Invasion 2000: Canada's Finches At U.S. Feeders

"The citizen-scientists who participate in Project FeederWatch and other bird-watching surveys may be in for a real treat this year," says Laura Kammermeier, FeederWatch project leader at the Cornell Laboratory of Ornithology. "If patterns of the past decade hold true, then winter bird-feeding enthusiasts through much of the central and eastern U.S. should expect a big showing of northern finches this winter."

North America's winter finches include pine grosbeaks, purple finches, red crossbills, white-winged crossbills, common redpolls, hoary redpolls, pine siskins and evening grosbeaks. "Irruptions" are large-scale movements of birds from one area to another.

Ornithologists base their predictions on more than 10 years of data collected by thousands of diligent backyard bird-watchers throughout the United States and Canada. Observations by FeederWatchers have revealed a two-year cycle in the southward movement of some northern finches. Evidence suggests that these southward wintering forays may be related to food shortages farther north.

This winter the professional ornithologists expect the network of volunteer bird-watchers to lend more insight into the invasion phenomenon. To that end, the Cornell Laboratory of Ornithology in partnership with the National Audubon Society will sponsor several additional surveys to monitor bird populations:

-- The Irruptive Bird Survey will collect information about finches and other irruptive winter bird species. A similar project, the North American Winter Finch and Red-breasted Nuthatch Survey, was developed during the fall of 1997 and proved instrumental in mapping a massive invasion of winter finches that winter.

-- Participants in the annual Christmas Bird Count, now in its 100th year, will look for birds at some 1,700 locations across North America.

-- The Great Backyard Bird Count 2000, scheduled for Feb. 18-21, works much like FeederWatch except that participants make the survey in their backyards and other locations during four winter days only.

"Our citizen-scientists live across the entire continent, and without their work we would never be able to study changing winter distributions of the birds in North America," says Wesley Hochachka, research associate in the Cornell Laboratory of Ornithology. As examples of these changes, he cites the following observations of large flocks of American robins in northern states last January, the apparently gradual conquest of the West by blue jays and last winter's western irruption of pine siskins:

-- Data from FeederWatchers show a general increase in overwintering robins in the central and northern parts of the United States last winter In Miles City, Mont., bird-watcher Patricia Gudmundson reported, "In January, my whole town was full of flocks of robins. While I've seen them here in winter before, I've never seen so many, nor seen them stay so long."

-- Once, when FeederWatchers in the West reported "blue jays" at their feeders, they actually were seeing Steller's jays (Cyanocitta stelleri), not true blue jays (Cyanocitta cristata) that are common to eastern North America. However, FeederWatchers in many parts of the mountainous West are reporting the eastern blue jay in their yards, sometimes for many years in succession. Ornithologists believe that these western-most blue jays are probably part of a gradual westward spread of the breeding range of this species. FeederWatchers are helping to document this expansion.

-- Pine siskin irruptions (from the coniferous forests of Canada) are periodically noted by FeederWatchers in the East, but last year was the West's turn. "I sometimes saw as many as 100 pine siskins at my feeders," reported Marvin Ellison of Vancouver, Wash., while Karen Buckallew of Evanston, Wyo., observed "large flocks -- between 75 and 100 birds," and FeederWatchers in Alaska and Washington state counted flocks of 327 and 240, respectively, of the little brown finches with the in distinctively striped breasts.

1999 Top 10 Feeder Birds of North America

Source: Project FeederWatch, Cornell Laboratory of Ornithology

1) Dark-eyed junco

2) Mourning dove

3) House finch

4) Downy woodpecker

5) American goldfinch

6) Blue jay

7) Northern cardinal

8) Black-capped chickadee

9) White-breasted nuthatch

10) European starling

NOTE: Regional lists available at http://birdsource.cornell.edu/pfw/pfwnews.htm

Related World Wide Web sites: The following sites provide additional information on this news release. Some might not be part of the Cornell University community, and Cornell has no control over their content or availability.

-- Cornell Laboratory of Ornithology: http://birds.cornell.edu

-- National Audubon Society: http://www.audubon.org/

Information on Project FeederWatch, the Irruptive Bird Survey, Christmas Bird Count and the Great Backyard Bird Count 2000 is available online at http://birdsource.org. Volunteer citizen-scientists may join Project FeederWatch by calling the Cornell Laboratory of Ornithology toll free at 1-800-843-2473. A nominal fee is charged for participation in Project FeederWatch and the Christmas Bird Count.