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Birding Column: Banding Birds at Devils Postpile |
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Mathew Tekulsky The Birdman of Bel Air |
| February 3, 2004 |
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Mathew Tekulsky writes a regular column about birding in his backyard and neighborhood in Bel Air, California. You can follow his encounters with the birds of the Santa Monica Mountains here on National Geographic News BirdWatcher every fortnight or so. It was 6:30 a.m. in early August, and I had just driven in to the Devils Postpile National Monument near Mammoth Springs, California. As I walked through the campground to catch the trail to the Postpile (the name given to 60-foot columns of basalt in the area), I saw a telltale sign that told me that birders were around—and not just birders, but professional birders. It was a fold-up table that was covered with bird-banding paraphernalia—bands, calipers, rulers, pliers, clipboards with notes, identification books, a scale—the usual assortment of gadgets that field biologists use to capture, measure, weigh, and otherwise study birds before releasing them back into the wild. I had stumbled upon the eastern crew of PRBO Conservation Science, and for the next five hours, I watched field biologists River Gates, Gernot Huber, and Leah Culp (along with volunteer Margina Rhyne) capture and band more than 100 birds, including the orange-crowned warbler; Wilson's warbler; MacGillivray's warbler; yellow warbler; Steller's jay; song sparrow; Oregon junco; lazuli bunting; calliope hummingbird; pine grosbeak; and the irrepressible red-breasted sapsucker. Each bird was captured in one of the ten nets that the biologists had placed among the willows on the edge of the meadows and along the river's edge. The nets were made of 30-millimeter (1.2-inch) green mesh and were about 30 feet (nine meters) long and seven feet (two meters) high. The birds would fly into the netting and then drop into a pocket that was built into each side of the net. The nets were operated for five hours, starting fifteen minutes after sunrise, and they were checked every half hour for new captures. The crew conducted studies at this site every ten days, from May 1 through August 15. This methodology is identical to those of other field biologists in other locations, so that everyone's results are consistent and easily comparable. The aggregate results are designed to give a clear and accurate picture of bird populations throughout the territories that are studied. The first bird that I saw banded was a calliope hummingbird. It was given the number Y89802, but since hummingbird bands are so small, the Y equals the number 4000. Each bird, therefore, has a nine-digit number on its band—room for endless combinations. Needless to say, this was a priceless opportunity to observe tiny birds such as the warblers up close. But by far the most fascinating character of this group was the red-breasted sapsucker. Now, this fellow flies into the net, and as soon as he becomes entangled, he stays perfectly still and quiet, so as not to attract predators. He also remains silent while he is transported back to the table in a small cloth bag, and he remains quiet while he hangs in the bag after it is attached to a clothespin under the side of the table, as each bird waits his turn to be studied. But as soon as he is taken out of the bag, he starts squawking, flapping his wings wildly, and flailing his feet in an attempt to get free from his handlers. Meanwhile, his leg is banded; his beak and feathers are measured; the scientists blow on his belly to expose his bare abdomen and see if any fat has been deposited there; and he is weighed. This is accomplished by placing him upside down in an empty can of fruit juice concentrate that is open on one side. The bird's rump sticks out of the top of the can, but since he's scrunched in there so tightly, he can't move, and since he can't see in the dark, he remains quiet. But as soon as he's pulled out of that can, there go the wings again, there goes the squawking (or rather, screeching!), and there go the claws, digging into the fingers of our intrepid scientists. Indeed, it takes about one to three minutes of prying in order to extricate the tight grip of these claws from a person's hand. But finally, the bird is free, and off he flies into the clear blue yonder. All in a day's work. Tail Piece: Why Birds Are Banded The eastern crew of PRBO Conservation Science is part of a national banding program called MAPS (Monitoring Avian Productivity and Survivorship). Founded in 1965 as Point Reyes Bird Observatory, California, PRBO is a conservation science organization that studies birds to protect and enhance biodiversity in marine, terrestrial, and wetland systems in western North America. The MAPS network includes over 500 stations located in nine regions throughout North America. It is a major research program of the Institute for Bird Populations (IBP), a California nonprofit corporation dedicated to fostering a global approach to research and the dissemination of information on changes in the abundance, distribution, and ecology of bird populations. According to River Gates of PRBO Conservation Science's Eastern Sierra Project, "We use birds as indicators of ecosystem health. In our monitoring projects, for example Devils Postpile, we set up long-term monitoring sites and study the population dynamics as the area is restored, using birds as indicators of the recovering mountain meadow habitat. "By capturing and banding birds, we are able to study the productivity (how many birds are produced in the area) by comparing the adult captures to the capture of young. A ratio is calculated and if the population is stable or increasing, the ratio would be positive or greater than one. "Another benefit of banding is another measure called survivorship, which is a measure of overwinter survival. Because most birds migrate either to southern latitudes or down in elevation, their return to Devil's Postpile each summer to breed is a good indicator of the habitat quality. "We submit our data to MAPS, and they conduct a large-scale analysis of the banding data. This effort is also long-term and is responsible for documenting the decline of songbirds in North America. This is an example of how our site-specific information can be added to international efforts to monitor and conserve bird populations." Previous columns by The Birdman of Bel Air: New Bird-Watching Column: "The Birdman of Bel Air" The California Towhee, Boldly Bland At Home With Hooded Orioles Scrub Jays Go Nuts for Peanuts Northern Mockingbird is a Wary Neighbor Christmas With the Pelicans California-Quail Close Encounter Yosemite Steller's Jay Encounter National Geographic BirdWatcher Regularly updated news stories, features, and columns about birds and birding: Go >> Recent News Stories About Birds Has Mysterious Killer of India's Vultures Been Found? Mystery Bird Discovered On Indonesian Island Deciphering Cowbirds' Complex Song and Dance Buzzards Bounce Back in U.K., Sparking Cull Debate Need Sleep? Birds May Have Shortcut to Second Wind |
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