Hilton Jr., B. 1991. Bird-banding basics. WildBird 5(10):56-59.

(Note: The draft below was submitted to WildBird magazine; the article that actually appeared in print may have been edited.)

If you've ever seen a bird with a tiny silver bracelet on its leg, you know someone once had that bird in hand for at least a moment, and if you've actually found a bird with a leg band and reported it to the U.S. Fish & Wildlife Service, you're part of an important network of wild bird research.

Bird banding is one of the most useful tools in ornithology, and its success depends on public willingness to report banding encounters. In North America, birds are captured and marked with numbered aluminum bands by licensed banders who report banding dates and locations to the federal Bird Banding Laboratory. If a bird is recovered or recaptured later at a distant locale, the finder and bander can be linked to exchange information about the bird's age, how far it traveled, and other interesting aspects of its life.

Data from recovered bands provide otherwise unattainable information. For more than 50 years, for example, birders have sat on North Lookout at Hawk Mountain Sanctuary in Pennsylvania to watch majestic raptors glide past in fall migration. Counting those birds tells us something about hawks, but without a banding program at Hawk Mountain we could only speculate about where those birds have been, where they're going, or how long they've lived. Through banding, we broaden our knowledge about distribution and movements of many bird species, their relative numbers, annual production, survivability of offspring, lifespans, and causes of death. Such information helps us manage and conserve birds wisely at a time when they suffer greatly from habitat loss, pesticides, and a variety of unnatural hazards.

People have been banding birds-or "ringing" them, as Europeans would say-for centuries, and birds have been marked in other ways since ancient times. The earliest known marking is from the Second Punic War in about 218 B.C., when Roman footsoldiers captured swallows at headquarters and tied threads around their legs. On each day the soldiers marched, they placed one knot in the string so that when a swallow was released from the front and returned home it would bring a message of how far the troops had traveled.

By the late 16th century, many kinds of birds were being marked. Marco Polo reported that Chinese barons outfitted hunting falcons with silver tablets, each inscribed with the owner's name and province so lost birds could be returned. The first record of a metal band attached to a bird's leg was about 1595, when one of Henry IV's banded Peregrine Falcons got lost in pursuit of a Bustard in France and showed up 24 hours later in Malta, about 1,350 miles away! For that trip, the bird averaged at least 56 miles an hour!

In the 18th century it was common for falconers to attach rings to birds stunned but not killed by hunting hawks. Duke Ferdinand, for example, placed a silver band on a Common Heron in about 1669; the bird was recovered by his grandson about 1728, indicating the heron lived at least 60 years. And in 1710 in Germany, a falconer captured a Great Gray Heron bearing several rings, one of which had been attached in Turkey-more than 1,200 miles to the east.

Christian Mortensen of Denmark began systematic bird banding in Europe in 1899, first on starlings and later with storks, ducks, and birds of prey. He received so many interesting recoveries of banded birds that other Europeans took up the practice. The German Ornithological Society started a banding station in East Prussia in 1903 and French and British scientists began large-scale banding six years later.

John James Audubon is acknowledged as the first American "bird bander." In 1803, while living along Perkiomen Creek near Philadelphia, Audubon wrote this about phoebe nestlings in the mouth of a cave: "When they were about to leave the nest, I fixed a light silver thread to the leg of each, loose enough not to hurt the part, but so fastened that no exertions of theirs could remove it. At the next year's season when the Phoebe returns to Pennsylvania I had the satisfaction to observe those [birds nesting in the Perkiomen] cave and about it. Having caught several of these birds on the nest, I had the pleasure of finding two of them had the little ring on the leg." Audubon's encounters are among the first records of birds migrating from breeding grounds and returning in subsequent seasons.

In 1903, a century after Audubon caught his phoebes, Dr. Paul Bartsch visited colonies of Black-crowned Night-herons near Washington and marked 75 birds with bands inscribed "Return to Smithsonian Institution." One night-heron was found dead in Cuba two years later--the first long-distance record of a bird banded in America--and Bartsch's work was the first scientific use of numbered bands in the Western Hemisphere.

The real pioneer bander in the Americas, however, was Jack Miner, who established a waterfowl sanctuary near Kingsville, Ontario, and tagged his first Mallard there in August 1909; that very duck was shot by Dr. W. Bray at Anderson, South Carolina, four months later. By 1939, the year of his death, Miner banded 20,000 Canada Geese, many of which carried bands returned to him by hunters across the continent. Coincidentally, Miner took credit for helping some goose hunters "get religion," since his bands also carried biblical inscriptions such as "He careth for you, Peter 5:7" and "Be not afraid, only believe, Mark 5:36."

As more people became banders, it was obvious that a centralized system would facilitate storage and exchange of information, so in 1911 the American Bird Banding Association was formed. By 1920, banding was so widespread that it couldn't be coordinated by a private group and the U.S. Biological Survey assumed control. Today, through treaties between the U.S., Canada, and Mexico, migratory songbirds and many other bird species in North America are protected from indiscriminate killing and hunting, and the Canadian Wildlife Service and U.S. Fish & Wildlife Service work closely together through the Bird Banding Laboratory to oversee the activities of dedicated banders.

The federal Bird Banding Lab (BBL) issues a limited number of banding permits to institutions and individuals-mostly professional ornithologists, graduate students, or wildlife biologists. Non-professionals can be certified, but getting a permit is difficult and time-consuming. It's best to start by assisting a licensed master bander for several years before applying for a sub-permit that allows you to band without supervision but requires you to report your data through the master permittee. Only after such an apprenticeship-in which you learn how to safely capture and band birds and deal with detailed but all-important paperwork-should you apply for your own permit.

The BBL provides banders with sequentially-numbered series of bands in more than a dozen sizes. Standard bands are ultralight aluminum that has no significant effect on a bird's ability to fly, feed, or reproduce. Very small bands with less than 1/8th-inch inside diameter are used on birds such as warblers and chickadees, while geese and eagles take large bands an inch across. Each band bears a unique number and a small inscription to "Advise the Bird Banding Lab, Washington DC." As a band is placed on the bird's leg, the bander records the number, the bird's species name, its age and sex, and the place and date of banding. Later the bander sends this information to the BBL, where it is checked for accuracy and made available through a computer database if a banded bird is reported. Banders may collect additional data such as wing, tail, and weight measurments, plumage condition, external parasites, and other information for specific research projects.

According to BBL biologist Danny Bystrak, between 1.1 and 1.2 million new birds are handled each year by American banders. About 70% of these are nongame species (including 4-5% hawks), with the remainder being ducks, geese, and other gamebirds. Of all these, only about 50,000 are reported each year-down significantly from 100,000 annual reports a decade or so ago.

Encounters of banded birds are of two main types: recoveries or recaptures. A recovered bird is one that is found dead, sometimes by a layperson who happens to find the specimen. Often the bird was killed by flying into a window or vehicle, but sometimes the family cat pounces on a banded bird and deposits it on the porch. The vast majority of reported recoveries come from hunters who shoot waterfowl or other gamebirds that were banded on their breeding grounds. Still other banding encounters are the result of live-bird recaptures-usually by another bander-in which the previously-banded bird is released back into the wild.

My own banding station at Hilton Pond, near York in South Carolina's north central Piedmont, is a perfect example of how time-consuming, frustrating, and rewarding the bird banding process can be. During mild weather, I rise at dawn several days each week and walk the trails that meander around my pond and 11-acre nature preserve. Along the way I unfurl a dozen "mist nets" that are seven feet tall by 42 feet long. These devices look like giant hair nets stretched between poles and are essentially invisible against vegetation so that birds fly along and blunder into them, becoming ensnared by the fine mesh. Once each hour until sunset I retrace my steps and carefully remove each bird, placing it in a lingerie bag for the trip back to my banding office. There I record data, band each capture, and release it unharmed. During wet or cold weather when a netted bird would lose its insulation, I rely on automatic and pullstring traps, most of which fit on feeders that lure the birds.

When you look out the window at birds in your yard, it's impossible to know just how many individual robins or cardinals inhabit your property. One thing I was interested in at Hilton Pond was how many birds make use of the area for food, nesting, or shelter, and I've been amazed at what I learned. From 1982-when the Hilton Pond banding operation started-through May 1991, I banded 17,693 birds from 113 species, the vast majority of which were songbirds. More than half were from just four species: Purple Finch (3,068), House Finch (2,550), American Goldfinch (2,054), and Pine Siskin (1,486). My fifth most common bird is the Ruby-throated Hummingbird (787 individuals)-which requires a special authorization from the BBL to capture and band-followed by Northern Cardinal (695), White-throated Sparrow (676), and Yellow-rumped Warbler (661).

Handling so many birds from different species is the time-consuming but rewarding part of banding. The frustrating part is that of all my birds, only 21 have been recovered or recaptured outside my home county, with another 13 reported from nearby sites. That's a rate of 0.19% and is well below the national averages of 5% for all birds and 1% for nongame species. I don't band game birds, but I should still get more birds recovered than I do. My only explanation for such low results is that I band in a largely rural region of the South where there aren't as many people to find banded birds, and there are very few Carolina banders who might recapture one.

Despite the low recovery/recapture rate for birds banded at Hilton Pond, the reports still nicely demonstrate the kinds of information that can be derived through a banding program. For example:

• An immature male Hooded Warbler, banded in August 1987 during migration, was netted the following May on breeding grounds near Chapel Hill, NC, by a graduate student studying this species.
• Two Pine Siskins, banded at York a year apart in the winters of 1987 and 1988, were retrapped an hour apart in May 1988 at Duluth, MN, by Dennis Meyer. (The approximate straight-line air distance between my banding station and Duluth is 990 miles.)
• A White-throated Sparrow, banded on April 15, 1990, was caught and killed by a cat 970 miles away and only 16 days later at Lake à la Ligne, Quebec.
• A Purple Finch, banded in York (not far from the southern edge of its winter range) was found dead 1,660 miles away at Lewisporte, Newfoundland (the very northern limit for this species).

Half my recoveries from York have been Purple Finches (right) or House Finches, probably because they frequent feeders where people are likely to find them. Other species I banded that have been recovered outside York County include Blue Jay, Common Grackle, and Yellow-rumped Warbler. I've also trapped five birds that were banded by someone else, including two House Finches handled by Bill Pepper at Conshohocken, PA. Another bird of interest was a Purple Finch I retrapped at York after it was banded in Maryland by Chan Robbins, author of the Golden field guide, Birds of North America.

Although I've spent thousands of hours netting and trapping at Hilton Pond and had reports on only 34 of my banded birds, the data I've collected on longevity, site fidelity, and species diversity offset my low recovery rate. For example, in the winter of 1989-1990, I recaptured 26 of my previously-banded Purple Finches, including two from 1984 that were at least eight years old. And in May 1991 I netted three migrant Connecticut Warblers at York-not bad since there had been just 12 previous reports of the species for the entire state of South Carolina!

Finally, there's the female Ruby-throated Hummingbird I banded in 1987 as a recent fledgling. This tiny feathered dynamo-four years old in 1991-has been in my traps at least once every year since then. It's amazing to think how many times she's been across the Gulf of Mexico into Central America and still found her way back to my South Carolina backyard each spring! That amazing discovery by itself justifies all the hours I've spent tending nets and running traps as part of the North American bird banding program.