This winter, I spotted a flock of feisty little white-feathered birds angling in, out and sideways over a hayfield in Dixmont, and after a moment of wonder realized they were snow buntings.

By now, they’re long gone from Maine. The males have been at their breeding grounds in the Arctic for weeks, and many of the females have just arrived.

Plectrophenax nivalis, as they’re called by the ornithologists, have the northernmost range of any passerine, or perching bird. Audubon notes they’re sometimes nicknamed “snowflakes” because of how they flock and swirl over winter fields.

Central Maine is in about the middle part of their southern nonbreeding range, according to a Cornell Lab of Ornithology map.

They forage on tundra and grasslands for seeds, insects and spiders, and nest on the ground.

A flock of snow buntings in southern Ontario, Canada. Photo courtesy of willemspan/GBIF

Some researchers with the Canadian Snow Bunting Network in central Canada have tagged snow buntings to try to learn the migration patterns, and discovered a couple of interesting things. One was that the birds tend to come back to the same places for the winter, but while there, they travel up to hundreds of kilometers from the wintering site and back.

In past winters, I’ve seen snow buntings in that same area in Dixmont, and a reader in Kents Hill seemed to corroborate this place-specific return, too.

“We see a flock of snow buntings several times each winter near our home,” he wrote to me. “They are always focusing on a long gravel driveway, after the wind has swept it clear of snow and ice. On the ground for 10 to 15 seconds, then as a cluster in the air for a minute or so, repeating a couple of times, then gone. Flock size about 20.”

One of the researchers told a reporter they hardly ever saw females around Winnipeg, Manitoba, whereas in Windsor, Ontario, they recorded mostly females.

Another interesting observation made by the Canadians was that the flocks tended to be segregated by males and females, and the males tended to gather in colder locations. Females were hardly ever seen around Winnipeg, Manitoba, one of the researchers told a reporter, while females were mostly recorded in Windsor, Ontario.

The males, in particular, seem particularly adapted to far-northern cold. It turns out snow buntings have not been as thoroughly studied as many other birds, but one study looking into possible physical adaptations found there were small differences in blood and muscle tissue between pre-breeding and wintering individuals, but not strikingly so.

Another study found more large male snow buntings than female or smaller birds were captured in colder and snowier weather, suggesting the larger birds are hardier.

This led the researchers to speculate that a warming Arctic could spell trouble for birds specially adapted to cold weather. Recent estimates indicate snow bunting populations declined by 38% between 1970 and 2014. But many other bird populations were harder hit in that span, often as a result of habitat disruptions and advancing changes in climate, and overall snow buntings are a species of low conservation concern.

This is heartening, if not the best possible news, I guess, because they brighten up those winter fields, and it’s much better for all concerned if they keep doing that.

Dana Wilde lives in Troy. You can contact him at naturalist1@dwildepress.net. His book “Winter: Notes and Numina from the Maine Woods” is available from North Country Press. <https://www.northcountrypress.com/winter.html> Backyard Naturalist appears the second and fourth Thursdays each month.