Wild With Nature

Fall has come gently to the Helena Valley this year. Temperatures have floated well above average. Killing frosts and early snowstorms have been delayed. Nevertheless, fall bird migration has seemed to fly past. The flood of warblers has passed through and the golden cottonwood trees have become quiet. But although fall can be a bittersweet season, with so many goodbyes as the summer birds leave Montana, the frigid months ahead are far from sterile. Here are a few of the bird stories to watch for in the months ahead:

Golden eagle migration

Sometime in early to mid-October, migrating golden eagles stream southward from Canada. They fly past silently. Few of us notice them passing. But for anyone who looks, it’s a spectacular sight. Along with many other raptors, large numbers of golden eagles funnel along the mountain ridges. Here, steady westerly winds act like an elevator, keeping these soaring birds aloft with a minimum of flapping. In mid-October, a mind-boggling 300+ golden eagles can glide past Helena’s mountain ridges in a single day, streaming rapidly southwards over the wind-blown subalpine firs.

Golden eagles over the valley

On some of these mid-October days, it’s possible to see this flow of migrating eagles from the valley bottom, too. October 16, 2017 was one of those days. I was out at Sevenmile Creek, doing a bird survey among the stark gray stems of the now-leafless chokecherries. As the morning warmed up, I spotted a dark speck circling in the blue sky over the rocky bulk of the Scratchgravel Hills. Soon there was a second one: two massive golden eagles high above, circling on thermals of rising air fueled by the mellowing warmth of the autumn sun. The eagles left their thermals and glided southwest overhead, towards the Boulder Mountains and the invisible spines of the mountain ridges extending south beyond them. 

Through that day of valley birding, I counted 11 golden eagles as they passed by, riding thermals and streaming south. It was an impressive spectacle in itself – and one that I could easily have missed, had I not been scanning the skies for tiny specks thousands of feet above me. But it was also part of something larger, a flood of raptors pouring south out of Canada. On that same day, observers at Duck Creek Pass on top of the nearby Big Belt Mountains counted an astounding 394 raptors gliding past their viewing station.

Snow geese and tundra swans

As the weather turns towards freezing and the first storms of winter blanket the ground with white, listen for a shrill barking music in the air over Helena. It’s the snow geese, passing overhead in uneven vees. With them, listen for the plaintive calls of the tundra swans and the trumpeter swans with their deep-throated barks. 

The passage of the geese and swans may not last long, but it’s incredible to behold. And when it comes to swans and snow geese, October 27, 2019 is a day that remains vividly in my memory. It was a morning that began with heavy frost. The ground was still covered with a thin layer of snow from a storm two days before, and the forecast called for temperatures falling to 0°F the following week. A handful of Last Chance Audubon Society volunteers and I had special permission to do yet another bird survey at Prickly Pear Land Trust’s Sevenmile Creek restoration site. Earlier in the month, we had watched golden eagles soaring through this airspace over the Scratchgravel Hills. Now, in their place, we were spotting snow geese and swans. A lot of snow geese and swans. 

Heading south

The swans came first, traversing the sky in small, vocal flocks. Often we saw our two species mixed together, a handful of the larger trumpeter swans leading a larger echelon of tundras. 

Next came the snow geese. They were flying higher than the swans, and in larger groups. Often we would glimpse a flock of them impossibly high overhead, their brilliant white bodies contrasting with their black wingtips, and then watch them disappear above the scattered stratus clouds that hung over the valley.

It was the sort of day when the birds kept coming, fast, and it took all five of us working together to count them. Our ears were tuned for the music of swans and high-flying geese. We scanned the northern sky, snapped photos as the flocks streamed past, and tried to count every single bird. And from our single site at the edge of the Helena Valley, when we tallied up the numbers, it was clear that the waterfowl were on the move. 322 trumpeter swans. 1,686 tundra swans. 1,105 snow geese. All of them flying powerfully south, navigating along the rocky backbone of Montana.

American tree sparrows

As winter settles in and the landscape relaxes into slow dormancy, American tree sparrows appear in the Helena Valley. The first tree sparrows of the fall generally arrive in October, flying south by night from their summer nesting places in the willows and spruces near the Arctic treeline. Small flocks stay with us throughout the winter, frequenting weedy, brushy places with a mix of shelter and seeds.

Watch for American tree sparrow flocks around patches of orach (Atriplex heterosperma), giant-seed goosefoot (Chenopodium simplex), pit-seed goosefoot (Chenopodium berlandieri), and kochia (Kochia scoparia). (Check out this video for some more information on our winter tree sparrows.) These dry, tan patches of weedy annuals are loaded with seeds. It’s common to first notice the tree sparrows by their calls, a sharp tip and a slightly less-common, warbled switlit. If you hear these calls, watch the bushes and weeds closely. There’s a good chance that there are a few dozen tree sparrows within, quietly stocking up on food to make it through the harsh cold snaps ahead.

And if you’re patient, you’ll be able to spot one of these gorgeous birds alighting in the tops of the goosefoot. Look for the neat black dot in the middle of the wintry gray breast. Notice how the bill is half-gray and half-yellow. And admire the sharp chestnut markings on the head before the tree sparrow flies, returning to seed-feeding in the cover of the dead annuals.

Rough-legged hawks

As the golden eagles of October glide silently past Helena, they bring with them another visitor from the far north. Rough-legged hawks spend their summers in the arctic. Montana is their idea of Arizona: a “mild” place to spend the winter. And as long as the snow doesn’t get too deep or too crusty, dozens of them can be found in the Helena Valley through the cold months. Rough-legged hawks are crisply patterned hunters. They’re the colors of winter: black shoulder patches like the long, cold nights and brilliant white flight feathers like the glare of the sun on the snow. They perch on fence posts, power poles, and in the very tops of trees and shrubs, scanning the snow that covers the valley. On a windy day, they’ll hover over the quiescent grasses, scanning the fields for mice and voles. 

Bohemian waxwings and their predators

As we reach November and the possibility of winter storms grows higher, watch for the arrival of these sleek, black-masked fruit-eaters. The fall and winter movements of Bohemian waxwings are notoriously variable from year to year, depending on where fruit can be found. In certain rare “irruption” years, massive numbers have appeared as far south as New Mexico.

Around Helena, bohemian waxwings are regular winter visitors. But here, too, numbers can be highly variable. In 2005, observers on the Last Chance Audubon Christmas Bird Count (CBC) reported over 16,000 bohemian waxwings around Helena. But in 2018, CBC observers only counted 20. 

Waxwings and fruits

In certain years, I’ve watched flocks of over 1,500 bohemian waxwings in the midst of Helena, feeding on winter fruits in peoples’ yards. Which fruits do they eat? Around Helena, the primary attractions seem to be Rocky Mountain junipers (Juniperus scopulorum), European mountain-ashes (Sorbus aucuparia), Russian-olives (Elaeagnus angustifolia), and crab apples (Malus sylvestris). The presence of cities on the Montana landscape has changed the winter fruit scene substantially. Of these four shrubs, only junipers are native. European mountain-ashes, Russian-olives, and crab apples are all widely planted ornamentals. Russian-olive has also become very widely naturalized in Montana, where it can pose threats to native plant communities.

Small flocks of bohemian waxwings can be incredibly tame, allowing us to get a close look at their chestnut butts, their yellow-tipped tails, and the waxy red spots in their wings. But large flocks are incredibly nervous, ready to fly at the drop of a pin. Why? All of these fruit-eaters attract predators. Around Helena in the winter, it’s common to see a merlin or a sharp-shinned hawk sneaking up on a waxwing flock, searching for a feathery meal.

Stories of our winter birds

As winter inches closer, it’s a time of slowing down. The days grow shorter. The leaves glow brilliantly for an instant, then drift to the ground. Our summer birds have left, our plants have shifted to dormancy, and our wood piles are ready for the cold. But there’s beauty to be found in the changing – and the quiet of winter isn’t as quiet as you might think. So as our hemisphere turns away from the sun, keep your eyes open for the feathered harbingers of the season. Watch for golden eagles, snow geese, and swans passing high overhead. Get to know our winter birds and the patterns of their lives. And as you do, consider that these rhythms of the landscape are stories people here have been noticing for many thousands of years.

What do these stories mean to you?