The Common Redpoll (Acanthis flammea) is a small songbird in the finch family. It is a Holarctic species, breeding in northern regions of Eurasia and North America and migrating south in winter. Redpolls are boreal habitat specialists, preferring open coniferous forests, thickets, and birch stands. Their range extends into the arctic tundra. Redpolls are irruptive winter migrants that appear sporadically in more southerly regions when food supplies further north are scarce. This article explores the range and distribution of Common Redpolls across their breeding and wintering grounds.
Breeding Range
The Common Redpoll breeds across northern latitudes of the Holarctic region. Its breeding range extends from northern Europe across Asia to Alaska.
In Europe, it breeds in Iceland, Scandinavia, northern Russia including Novaya Zemlya, and northern Kazakhstan. The range extends as far south as central Scotland, southern Finland, Estonia, northern Belarus, and central Russia.
In Asia, the range covers northern Russia across Siberia to the Pacific coast. It breeds south to about 60°N latitude, including central Russian and northern Mongolia and northeast China.
In North America, Redpolls breed from Alaska across northern Canada to Labrador and Newfoundland. The southern limits reach central British Colombia, central Alberta, central Saskatchewan, southern Manitoba, northern Ontario, central Quebec, and Newfoundland.
Alaska and Canada
In Alaska, Common Redpolls breed throughout the mainland and islands except for the Aleutian Islands. They are abundant breeders in open birch and spruce forests.
They breed across Canada from the Yukon and Northwest Territories east to Newfoundland and Labrador. They are most abundant in the boreal forest belt that stretches across the provinces. Breeding is centered in the taiga and open conifer forests, with a preference for spruce and birch. Densities are lower in the prairie regions.
Eurasia
In Eurasia, the breeding range covers northern Scandinavia, northern Russia including Siberia, and northeastern Kazakhstan. The range extends as far west as Iceland and as far east as the Pacific coast.
Redpolls breed throughout Finland and the Baltic countries north of 60°N latitude. In Russia, they breed from the Kola Peninsula across Siberia to Anadyrland and the Kamchatka Peninsula. They are numerous breeders across this vast region in open conifer and birch forests and woodlands.
Wintering Range
In winter, Common Redpolls move south of their breeding range. However, they generally remain in the northern latitudes. Their winter range is highly irruptive, varying greatly from year to year depending on food supplies.
North America
In North America, the core wintering range is across southern Canada from British Colombia to southern Ontario and Quebec. In irruption years, numbers increase dramatically further south into the northern United States, south to Texas and Virginia.
Nomadic flocks wander widely in search of birch and alder seeds. They frequent weedy fields, woodland edges, thickets, and birch stands. Major irruptions occur at intervals of 2-4 years.
Eurasia
In Eurasia, most redpolls winter in a broad band across northern Europe and Russia, generally between 55°N and 65°N latitude. This includes southern Scandinavia, the Baltic countries, Belarus, northern Ukraine, southern Russia, northern Kazakhstan, and northern Mongolia.
In irruption years, larger numbers move farther south to central Europe and the Mediterranean region, as far as northern Africa and the Middle East. In Asia, irruptions can reach as far south as northern India and northern China.
Key Wintering Regions
While nomadic and irruptive in winter movements, several key regions host significant wintering populations of Common Redpolls in most years:
Canada
Southern Canada has very high winter densities, particularly from British Colombia to Ontario. Key provinces include:
– British Colombia: weedy fields of the Fraser River Delta and southeastern corner
– Alberta: North-central region including areas near Edmonton
– Saskatchewan: Southern third of province
– Manitoba: Southern regions including Winnipeg area
– Ontario: Southern areas north of the Great Lakes
Northern U.S.
In irruption years, large numbers reach the northern states, especially:
– Minnesota
– Wisconsin
– Michigan
– Washington state
– Montana
– Maine
Northern Europe
– Southern Scandinavia including southern Sweden and Norway
– Baltic countries: Lithuania, Latvia, Estonia
– Finland and northwestern Russia
Western Asia
– Northern Kazakhstan
– Southern Russia east of the Urals: Chelyabinsk, Kurgan, Omsk regions
Habitats
Common Redpolls use a variety of open habitats in winter, often associating with birch or alder stands:
– Fields and meadows with low vegetation and weed seeds
– Forest and woodland edges
– Roadsides with brush and thickets
– Early successional forest habitats with birch and willow
– Mature open coniferous forests with birch or alder understory
– Orchards and backyards with birch or weedy vegetation
They frequent sites with catkins and seeds of birches, alders, and willows. Weed seeds are also a major food source. They often mix in flocks with other finches like goldfinches and siskins.
Movements and Irruptions
Redpoll winter movements are highly nomadic and unpredictable. They wander widely within their winter range in search of ephemeral food sources.
This leads to periodic irruptive migrations in which large numbers shift out of the far north to more southerly regions, resulting in a substantial winter range expansion. The timing and intensity of irruptions are highly variable and poorly understood.
Several factors may trigger irruptions:
– Declining birch or conifer seed crops in the far north
– Early, heavy snow cover restricting food access
– Low autumn seed production across the breeding range
– High predation or competition pressure
During irruptions, redpolls may appear as far south as California, Texas, Virginia, the UK, the Mediterranean, northern Africa, and China. Movements are highly nomadic and flocks range widely during winter.
Irruptive winters see counts increase exponentially in key regions. For example, the Great Lakes region may host only a few thousand redpolls in a normal winter but several million birds during a major irruption event.
Population Counts
Due to their irruptive nature, estimating Redpoll populations is challenging. The table below provides rough population estimates:
Region | Breeding Population Estimate | Normal Winter Population Estimate | Irruption Winter Population Estimate |
North America | 15 million | 20 million | Up to 150 million |
Eurasia | 45 million | 50 million | Up to 500 million |
As shown, the wintering population may increase by an order of magnitude during major irruption events. However, these estimates are approximate given the species movements.
Conclusion
In summary, Common Redpolls breed across the northern Holarctic region in boreal and arctic habitats. They winter nomadically across more southerly latitudes of Canada and northern Eurasia, inhabiting open country with birch and alders.
Redpoll winter distributions are highly variable and irruptive in nature, as birds periodically shift south in search of food. During irruptions, large numbers may reach the northern United States and central Europe. Within their broad winter range, redpolls are mobile and concentrated in areas with abundant food sources like catkins and weed seeds. Their habits make populations difficult to accurately survey. However, redpolls are a widespread and often abundant winter finch across the higher latitudes of the northern hemisphere.