Much about the bird remains a mystery. "The controversy surrounding the existence and causes of a global decline in the sparrow is borne from the scientific uncertainty surrounding almost every facet of the biology of this difficult-to-observe subspecies," wrote a panel of ornithologists appointed three years ago to review the literature on the bird.
One person who does get up-close is David Okines, who has spent the past several springs trying to catch and tag every Cape Sable in Everglades National Park. On a recent weekday morning, Okines rises before dawn and, with Brazilian graduate student Raquel Marques, 26 years old, drives a few miles down the main road from his temporary housing inside the park to an area just east of Mahogany Hammock. "These are very finicky birds," says Okines, a 42-year-old professional birdbander recruited by Pimm through the British Trust for Ornithology. "Last year, fire went through this plot, so it gave us the ideal opportunity to see how they would come back."
Shouldering small backpacks, Okines picks up a tape recorder, Marques grabs a rolled-up mist net, and they walk out into the waist-high grass. The rainy season has not yet started, and the ground is carpeted by dry, flaky periphyton, a spongy plant. The temperature rises with the sun, but there are no mosquitoes. After a few minutes' hike, Okines snaps on the tape recorder, which emits a raspy call that repeats over and over. Suddenly a small, dark bird flies up briefly from the grass and just as quickly disappears.
But both Okines and Marques spot the bird immediately, and Marques is already unfurling the net, a tight mesh of fine thread. When the net is up -- strung between two aluminum poles as if for a volleyball game in hostile terrain -- Okines drops the squawking tape recorder on the ground downwind of the net, and the two researchers move a few yards away.
Minutes later, the bird surfaces again, heading for what sounds like a territorial interloper. And then another bird flies up, weakly, and Okines rushes toward it. "A fledgling," he says, cupping the young sparrow gently in his hand. Now Marques and Okines walk through the grass and drive the other bird toward the net. The sparrow hits the mesh and is entrapped in the cord.
The two birds, which turn out to be a mother and child, offer a jackpot of data. From his backpack, Okines lays out a series of instruments that allows him to weigh the birds; take measurements of their beaks, wings, and overall length; and then, with a dollop of Superglue, affix to their filament-thin legs four bands that assign the sparrows permanent numbers and mark the date they were caught and examined. To aid a study being run by a Brazilian colleague, Marques checks the birds for parasites.
"These sparrows occupy such a fine niche in the world," says Okines, who grew up in Hastings, England, wanting to do exactly this work. "They have to have the right kind of grass, the right water levels to nest, the right size territory. But they are wonderful birds."
Indeed, up-close, the sparrow is no longer dark and nondescript but a colorful sprite of intricate detail. Its olive back is distinctly streaked with varying hues of gray and brown, while the white canvas of its breast is marked by vertical black stripes. Over each eye, the sparrow wears a dash of brilliant yellow, and a patch of yellow shows up again on the edge of the wing. The eyes are brown, and dark whiskers jut from each side of its alabaster throat. Full-grown, a Cape Sable seaside sparrow weighs little more than half an ounce. But in miniature, they are as spectacular as eagles.
Although not gregarious animals, the sparrows aren't bores, according to scientists who have hung out with them. "They are like someone you see at a party just listening to everyone else. They seem shy at first," observes ornithologist Julie Lockwood. "But once you engage them in conversation, they will talk your ear off."
And what do they say? Answers Lockwood: "'Leave me alone.'"