The Snow Bunting is a small passerine bird that breeds in the Arctic tundra of North America and Eurasia. They are well known for their white winter plumage and their impressive migratory habits. Snow Buntings migrate enormous distances each year, traveling from their Arctic breeding grounds to wintering areas as far south as the northern United States. Their white winter plumage provides camouflage in the snowy Arctic environment.
Snow Buntings are sparrow-sized birds, measuring approximately 6-7 inches in length with a wingspan around 10-12 inches. Males and females have identical plumage. In winter, they are almost completely white except for black wingtips. In summer, they display brownish plumage on their wings and back with a black and white striped head pattern.
Snow Buntings are rare to see in many parts of their breeding and wintering range due to the remoteness of their Arctic habitat and nomadic winter movements. However, they can be locally common in certain coastal areas and agricultural fields. Their worldwide population is estimated at around 40 million individuals.
Let’s take a closer look at the rarity of Snow Buntings across different regions and seasons.
Breeding Range and Abundance
Snow Buntings breed in the high Arctic tundra of Alaska, Canada, and Eurasia. Their nesting habitat occurs from about 60°N latitude to the northern coastal limits of land, the species range map below shows their circumpolar Arctic distribution.
Snow Bunting Range Map
| By Christopher T Cooper – Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=27861055 |
During the short Arctic summer, Snow Buntings can be locally common nesting birds along coastal areas and inland tundra. However, the remoteness and inaccessibility of much of their habitat makes estimating populations difficult. Sources estimate their worldwide breeding population at around 40 million birds.
Breeding densities are highly variable based on the quality of habitat. Some studies have estimated populations ranging from 2 to 192 breeding pairs per square kilometer in optimal Arctic nesting areas. Overall densities likely average 10-30 pairs per square kilometer across their circumpolar range.
The graph below shows estimated breeding populations in different Arctic regions:
Estimated Breeding Populations by Region
| Region | Estimated Population |
|---|---|
| Alaska (USA) | 2 million |
| Canada and Greenland | 15 million |
| Russia (Siberia) | 12 million |
| Scandinavia | 4 million |
| Svalbard | 750,000 |
| Total | 34 million |
These estimates show that a majority of the world’s breeding Snow Buntings occur in northern Canada and Greenland, followed by Siberia. Smaller populations are found in Alaska, Scandinavia, and the Svalbard islands. Combined, these regions likely support a breeding population around 34 million Snow Buntings. The remaining birds occur in smaller numbers across other Arctic areas.
So in the remote tundra habitat preferred for nesting, Snow Buntings are common and locally abundant birds during the summer months. However, the sparse human population and limited access to much of their range still makes encounters rare for most people. Only researchers, Indigenous communities, and adventurous ecotourists regularly observe them in the Arctic.
Wintering Range and Abundance
During winter, Snow Buntings migrate out of the Arctic to subarctic and temperate regions across North America and Eurasia. They spend the winter months in open fields, grasslands, coastal habitats, and agricultural areas with low vegetation.
In North America, most Snow Buntings winter from southern Canada south to the northern United States. This includes all Canadian provinces from Ontario to British Columbia, with large concentrations around the Great Lakes and Pacific Coast. In the United States, they are rare and irregular winter visitors from Minnesota to Maine, and along the Pacific Coast.
Eurasian birds winter from Scandinavia and Russia south to central Europe and northern China. Major wintering areas include northern Scandinavia, northern Russia, Mongolia, northern China, Japan, Korea, and Kazakhstan.
Despite migrating long distances from the Arctic, Snow Buntings remain rare over much of their winter range. They occur in highly nomadic and unpredictable flocks seeking suitable habitat. Except for a few localized areas, most regions only host small numbers or occasional flocks each winter.
For example, Cornell Lab of Ornithology estimates the wintering Snow Bunting population in the contiguous United States at around 110,000 birds. They note that flocks of 10 to 100 birds are much more common than larger aggregations of 1,000+ birds. This highlights their scarcity compared to many other winter finches and sparrows.
Below is a table showing estimated winter abundances across different regions:
Estimated Wintering Populations
| Region | Estimated Population |
|---|---|
| Alaska (USA) | 250,000 |
| Canada | 12 million |
| Contiguous USA | 110,000 |
| Greenland, Iceland | 750,000 |
| United Kingdom | 22,000 |
| Scandinavia | 1 million |
| Northern Russia | 8 million |
| Mongolia, China | 2 million |
| Total | 24 million |
The table shows that the majority of the world’s Snow Buntings winter in northern Canada and Alaska, followed by northern Eurasia. More southern regions like the contiguous United States and United Kingdom host relatively tiny populations. So outside of a few winter hotspots, Snow Buntings remain a rare find for birders across most of their winter range.
Migration Abundance
The migrations of Snow Buntings are impressive feats. Birds breeding in Alaska and western Canada migrate east across Canada before heading south into the United States. Eurasian birds fly south and southwest to wintering areas. Round-trip migrations can cover 12,000 miles or more for some individuals.
Despite their long migrations, Snow Buntings are rarely abundant migrants. They travel in small loose flocks that often go undetected. Observation reports indicate the majority of migrating flocks number fewer than 200 birds. Only on rare occasions do Snow Buntings make migratory flights involving thousands of birds.
There are a few migration watch sites and geographic bottlenecks where Snow Bunting numbers can be more concentrated:
– Point Pelee, Ontario – up to 5,000 per day during spring migration
– Southeastern Manitoba – up to 15,000 per day during late October
– Western Alaska – up to 30,000 per day migrating west from Canada to Russia
Outside of these migration hotspots, the species remains a rare transient across most of the United States and Canada. Average birders may see them once a year or less during migration periods. Their nomadic movements and lack of large migratory flights make Snow Buntings unreliable migrants to find.
Rarity in the United Kingdom
The United Kingdom provides a case study in the Scarcity of Snow Buntings across much of their winter range. The UK is located well south of the core winter range, so only small numbers reach there annually.
According to the Royal Society for the Protection of Birds (RSPB), Snow Buntings are scarce winter visitors and passage migrants, occurring mainly in Scotland with smaller numbers in Northern England and Northern Ireland. They estimate that the UK holds around 1% of the world’s wintering population, or about 22,000 Snow Buntings.
The graph below from the UK Rare Bird Reports shows the maximum counted number of Snow Buntings by year from 1980-2020. It illustrates how annual numbers fluctuate but seldom exceed a few thousand birds:
Maximum Reported Snow Buntings – United Kingdom 1980-2020
| Year | Maximum Reported |
|---|---|
| 1980 | 725 |
| 1981 | 134 |
| 1982 | 55 |
| 1983 | 392 |
| 1984 | 194 |
| 1985 | 844 |
| 1986 | 561 |
| 1987 | 729 |
| 1988 | 137 |
| 1989 | 623 |
| 1990 | 463 |
| 1991 | 346 |
| 1992 | 662 |
| 1993 | 459 |
| 1994 | 432 |
| 1995 | 1837 |
| 1996 | 1811 |
| 1997 | 2029 |
| 1998 | 566 |
| 1999 | 953 |
| 2000 | 469 |
| 2001 | 939 |
| 2002 | 1159 |
| 2003 | 604 |
| 2004 | 1186 |
| 2005 | 256 |
| 2006 | 652 |
| 2007 | 910 |
| 2008 | 483 |
| 2009 | 1833 |
| 2010 | 1913 |
| 2011 | 469 |
| 2012 | 656 |
| 2013 | 646 |
| 2014 | 2288 |
| 2015 | 2892 |
| 2016 | 1475 |
| 2017 | 2425 |
| 2018 | 1220 |
| 2019 | 1653 |
| 2020 | 655 |
So even during the best years, Snow Bunting numbers in the UK do not exceed a few thousand birds. Most years see maximum numbers in the hundreds. This reflects their overall scarcity as a species that winters no further south than Scotland in normal conditions. Seeing even a hundred Snow Buntings in the UK makes for a notable winter sighting.
Conclusion
In summary, Snow Buntings are rare to uncommon birds across most of their range outside the breeding season. Their remote Arctic nesting habitat makes encounters difficult for most people despite large breeding populations. During winter and migration, Snow Buntings occur in nomadic and often small flocks that are easy to miss. Only certain Arctic areas, migration hotspots, and a few wintering sites host these birds in abundance each year. For birders and ornithologists across North America, northern Europe, and Asia, a sighting of a Snow Bunting flock represents a special winter highlight. Their scarcity over vast areas boosts their seasonal appeal as a species. Careful monitoring of populations will be needed as climate change alters the Arctic ecosystems where these unique buntings breed.
