This report has been updated for 2018.
As winter approaches the migratory birds-warblers, vireos, blackbirds, and hawks-depart. Resident birds, chickadees, titmice, cardinals and the like persist, but we dearly miss the departed. Fear not. Our winter migrants, the winter finches and their allies, will arrive shortly. Or not. The birds known collectively as winter finches are irruptive species, appearing in Vermont in some years, but not others. Predicting their movements has become a cottage industry of sorts, and no one forecasts better than Ontario’s Ron Pittaway.
Winter finches are members of the family Fringillidae, which includes Pine Grosbeak, Common Redpoll, Pine Siskin, and Evening Grosbeak, as well as the crossbills, Red Crossbill and White-winged Crossbill. These birds live and breed in the boreal forests of Canada and northern New England, but breed sparingly, if at all in Vermont. Other finches that are Vermont breeding birds such as American Goldfinch, House Finch, and Purple Finch, while interesting and nomadic, will not be covered here.
A review of the CBC results from the Burlington Circle from 2006-2010 demonstrates the irruptive behavior of four winter finches.
|Species (record, year)||'06||'07||'08||'09||'10|
|Common Redpoll (908, 1965)||0||63||0||0||61|
|Pine Siskin (130, 1987)||0||1||75||0||16|
|Pine Grosbeak (244, 1985)||0||196||0||0||0|
|Evening Grosbeak (920, 1980)||0||0||0||0||0|
Why do the winter finches irrupt? The short answer is food. When food supplies in Canada are exhausted, these birds migrate southward in search of food. Thus, knowledge of their food preferences and the status of crops in Canada and the United States in any given year is the key to forecasting irruptions. Here is a summary of this year’s predictions based on Ron Pittaway’s recently released finch forecast. A useful guide to the identification and behavior of winter finches can found at http://www.jeaniron.ca/2011/WinterFinches.pdf .
The morphological hallmark of Common Redpolls is the red patch on their crown, hence the name. These sparrow-sized birds of the genus Carduelis sport a stubby yellow beak, broad streaks on the flanks, and a dark face. Rarely, Hairy Redpolls intermingle in flocks of Common Redpolls. Hoary Redpolls are slightly larger than their cousins and noticeably paler. Recently though, doubt has been cast on the validity of the distinction between these species. Regardless, spotting one of these frosty little birds adds excitement to the search for Common Redpolls.
Redpolls are birch seed specialists. When birch seeds are abundant in Canada redpolls stay north; when birch seeds are scarce, redpolls irrupt. In our local CBC data Common Redpolls were counted in 2007 and 2010, but not in the intervening years. This year’s forecast calls for more redpoll numbers than recent years, since the birch seed crop in the Northeast is good. Redpolls will come to feeders, too, preferring nyger (thistle) and black oil sunflower seeds.
These nomadic little finches are distinguished by their slender beak, heavy breast streaking, and yellow wing and tail markings. Pine Siskins feed mainly on seeds, especially spruce seeds, but also the seeds of birches, alders, and pines.
Since the cone crop of spruce seeds in the Northeast is excellent this year, it is expected that siskins will wander south in large numbers and should be locally common in Vermont. A few isolated reports of Pine Siskins in Vermont have appeared in the VT eBird database already, especially in the Northeast Kingdom. We look forward to their appearance in northwestern Vermont. Their search is on.
These large finches in the genus Pinicola are hard to miss. Males are large-headed, short-billed, and uniformly pinkish-red on the head, back, and breast. Females are equally distinctive showing subtle yellow-green markings on the head and back and a gray breast. In Newfoundland Pine Grosbeaks are often referred to as “Mopes”, highlighting their lethargic behavior while feeding on their preferred food, mountain-ash berries. From a birders point of view lethargy is a good thing.
2007 was a banner year for Pine Grosbeaks in Vermont. In between, nothing until 2012 when 193 Pine Grosbeaks appeared in the Burlington CBC. I took the photo above at Technology Park in South Burlington in 2012, where a flock of Pine Grosbeaks was feasting on crab apples. This year most Pine Grosbeaks will likely stay north of Vermont, since the mountain-ash berry crop in the northern Canada is above average. However, buckthorn berries, ornamental crabapples, and perhaps sunflower seeds may entice a few Pine Grosbeaks to visit Vermont late in the season when northern food sources are depleted.
This handsome finch, which was the ABA Bird of the Year in 2012, occurs regularly in the eastern parts of Chittenden County, such as the Birds of Vermont Museum in Huntington, but infrequently appears in the Burlington area. Still, in the 1980 CBC in the Burlington circle 980 Evening Grosbeaks were counted. Both sexes of this large finch are large-billed. The yellow cast to the male’s body, his yellow eyebrow, and white secondaries make identification of this bird straightforward. Females are less gaudy and are gray overall with a greenish nape and a large pale bill.
Evening Grosbeak populations fluctuate with spruce budworm outbreaks and populations have declined as the effort to control spruce budworms has expanded. However, in the past few years increased numbers of spruce budworm outbreaks have increased the breeding success of Evening Grosbeaks. A few reports of Evening Grosbeaks at feeders in northeastern Vermont might herald the arrival of more of these handsome birds throughout the state. Evening Grosbeaks in Vermont collect at feeders in large flocks, feeding voraciously on sunflower seeds. Therefore, it might be wise to lay in an extra supply of sunflower seeds this year to prepare for the arrival of these handsome finches.
Red and White-winged Crossbills nest in the boreal forest of the Northeast Kingdom in some years. The unusual configuration of the crossbill’s beak is a unique adaptation designed to pry seeds from the cones of conifers. Red Crossbills specialize in pine cone seeds, whereas White-winged Crossbills specialize in spruce cones.
Crossbills seldom appear in the Champlain Valley in December. A single White-winged Crossbill was reported in the Burlington CBC in 2008 and only 2 were reported in 2010. The record of 9 White-winged Crossbills was set in 1963. Red Crossbills have been dropped from the CBC list, having not been counted for over 20 years. Nonetheless, 19 Red Crossbills were counted in the 1985 CBC so hope springs eternal.
White-winged Crossbills occur at feeders in the Champlain Valley sporadically, a rare treat. Since spruce cone crops are bumper in the Northeast this year, White-winged Crossbills will likely be in evidence in the NEK and possibly elsewhere in the state. Likewise, Red Crossbills have already been reported in various parts of Vermont and a significant late irruption throughout the state is possible.
There you have it. Remember, predictions are just that and no more. Whether these predictions will prove to be accurate is unknown. Validating the Pittaway forecast with actual sightings is half the fun. Be on the lookout for this year’s migration of winter finches, the happy wanderers of the north.
Photo of Common Redpolls in Jericho by Jim Morris