Ron Pittaway has posted his annual winter finch migration forecast to the Ontario Field Ornithologists webpage. Winter finches are those species of the family Fringillidae that breed in the boreal forest of northern Canada and spend the winter farther south. While some migrate south every year, others follow an irregular migration pattern. They may stay in the boreal forest if sufficient food is available; or large flocks may migrate south in an irruption in years when food is scarce. Irruptions may reach into southern Canada and the northern United States. At other times finches will wander east or west, depending on available food sources.
Overall the odds of irruptions look better than last winter. I have excerpted the accounts for a few of the species more likely to reach the Northeast or Mid-Atlantic. Keep in mind as you read that the forecast is written primarily for birders in Ontario and neighboring provinces, so the probabilities need to be adjusted a bit for readers further south.
Pine Grosbeak: This grosbeak will irrupt south of the breeding range because crops on native mountain-ashes (rowan berries) are generally poor in northeastern Ontario and across the boreal forest. However, crops are good in northwestern Ontario west of Lake Superior. Pine Grosbeaks should wander south to Lake Ontario and perhaps farther in search of crabapples and planted European mountain-ash berries, which have average crops in southern Ontario. Watch for them at feeders where they prefer sunflower seeds. After irruptions, Pine Grosbeaks return north earlier than other northern finches. Most are gone by late March. Buds form a larger part of their winter diet when mountain-ash crops are poor.The report also includes notes on a few species aside from finches.
Purple Finch: Most Purple Finches will migrate out of Ontario this fall in response to the low seed crops. Currently, Purple Finches are migrating south through southern Ontario. Very few or none will stay behind at feeders in southern Ontario.
Common and Hoary Redpolls: There will be a big flight of redpolls into southern Ontario and bordering United States. Seed crops on white birch, yellow birch and alder are very poor in most of Ontario. Expect redpolls at bird feeders this winter. Far northwestern Ontario has a good white birch crop so redpolls may be common there.
Evening Grosbeak: This grosbeak will irrupt south of the boreal forest this fall because tree seed crops are generally very poor in northeastern Ontario and western Quebec. In recent weeks scattered birds have visited feeders in southern Ontario. Beginning in the early 1980s the Evening Grosbeak declined significantly as large outbreaks of spruce budworm subsided. The larvae and pupae are eaten by adults and fed to nestlings. Expect Evening Grosbeaks at bird feeders in southern Ontario and northern United States, but not in the large numbers seen during the 1970s.
Red-breasted Nuthatch: They have been moving south since mid-June presumably because of the poor cone crop in central Canada. Almost all Red-breasted Nuthatches will depart Ontario's boreal forest by late fall and left the province. Some will be at feeders in southern Ontario, but they will be very scarce in Algonquin Park. Algonquin Christmas Bird Counts (32 years) show a biennial (every two years) high and low pattern, with some exceptions.There may also be an influx of northern owls and other raptors depending on what happens with the small mammal population in northern Ontario. The report predicts that rodent numbers will be low this winter, but time will tell. I have already seen several red-breasted nuthatches this fall, which I think bodes well for a passerine irruption, in any case.
Bohemian Waxwing: The poor crop of native mountain-ash (rowan berries) in much of northern Ontario will cause Bohemians Waxwings to wander south and east this winter. Watch for them eating buckthorn berries and crabapples in southern Ontario. The mountain-ash crop is better west of Lake Superior with a big crop around Kenora at Lake of the Woods.
Gray Jay and Boreal Chickadee: They are moving in northeastern Quebec east of Tadoussac along the north shore of the St. Lawrence River. These movements could extend to southern Ontario and northeastern states.
Read the rest of the forecast for details on other species.
For more on winter finches:
- Photos of winter finch species
- The 1997-98 "Superflight" (animated maps of irruptions)
- 1994 Finch invasion in Garrett County, Maryland
- Winter Feeder Frenzy (notes on attracting finches)
- Winter Finch Forecast 2006-2007
- Winter Finch Forecast 2005-2006