Photographs by Rory McNamara
Flight Risk: Kyle Wright extricates an American goldfinch from the net.
The Pt. Reyes Bird Observatory monitors the life of the skies
By Gretchen Giles
There was a time, not so very long ago, when the dominance of the dinosaurs was on the wane and the earth itself was up for grabs. The largest mammal then living was the size of a spaniel, but the biggest flying animal was, in the words of naturalist Sir David Attenborough, "immense."
In his award-winning 1998 documentary The Life of Birds, Attenborough calls this creature the "Terror Bird," and an animated sequence shows the thing materializing around him from the discovery of one enormous thigh bone. Massive and flightless, with huge jaw bones equipped with sharp, crushing teeth, the Terror Bird was nature's prehistoric experiment with the oversized avian, the ostrich being a pale and distant undersized cousin of such majestic ancestry.
The Terror Bird had no reason to fly, but as mammals grew in population, species, and cunning, its fellows developed the necessity. Flight is born from the need to escape, and birds gradually lost their teeth and heavy jaws, their bones lightened, and what had been the keratinized scales of those granddaddies the reptiles became the keratinized feathers of an entirely new genus. They ceded the ground to the mammals and took to the air.
But in the firmament they have populated, birds rule an entire universe of mystery and passion parallel to that of the land. What's more, their lives may be the best indicators we thick, heavy, and gravity-bound mortals have of our own chances for survival.
For the Birds
The springtime mating cycle finds birds at their most vulnerable and most visible. The skies seem to be full of small, angry Brewer's blackbirds ferociously chasing large, hungry red-tailed hawks away from their nesting territories--and winning. The trees ring with outraged squawks when a predator is successful and a chick is snatched from the nest.
Yet such obvious specimens as hawks and blackbirds don't begin to explain the phenomenon of bird watching--known to the initiated as "birding" and to the contemptuous as "listing"--in the United States. According to the Environmental Protection Agency's latest report, some 63 million Americans spend $20 billion each year on this fast-growing hobby, their numbers increasing by as much as 30 percent annually as newcomers get increasingly hooked on scanning the skies. As many as 25 million people travel each year specifically to watch birds, and in 1991--the most recent year for which data is available--this movement generated 191,000 jobs and $895 million in tax and revenue nationally.
These numbers are encouraging to the field biologists working at the Pt. Reyes Bird Observatory's Palomarin Field Station above Bolinas. Established in 1965, the PRBO is the oldest bird-data-collecting institution in the United States, with outposts on the Farallon Islands, Washington, Oregon, Nevada, Idaho, and Latin America.
With a $5 million annual budget, a full-time staff of 65, and 100 paid seasonal interns, it is also among the largest. Following a mandate to study and conserve birds' ecosystems throughout the western United States, not only to protect the animals themselves but to learn how to better protect our own species, the PRBO makes important recommendations to the Bureau of Land Management, the USDA Forest Service, and the U.S. Geological Survey.
Some 4,000 visitors a year, most of them schoolchildren, come out to watch the collection of this information, discovering that such high-level scientific investigation usually involves a gingham cloth bag sewn up by someone's wife and an old Bonnie Hubbard orange juice can.
Wings of Desire: An intern bands an American goldfinch.
Three days a week at dawn, the interns and staff of the Palomarin Field Station haul up the ropes on seven sets of misting nets. Strung and pocketed with a tough yet ultrafine mesh nylon, these nets seem to disappear in the morning's damp light, making them invisible to the birds swooping among this outpost's coastal scrub. Once the nets are secured in place, the staff execute a dedicated sweep of them every 30 minutes, or every 15 minutes if it's raining or stormy.
Their intention is to briefly capture a bird, band its leg or note its code if already banded, and to enter the particulars of age, sex, and weight into their records. Once this swift notation is completed, the bird is carried outside where it gratefully flaps quickly away.
On a brilliant April morning, intern Kyle Wright, a 20-year-old student at Virginia Technical University who has taken a semester's leave from academic work for some hands-on study at PRBO, is gently untangling a chestnut-backed chickadee from a net. Interns must have three weeks of training before they're even allowed to touch the nets, and Wright has never had the challenge of a chickadee before.
A sweet-faced youth with untied shoelaces, he works patiently to free the animal, a task not aided by the chickadee's uncanny ability to swiftly re-entangle itself. After five long minutes of gentle concentration, Wright is successful and the bird is quickly cupped into an inside-out cloth bag with a thick white cord that he soon turns right side out, pulling the cord tight. The chirps immediately stop and the bird is calmed.
Farther along the net trail, PRBO education director Melissa Pitkin and intern Caroline Pakeltis, a postgraduate student from Ohio, have freed and bagged a golden-crowned sparrow. At yet another net, a California towhee complains and is taken. It's been a good run and they are eager to catalogue their findings.
Back at the airy visitor's center, with its interpretive exhibits in the back and large windows up front, hummingbirds gather outside to dip constantly at the feeder, and intern Jennifer Lousk awaits her colleagues' return. Wright, Pitkin, and Pakeltis hang their bags by their cords on a pegboard, the occasional cloth-bound bump the only clue that wild creatures rest within. Gingerly loosening a bag and retrieving its contents, Wright holds his chickadee on the counter in what he terms a "bander's grip," somewhat akin to a Vulcan grip except that his intention is to secure the bird, not make it faint.
"Basically, we're putting little aluminum bands on birds' legs with a number on them so that we can keep track of individuals and also look at long-term population," he explains as he works a small piece of metal. "This way we can keep track of birds migrating out of the country and possibly keep track of where they're migrating to and see if they're recaptured in other areas."
Pitkin--who assures that the capture methods employed at the PRBO have "less than a 1 percent mortality rate, including those birds that we find already dead"--adds that the bands "fit more like a bracelet than a watch. They can move around but they're not going to fall off or get caught."
Of particular interest to the staff are those flyers that travel south each year. "[Scientists] are getting a bit more standardized down in Central America," Pitkin says as she frowns in concentration over her sparrow, "and that's what a lot of our work down in our Latin America program is focused on: training and engaging biologists there in the standardized methods so that they can be doing these types of monitoring programs that can be shared between countries, because we share the birds."
When asked why that is important, Pitkin replies, "Birds are excellent indicators of ecosystem health. They're a top-level predator; they feed on insects. They're very sensitive to changes in environment and habitat quality, and that can range from land to ocean habitats. We have a whole program that just studies marine ecosystems. We study fish that are being eaten which is linked to ocean temperature, which can be linked to climate change and global warming, and we then relate that to fisheries.
"The same can be said of birds that occupy man's habitats," she continues. "If we notice that our data for a specific site is showing a decline of species, it begs the question why. We might notice then that some sort of human alteration is happening to the habitat. Maybe there's been development, deforestation, grazing or who knows what--it depends on the site. We try to evaluate the response that we're finding in our data of bird populations to whatever land use is going on there."
Man and Nature: Kyle Wright observes an American goldfinch.
Lure of the Bird
The rift between recreational birding and scientific study is wide. Wright admits, "I'm coming from a different side from a lot of the people here in that I was originally a birder and now I'm getting into the biology of it," Wright admits. "I know that a lot of people joke that I'm a 'lister.'"
"Someone who goes to different places to see different birds"--and then lists their accomplishments, he explains.
The listers have a little respectability problem. Pitkin quickly jumps in. "While some people here might tease Kyle, probably every person here has a list of what they've seen and what they haven't seen," she says. "Even I do. It may not be a list written down on paper, but I certainly know when I've seen a new bird.
" 'Listers' is a term for people who are getting into it like a hobby or a game. Some people have a list of birds that they've seen per county. I think that it's human nature to make a game of things, and," she assures, "I'm all about having people connect with birds, however it is."
Comforting to ordinary birders is the PRBO's similar reliance on identification books, albeit poop-besmirched copies, as the staffers here are lucky enough to be holding the birds they're identifying next to an illustration or description rather than catching brief glimpses of them in the sky.
After birds are banded, which is done first in the event that the bird needs to be immediately released or actually gets away, PRBO staffers seek other information. It's almost pleasing to note that what's in the books doesn't always match up to reality. Lousk works on the towhee, which the guide assures should either be brown or glossy black for female or male, respectively. It's actually a bit of both, so she carries it over to the door's natural light to try to discern. Sometimes even a field biologist just can't be sure.
Meanwhile, Pitkin, who visited the PRBO on a third-grade class trip before becoming an intern and then a staff member, is blowing back the feathers of her sparrow's belly. A bird that is nest-sitting will have a "brood patch" on its stomach where the feathers have dropped off and the stomach veins have thickened to better emit heat to its eggs.
"Oh, man!" she cries. "This one is-- omigod!--female; you can see the egg."
And indeed, the extremely thin skin of the bird's belly does reveal the press of the pure white ovoid shape of a small sparrow egg ready to drop.
"Sorry little thing, oh I'm sorry," she coos as she shifts from conversational mode into the fast-working biologist that she is.
Not wanting to stress the mother, Pitkin decides not to weigh her, as it involves upending the bird into an orange-juice can. Hummingbirds are weighed in film canisters, other birds in the elegance of an empty container of flaky gold-fish food.
Vital statistics measured, Pitkin replaces the sparrow in a bag and walks her all the way back to release her near the net where she was found, in order to better facilitate her quick return to the nest, where other eggs must surely await given the size of her brood patch. At least Pitkin didn't need a book to determine the sex of this one.
As she walks back to the visitor's center, Pitkin is asked if it's hard to leave here after a day's work. Giving a merry laugh and referring to her long association with the place, she grins, "I never have."
Which can only be good news for the emperors of the sky.
The Palomarin Field Station is open to the public Tuesday-Sunday, 15 minutes after dawn to six hours later. Free. For complete details, phone 415.868.0655 or visit www.prbo.org.
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From the June 5-11, 2003 issue of the North Bay Bohemian.