water to one part sugar—that I’ve brewed on the stove. Before I went to bed, I took the feeder down and brought it inside so the sugar water wouldn’t freeze when the temperature dropped that night. In the morning I put it back out as soon as I was up, and he was already waiting for me, arriving before I had the window closed. In winter I see hummingbirds at the feeders almost constantly. I often dine with them—myself at the dining table with a cup of steaming hot tea and a stack of chocolate chip pancakes, and the birds at the window feeder a few feet away drinking cold sugar water.

      It seems unfair that I’m so warm and comfortable inside as they fly around over the frosty grass and frozen birdbaths. Hummingbirds have to visit the feeders frequently because they’re at the extreme end of the vertebrate scale; they’re the smallest an animal can be. If the hummingbird’s minuscule body, no more than four inches long, was any smaller, it simply couldn’t eat enough to survive. Its tiny heart, the largest of all warm-blooded animals relative to body size, powers its flight. The pectoral muscles of a hummingbird, those responsible for flight, make up an astonishing 25 to 30 percent of the bird’s entire body weight.

      Hummingbirds use up more energy than any other animal relative to body size. To create that much energy, they must consume double their body weight in food and water each day, a task I help with by putting out feeders in winter and planting hummingbird-friendly flowers—those that are often red in color and tubular in shape—for spring and summer blooms. In my yard they frequently visit the orange honeysuckle, twinberry, red columbine, fireweed, and lupine. Hummingbirds are strongly attracted to the color red and are known to closely investigate people wearing red. The nectar, both human-made and natural, provides an energy-rich food source for them.

      Sometimes I watch them in the trees, buzzing around


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