Leslie T. Sharpe

One Planet

A Passion for Bluebirds

The bias of beauty.

Posted Aug 02, 2018

Naturelady/Pixabay
Source: Naturelady/Pixabay

The first thing I did when I came to the Catskills was put up nesting boxes in the meadow. I hoped to attract bluebirds, those pretty little songsters, and I was thrilled when a pair tenanted a box that summer.

I watched as the female built her nest, meticulously carrying strands of pale dried grass into the box. At day’s end, the male entered the box to inspect his mate’s work, evicting a suspect strand or two, then sat in the yellow cedar tree, serenading the female with his sweet, melodious “toura-loura-loura” song.

Mama was a tireless worker, plying her hatchlings with beetles, butterflies, and crickets. Papa was a dreamer, sitting with a wriggling worm in his bill atop the flagpole until Mama nudged him and he flew to the box to feed his hungry offspring.

I quickly grew addicted to watching the bluebirds, impressed by how hard they worked, touched by their devotion to each other and especially their nestlings, feeding them from dawn to dusk. Bluebird parents always feed their young first, flying as far as 70 miles in a single day to find food, in the cold, forbidding weeks of early spring.

My day soon became defined by “my” bluebirds. “My” bluebirds... I was breaking the naturalist’s first rule—never sentimentalize critters, never confuse instinct with “human” devotion and love. But the male bluebird, I had read, if he lost his mate, was known to “sing forlornly all day long.” Papa was always there, feeding Mama as she brooded their nestlings in the box, preening her when she left, perching beside him in the cedar tree.

I kept vigil to prevent bully birds such as starlings from invading the box, waving my arms and shouting “Get away!” In a heat wave, I erected an umbrella to shade the box (which can be 20 degrees hotter inside) and sprayed it with a fine mist, which the parents happily flew through. When a red-tailed hawk circled above, I horrified myself by contemplating shooting the raptor, which preys on songbirds, with my air rifle, which I only ever use for target practice, after nesting season.

“It’s the bluebirds’ beauty,” a friend consoled me, upon hearing my confession, “that sucks the brains right out of you.”

Thoreau wrote that the bluebird “carries the sky on his back.” Native Americans held the bluebird sacred for the royal blue feathers adorning its head and back (the female, characteristically more modest, is grayer, with elegant blue tinges in her wings and tail).

For us, especially in the Northeast, the sight of the bluebird—its azure blue plumage brilliant against the pale March sky, its breast the color of red clay, its belly as white as a cloud—is a talisman against winter’s perseverance, an assurance it will end, that color and song will soon return to the bleak, still landscape.

Perhaps, being human, we also prize the bluebird for its relative scarcity. By the 1960s, the Eastern bluebird’s numbers were drastically diminished due to “human interferences” such as pesticides and habitat loss, especially dead trees, increasingly rare on tenanted land, which provide holes for “cavity nesters” such as bluebirds.

But thanks to human interference—specifically, “bluebird trails” (a series of nesting boxes, often in a line or circle), erected by succeeding generations of dedicated individuals, from boy scouts to backyard birders to farmers—the bluebird population significantly rebounded. In 1999, in a stunning, rare and welcome reversal, the Eastern bluebird was removed from New York State’s Endangered, Threatened, and Special Concern list.

The Eastern bluebird was saved, at least in part, because of the “bias of beauty”—a bias, that, despite the saying that “beauty’s only skin deep,” may be ingrained in some species, perhaps even ours.

In birds, it is generally agreed that “sexual dichromatism” (when males and females are colored differently) evolved because of the female’s preference for a brightly colored mate. Studies have shown that the brighter the male’s plumage, the more females will flock to him. (Even seemingly monochromatic species, such as starlings, have ultraviolet colors—invisible to us—whose brightness females use to size up a suitor.)

But the female’s predilection for pretty colors is about more than aesthetics. The vividness of a male’s coloration is an indication of his health and vigor, according to some studies. The female, eager to ensure the survival of her own offspring, also takes into account the condition of his feathers—good grooming, it seems, counts in many species.

In spring, the males of many migratory birds, such as robins and hummingbirds, precede the females to establish territories, which the females, upon their arrival, evaluate, along with the males’ singing voices, choosing a mate for his property and sex appeal (the everlasting appeal of the crooner!), just as humans often do.

Color accents can also catch the eye and make a statement. The male ruby-throated hummingbird, his feathers an iridescent green, also sports a bright red cravat worthy of a dandy, alluring to females but a warning to other males.

Red, it seems, is the universal power color. Think politicians’ red ties, especially at presidential debates, worn to project strength. The red-winged blackbird, resplendent in dress black, flashes scarlet epaulets worthy of a general to intimidate males and attract females. His “wives” (the red-winged blackbird is “polygynous”) are a dowdy brown color, which is their camouflage in nesting season, and they are an unruly harem. DNA studies reveal that not all the rakish red-wing’s eggs are his own. The enterprising females of this species are always on the lookout for desirable males to sire their young. Our demure, certainly less raucous bluebirds, considered “socially monogamous,” form a pair bond that lasts at least through nesting season. But even these dreamy idealists are known to stray. Promiscuity is simply nature’s strategy for diversifying the gene pool.

We humans, supposedly so evolved, are above the blandishments of beauty and key in on character in our choice of a mate. Hmmm. Perhaps, with experience, we learn to consider character, which endures and is more reliable than the vagaries of attraction, and factor it into the alchemy of what we call love.

There is  such a thing as the beauty of character, and what if we developed a broader definition of the beauty of other critters? Our beloved bluebirds are not just pretty songstress; they are also valuable insectivores—they eat insects. Bats, which are not birds but mammals, and Halloween “cute” but creepy to many, can eat as many as 600 mosquitoes in an hour. As insectivores, they are the farmer’s best friend, devouring pests that threaten crops, and a check on mosquito-borne diseases. But cave bat species, especially in the Northeast, are in precipitous decline, due to a deadly fungus, White Nose Syndrome (WNS), which is largely unknown. The loss of the bats would be an eco-holocaust that would impact the economy, our health, and the environment in general. If we would only consider Little Brown bats and their cousins “beautiful,” perhaps, just perhaps, there would be more of an urgency to save them too.

—For Peter Mayer, who loved bluebirds.