08 February 2025

Snow Buntings

Snow Buntings

“A sturdy chubby-faced bunting of cold open places that melts into winter landscapes and explodes into white flight.” – Pete Dunne*

We had an extended period of cold in late January and early February, and with a little snow, it made it feel like a real winter, for a change. The snow depth is still far below historical averages, but slowly catching up.  Wildlife seems to be responding to the change. I can now see deer tracks in our woods, as they meander in search of twigs to browse on, working harder to fight off hunger. Red Foxes are leaving tracks in our fields that trace their nightly foraging runs to the creeks. I’m using some inference on this, because it’s a bit hard to tell what species it is when the snow is dry and powdery.

One of the interesting cold-season phenomena in our area is Snow Buntings.  They regularly show up in Vermont in winter, having descended from their breeding grounds way up in the Arctic. The “snow” in the name operates in two ways: they arrive when our fields are covered with snow, and they are a lot whiter than most other songbirds. Their winter garb is beautifully patterned, making them a welcome sight in a lean winter. In Pete Dunne’s words, they “blend the colors of a snow-whipped weedy field or a cobble-strewn beach.” They roam through farm fields looking for weed seeds to gather. They tend to collect in small flocks as they forage, and frequently show up near farmhouses and along roadsides. I don’t know if they are as irruptive as the “winter finches,” (the Redpolls, Pine Siskins, Evening Grosbeaks, Purple Finches, and Pine Grosbeaks, among others). The winter numbers of finches fluctuate wildly from one year to the next. It is thought to be due to the quality of the cone crop in the north. Some observers are compiling information of this type to make forecasts of the flock sizes moving south.

Snow Bunting in Maryland, Sandy Point State Park, January 2019.

Snow Bunting numbers also fluctuate, but with the difference that there are at least some of them around every year. The situation is a bit different, because they spend summers in Arctic tundra, farther north than most cone-bearing plants. The Snow Bunting is the northern-most passerine species of bird. It spends the breeding season in the realm of sedges, mosses, lichens, wildflowers, and dwarf shrubs. So it must head south every winter, not just the occasional winter.

A winter-plumaged bird at Shelburne Bay, Vermont, November 2024

If not irruptive, though, they still have invasion years. In my handful of recent northeastern winters, I have seen small numbers, scattered groups of a few dozen. But Vermont records show that in 1989, 2011, and 2018, these flocks grew to very large size. There are two possibilities: that the species has major invasion years, or that conditions cause the flocks to concentrate. Either way, the results can be impressive. The year 2011 brought a flock of 1000 to Walpole, NH, in the Connecticut River Valley. Central Massachusetts had a flock of 4000 in 2018. In 1989, Charlotte, in Vermont’s Champlain Valley, had a flock of 2000 in the third week of January. But further east, in Monkton, the birds congregated in an enormous flock that was estimated at 8,000-10,000. Flocks like that cannot be easily counted, so this is only a rough estimate.

This year, my first encounter with the species was at Shelburne Bay on Lake Champlain, where 5 birds flew past on November 16. Closer to home, a flock of 30-40 birds was present just down the road in the first half of December. We saw a similar-sized group on the New Hampshire coast on December 31. The neighborhood flock re-appeared in mid-January, where they seem to be attracted by weedy patches at the edge of cornfields. (Patches not yet denuded by Round-up!) In the Connecticut River Valley south of us, near Hanover, a flock of a few hundred was noted in early January. Near Newbury, Vermont, birders noticed a large group in farm fields in late January, on both sides of the state line. Things began to look exciting on January 26, when 910 birds were counted in a farm field on the New Hampshire side. This group grew in recent days, until a huge flock numbering in the thousands became evident on February 3.

I decided to pay a visit a few days later. I saw them flying past as soon as I opened the car door. Moving in the fields on both sides of Newbury Crossing Road, they took on the appearance of a swirling mass of white-and-black birds in the air, recalling coastal flocks of shorebirds or blackbirds. Something seemed incongruous, however, about the reality that these were buntings, not blackbirds. It was astounding. Snow Buntings have a soft twittering call often produced in flight, and with so many in the flock it could be heard clearly even at a distance of a few hundred meters. I made a weak attempt at counting them, by taking a few photos in the main part of the flock. It’s almost impossible to come up with accurate numbers when the flock is frequently in motion, but one photo shows 2000, and there were more all around. Other birders estimated 6500 Snow Buntings that day, and they thought that was a conservative estimate.

The flock in Newbury, Vermont, February 2025

Before this day, the largest number of Snow Buntings I ever saw was 50. This was – to use a trite phrase – a quantum leap in my experience of this species.

Snow Bunting ornaments on a tree

Why did the birds decide to camp out at this place, Newbury Crossing Road? One clue is that the fields were planted with pumpkins the previous summer. The birds were foraging on weed seeds of a head-high weed plant that was sparsely distributed in the fields. The snow was littered with fallen seeds, as my photo shows. This could be a weed that happens to do well in pumpkin fields. Or perhaps the Snow Buntings like the juxtaposition of open field with river. In my neighborhood, there is no shortage of open fields that might attract Snow Buntings, but I’ve only found them in two places. Both of them are grazed but not actively hayed, which gives rise to weeds that persist above the snow cover. That seems to be the key ingredient.

A weed stalk in the field in Newbury. Fallen seeds cover the snow surface, along with tracks of buntings and larks.

Accompanying this flock were about a hundred Horned Larks, and a handful of Song and American Tree Sparrows. Braving the cold air, I scanned with my spotting scope through the lark flock and eventually pulled out one Lapland Longspur, another arctic breeder. That was a great find – I’ve seen this longspur only a few times in my life. Longspurs can also form large winter flocks, but this individual seems to have lost his.

 *Pete Dunne's Essential Field Guide Companion, Houghton-Mifflin, 2006.

 

 

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