Observing birds in their natural setting is one of my favorite pastimes. Because most will not tolerate being approached, binoculars are generally indispensable. Seeing wild birds from up close is a rare privilege, and banding stations (or ringing stations, for British English speakers) offer such views. One I am familiar with and have visited repeatedly is located not too far from Colorado Springs at Chico Basin Ranch, in the eastern reaches of El Paso County.
In addition to being an environmentally-conscious, conservation-oriented, active cattle ranch, Chico Basin is the number one birding hotspot in El Paso County (and number two in neighboring Pueblo County to the south, as it straddles the county line). Its terrain lies along an area where two migratory routes in North America—the Central and Pacific Flyways—overlap. The presence of water and trees in the middle of the plains is an invitation for birds to take a rest, which makes it an ideal site for a banding station.
Each spring and fall, the Bird Conservancy of the Rockies, under the auspices of the US Department of the Interior, organizes a month-long banding period staffed by master banders. So-called mist nets are erected in densely vegetated areas with high avian activity. Birds don’t see the nets and are caught in their fine mesh, from which they are carefully extracted. To keep them calm and protected until their evaluation, each individual is enclosed in a hand-sewn, seamless cotton bag corresponding to its size, and hung on a rack.
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When it’s a particular bird’s turn, it is pored over painstakingly. Its species is identified, fat stores assessed, wingspan and tail length measured. Age is determined with the help of additional parameters, such as state of plumage, stage of molt, and degree of skull ossification; gender (in the absence of sexual dimorphism) by evaluating the sexual organs, which swell during the breeding season. When a captive’s identity is still uncertain, more arcane measurements are in order.
Banding stations are repositories of the tools of the trade, and of relevant ornithological literature. A copy of the “Bible” of banders, Peter Pyle’s Identification Guide to North American Birds is mandatory. Its two volumes illustrate and enumerate pertinent details that help banders determine what species they are holding. Nobody knows everything, but every bander knows where to look up information. And fast, to limit the amount of time a bird is handled, and the attendant stress.
A light, numbered aluminum band that does not interfere with the bird’s activities is selected and fastened to one leg, based on that extremity’s thickness. Experienced banders know which diameter to choose for each bird, but a nifty gauge can assist in the selection. In case a bird is recaptured (which happens infrequently), the band’s unique serial number allows tracking that individual’s movements as well as longevity and might offer intriguing information. In 2017, the Cornell Lab of Ornithology published an online article about a Yellow Warbler being banded in northern Colombia before it was re-captured in New York State 2 months later and 2,300 miles away—a small sensation.
The final step consists of establishing the bird’s weight by placing it head first in a tube wide enough to encircle it, but narrow enough to limit movement in order to prevent injuries. When it is finally released, it typically takes off from the bander’s flattened hand. Some do so immediately, others need a moment to get reoriented to their surroundings.
The birds’ differing reactions to their capture are equally as fascinating as the itinerary they follow during their twice-annual migration. Some individuals seem silent and subdued, others anxious and agitated. A few appear utterly indignant at their confinement and loudly express their displeasure at being handled. And yet others look to be completely unfazed by the goings-on and get to pose for a moment for the admiring observers before returning to their pre-capture pursuits.
Banders in action remind me of dancers in an artfully choreographed performance. Birds, the beguiling ballerinas, are gently but assuredly lifted, repeatedly rotated, and finally released. As I watch these winged wonders vanish into the foliage of nearby trees after their brief ordeal, I wish them smooth sailing. May they gain enough weight during their layover to carry them securely to their breeding or wintering grounds and bless us with their presence again come next spring or autumn.
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