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This note from Kim Potter includes two interesting documents in PDF format. Thank you, Kim!
Ken, Here is some more information on our Colorado Rosy-Finch color banding project. The New Mexico population seemed to be small enough to get a good recapture rate. We tried for a high recapture rate but after banding over 1430 Brown-capped Rosy-Finches we still had a very low recapture rate-too low to measure statistically. So we've changed our approach to one red band to signify a Snowmass, Colorado banding site and have set our sights on distribution feed back from birders far and wide. We also have moved to an education focus and look at climate changes in the alpine. Here's a summary of our work FYI and a post that explains to the public our focus. (LINKS BELOW) Thanks for sharing Colorado information and Rosy-finch information with me. Kim M. Potter Wildlife Technician White River National Forest (970) 625-6860 kmpotter@fs.fed.us Overview http://www.rosyfinch.com/WhiteRiverNationalForestRosyJan2011.pdf Color Banding Report 2010 http://www.rosyfinch.com/ColoradoRosy-finchBandingReport2010.pdf
Ken Schneider
Web site: http://www.rosyfinch.com Blog: http://rosy-finch.blogspot.com Photos: http://www.flickr.com/photos/rosyfinch/ |
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From the Snowmass (Colorado) Sun
http://www.snowmasssun.com/ARTICLE/20110302/FRONTPAGE/110309992/-1/RSS A finch in the hand is worth two in the bush. | - Ann Larson/Snowmass Sun Alien abductions of a feathery kind March, 2 2011 By Ann Larson The conifers overlooking the Wine Cabin off of Sam's Knob are alive with birds. They use the branches of subalpine fir and Engelmann spruce as observation decks before swooping down on the wooden bird feeder by the cabin. It's Wednesday and in between the trees and the seed-filled feeder is a fine net, almost invisible to the eye. Sitting at a table outside of the cabin are three wildlife technicians of the White River National Forest Ranger District, Kim Potter, Liz Roberts and Jan Burke. They are there to ensnare birds, and in particular, they hope to catch rosy-finches and especially the brown-capped rosy-finch. The sun is shining on this cold, windy day, so they know conditions aren't optimal for snaring their feathered friends. Enough natural food is available in the mountains. But on a snowy, stormy day, the project leader, Potter, caught 100 birds as they used the feeder for their main source of sustenance. The Brown-Capped Rosy-Finch Banding Project hopes to gain more knowledge of these small songbirds that live almost exclusively in Colorado above tree line. Potter will measure, record and band any bird that gets caught in the 30-foot span of netting supported by thin vertical poles. The first two victims land silently in the nets and hang there without struggling as the three rangers head out on a rescue mission. For the birds, the rescue must seem like an alien abduction. First, they are gently untangled from the net and then put into colorful, drawstring fabric bags to keep them calm. Back at the table the equipment used for banding is laid out, ready for the task at hand. “We are targeting brown-capped rosy-finches (BCRFs) since these birds are almost endemic to Colorado, its breeding range barely sneaking into Wyoming and New Mexico. Most aspects of its behavior, ecology, breeding habits and movements are poorly known,” said Potter. Last ski season, she and her volunteers at the Wine Cabin caught 267 BCRFs of which 13 were already banded; the year before, the total was 427 with 13 banded. “Our aims are to determine an approximation of population size and to obtain data on the movements of the species within its entire range. This is a species we know so little about since the inaccessibility of much of their habitat poses a unique challenge. This monitoring project is the best idea we have for learning something about them,” she said. Federal regulation for the Forest Service mandates that indicator species, such as the BCRF, must be monitored. There are three different species of rosy-finches and all three have been caught and banded near the Wine Cabin since the Snowmass project started in the winter of 2008-2009. The gray-crowned and the black rosy-finches also make it into the nets, but not as often. Only five black rosy-finches have been caught in the last two seasons, while 105 gray-crowned rosy-finches were caught the first year, followed by 10 last winter. Both of them have a much larger range than the BCRFs. As Potter pulls the first bird out of its bag, she discovers that this is the gray-crowned rosy-finch. By her side, local botanist and volunteer Janis Huggins prepares to record all the information about this tiny beauty. Through careful inspection and measurements, Potter concludes that this is an adult male with a wing length of 111 mm and a tail length of 70 mm. Blowing on the bird's furcula hollow above the breastbone, she checks the color under the tiny feathers. If the color is pink to red it means that the bird has a good fat supply, which this one does. Then, because it is windy that day, the bird is brought in to the cabin to be weighed by putting its beak down into a piece of PVC pipe on a scale. This captive weighs in at 26 grams. Metal bands are then secured to the legs using a complicated system of banding to indicate whether it was a first year bird or an adult and in which county it was banded. This little fellow was banded as No. 947 on one leg, with a pink band to indicate Pitkin County on the other. After what must be somewhat of an ordeal for this rosy-finch with the gray crown, Potter carries it into the open and he flies away. No harm, no foul, for this fowl. In the second bag is another GCRF. Another adult male that is bigger than the first one. The two birds seem to be healthy specimens. A chickadee gets caught in the net, but manages to fly away from its captors. Then a pine grosbeak flies into the unseen net and the procedure repeats itself with Roberts making the measurements. While Potter works mostly with monitoring birds including Virginia's warbler and Brewer's sparrow, Roberts' indicator species are mammals such as elk, cave bats, Canada lynx and snowshoe hare. “Working with species in the alpine ecosystem is an excellent place to note climate change. We're also concerned about the effects of dust and dust storms on snow and the pollution from cars that make the snow melt faster. This tricks the alpine birds into laying their eggs too early,” said Potter. A silviculture specialist, whose field of interest is the health of the forest trees, Jan Burke worries about the effect of early snowmelt caused by pollution on trees, whose roots are still in frozen soil. “They are leafing out too early. Managing the forest is more than just two by fours. We are also keeping our eye on the pine beetles in Pitkin County, but it's not such a big problem here because we don't have such a large population of lodge pole pines,” she said. Visitors are welcome at the banding project and local birder and Villager Allen Levantin drops by for a visit. He can often be found there are Wednesdays helping out. “I get to carry the bags. I go up to kibbutz and to help if I can. I think this project is great. It's a real scientific endeavor,” he said. Levantin is one of the three friends whose birding competition resulted in the book “The Big Year: A Tale of Man, Nature, and Fowl Obsession” by Mark Obmascik, which will be released as a movie in November. Levantin considers the Roaring Fork Valley one of the best birding areas in the U.S. More than 250 species can be found here in a good year and Snowmass Village is one of the best places in the country to see all three species of rosy-finches. Another frequent visitor is birder Dick Filby, who takes skiers all over the mountain to see other species of fowl when he is in town. But seasoned birders are not the only ones who head over to the Wine Cabin to check out the flocks of rosy-finches along with pine grosbeak, gray jays, Stellar's jays, Clark's nutcrackers, chickadees and red-breasted nuthatches. Ski instructors bring their classes there to look for birds and on Wednesdays to observe the catch and release of these avian creatures. Those who want to see a wide assortment of the feathered ones can also check three other bird feeders on the Snowmass ski area. Close to the Wine Cabin, there is one by the Sam's Knob Ski Patrol shack, which is closed on Wednesdays to send more birds to the monitoring station. Over at Elk Camp, there is one at the top of the Magic Carpet at Elk Camp Meadows and another near the top of the Elk Camp lift by the ACES cabin. Project partners for the rosy-finch project include the Aspen Skiing Co., the Town of Snowmass Village, Roaring Fork Audubon and other bird-related organizations. Visitors are welcome to come by the Wine Cabin each Wednesday, except March 23, to watch the banding project. Copyright 2011 Snowmass Village Sun. All rights reserved. This material may not be published, broadcast, rewritten or redistributed. Snowmass Village Sun March, 2 2011 10:37 am http://www.snowmasssun.com/apps/pbcs.dll/article?AID=/20110302/FRONTPAGE/110309992/1039/RSS&template=printart
Ken Schneider
Web site: http://www.rosyfinch.com Blog: http://rosy-finch.blogspot.com Photos: http://www.flickr.com/photos/rosyfinch/ |
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