Predicting Winter Finches
The arrival of finches from the north has always been an event that birders here in Maine and New England have looked forward to during the cold of winter. Common redpolls and the much rarer hoary redpolls, pine siskins, evening grosbeaks, pine grosbeaks, and white-winged crossbills are the winter finches that Maine birders probably watch for most eagerly. It is true that pine siskins, evening grosbeaks, and white-winged crossbills breed scarcely but regularly in parts of Maine, and pine grosbeaks have occasionally bred in far northern Maine. But in summer, they tend to be in small numbers in widely scattered locations here in our state. Common redpolls and hoary redpolls breed far to the north of us in northern Canada.
Because of the great interest in winter finches by birders in southern Canada and the U.S., a Canadian naturalist named Ron Pittaway began writing an annual forecast of which species of finches would move south into different areas. He based the forecast on observations of cone and seed crops, and on spruce budworm outbreaks across Canada that he gathered from friends and colleagues. Redpolls and pine siskins have been long known to have a general two-year cycle that causes birds to move southward in some part of the range (especially into the eastern U.S.). Other species are less predictable, and even in redpolls and pine siskins, there is much variability from year to year.
Ron retired from the forecasting a few years ago and asked collaborator Tyler Hoar to take over for him. Tyler is part of a relatively new non-profit called The Finch Research Network, and that is where his annual finch forecasts are published. This year Tyler’s predictions suggest that there may be small numbers of redpolls and pine siskins and, as the winter progresses, more pine grosbeaks. White-winged crossbills are predicted to be low in number and evening grosbeaks possibly in higher numbers than in recent years.
We delved into eBird to see what birders in our region have been seeing by way of these winter finches over the last six weeks. Common redpolls are decidedly scarce with only one bird reported to eBird in the area from Wiscasset. Oddly enough, a single bird was photographed on Bermuda in early December, so apparently there are a few making some big movements—maybe we’ll be seeing more as the season progresses.
Pine siskins, on the other hand, are being seen in good numbers at many widely scattered locations in the Boothbay and Wiscasset areas, with some backyard feeders hosting 40 or more individuals at a time. In line with Tyler’s prediction, there are no reports of white-winged crossbill in the Boothbay-Wiscasset region but there have been a few sightings of groups of red crossbills including at the Bigelow Labs and the Botanical Gardens.
Pine grosbeaks have not been reported yet from Wiscasset or south down the Boothbay peninsula, but birds are appearing in greater numbers a few hours’ drive to the north. We would like to suggest that those of you on the Boothbay peninsula start watching for them. But we have to point out that the only winter record of pine grosbeak in the eBird database from south of Edgecomb was from friend and renowned birder, the late Peter Vickery, in December of 1986! We expect that’s just because many of you local birders have never archived your own sighting records in the eBird database (you can at any time!). If you do see some pine grosbeaks in the coming weeks, we encourage you to add them to eBird (www.ebird.org) so we can all track the movements of these and the other wonderful finches of winter.
Jeffrey V. Wells, Ph.D., is a Fellow of the Cornell Lab of Ornithology and Vice President of Boreal Conservation for National Audubon. Dr. Wells is one of the nation's leading bird experts and conservation biologists and author of the “Birder’s Conservation Handbook.” His grandfather, the late John Chase, was a columnist for the Boothbay Register for many years. Allison Childs Wells, formerly of the Cornell Lab of Ornithology, is a senior director at the Natural Resources Council of Maine, a nonprofit membership organization working statewide to protect the nature of Maine. Both are widely published natural history writers and are the authors of the popular books, “Maine’s Favorite Birds” (Tilbury House) and “Birds of Aruba, Bonaire, and Curaçao: A Site and Field Guide,” (Cornell University Press).