Biologist Bob Frey cradles a purple finch in his cupped hand and blows gently. Tiny tufts of down float away on the breeze kicked up by Bear Creek, flowing behind him. He lowers the bird into a plastic film canister to measure its weight on a sensitive scale.
It weighs 22.5 grams, about the same as a business envelope filled with two sheets of paper. The loose feathers help Frey determine how many new feathers are being grown, as well as the general level of body fat. He slides the bird out of the canister. It immediately starts pecking at his finger.
When a bird is banded, its age, gender and weight are recorded. When birds are captured and recaptured, scientists gain valuable information that helps answer questions such as: Do they produce young? Do they survive the year? Do they recruit birds into the local population from other areas?
When combined with data gathered at other bird-banding stations — some more than a thousand miles away — banding helps answer questions about migration routes.
The banding stations operated by Klamath Bird Observatory have helped to confirm national trends.
"We've found that the western tanager populations are increasing," says John Alexander, KBO's executive director. "The purple finch is decreasing rapidly here. In Oregon, this decline is associated with habitats we've managed, especially when we've disrupted natural fire cycles."
As Alexander sees it, bird banding helps answer global-scale questions about ecology.
"At KBO, we use birds as our lens to understand ecosystems and natural resources," says Alexander. "And we use the health of bird populations to understand the health of our ecosystems."
"The telltale sign of a purple finch is that it tries to bite you," says Frey. "The very similar-looking house finch that we also have in this area does not bite."
Frey manages the bird-banding program for the Klamath Bird Observatory — KBO. On this chilly April morning, Frey and fellow biologists David Hodkinson and Frank Lospalluto are capturing, banding and releasing birds at a monitoring station in a streamside forest below the Willow Wind Community Learning Center in Ashland.
A gray, plastic helmet with wrap-around magnifying goggles sits on Frey's head, making him look like a cross between an arc welder and a surgeon. He reads the miniscule number on a metal band on the finch's leg.
"It's an aluminum alloy with a unique number on it," says Frey. "No other bird in North America has this number on it, so we can recognize this individual."
A group of 13 fifth-graders from nearby Bellview Elementary School sit on a tarp and watch the banding operation with rapt attention. They're attending a Songbirds, Science and Schools program. Students from Helman Elementary, Ashland High School, Walker Elementary and Willow Wind will learn from the KBO bird-banders over the next four weeks.
KBO Education Project Leader Liz Williams meanders around the group of Bellview students, holding a common yellow throat upright on the back of her hand. She clasps its legs between her middle and ring fingers to prevent it from flying away.
"Who knows what species this is?" she asks.
In a flurry of excitement, students shout "Lincoln sparrow," "American goldfinch," and "ruby crowned kinglet," all species they've seen this morning.
"Look at the bill," Williams says to the fifth graders. She traces an exaggerated arc with the finger of her other hand next to the bird's beak. "This is a larger bill. The common yellow throat eats small insects. It acts more like a pair of tweezers than larger beaks, which are for cracking seeds."
With this image, several of the kids remember the next common yellow throat they see. They also see the larger redwing blackbirds, and the fox sparrow, a distinguishing feature, they learn, is a narrow white ring around its eye.
These may be the details the children will remember for many years.
"I like kids to be enthusiastic about any science," says teacher Max Schmeling. "On other field trips you may point to a bird 50 yards away. This is a local, rare opportunity for the kids to see wildlife up close."
How does Schmeling gauge the effectiveness of this field trip?
"I can see they're learning because they're quiet," he says.
When asked, the students are quick to reveal what they've learned.
"I liked the redwing blackbird," says Nikki Parker. "The female is more brownish and the male is more black."
"I didn't know finches were so common in this area, like sparrows," says Sam South.
The next bird to be banded is a black-capped chickadee. It reminds Alexander of the unexpected connections the banding data can provide.
"We caught one of these at our Medford station at the Jefferson Nature Center on Bear Creek two years after banding it here at Willow Wind," Alexander explains. "It shows the importance for birds of an intact greenway in an urban setting."
Overall, says Alexander, "We've seen about 70 species over the years here at our Willow Wind operation."
He turns to the students and asks them to state a hypothesis about the chickadee's beak, one that can be tested, perhaps with binoculars, by studying its eating habits. In a classroom visit by KBO staff before the banding station excursion, the students learn about hypothesis testing and its importance in scientific discovery.
Through years of hypothesis testing, scientists now believe that salmon are able to relocate their natal streams through an acute sense of smell. Ornithologists have not yet discovered how birds can fly thousands of miles and rest or nest at the same spot year after year.
"There are theories, but no one knows for sure," says Alexander. "Some scientists think birds can sense magnetic fields, some think they navigate by the stars — most songbirds migrate at night."
One of these wide-eyed fifth graders could be the scientist who develops the right hypothesis.
Daniel Newberry is a freelance writer living in the Applegate Valley. Reach him at firstname.lastname@example.org.