American Birding Podcast



Happening NOW: Mountain Birds on the Move, But How Extensively?

This past Friday at a local hotspot in Boulder, Colorado, I was mildly surprised by a Williamson’s Sapsucker. The species is routine in the warmer months in the mountains in the western part of my county, but I’d never seen one east of the foothills. A quick check of eBird confirms it:

Williamson’s Sapsuckers are routine in the high country of western Boulder County, but unrecorded east of the foothills. Was a recent sighting east of the mountains part of a larger irruption of birds from the high country? If so, how extensive is the phenomenon?


The next morning, a hazy Saturday, while I was in the process of packing the kids into a car (soccer of course), I heard a Pygmy Nuthatch jabbering from a shade tree across the street. Like Williamson’s Sapsuckers, Pygmy Nuthatches are expected in the pine forests to the west but practically unheard of elsewhere. As far as I am aware, this was the first Pygmy Nuthatch in town.

On Sunday, I had a bit of time to kill in between my kids’ camps, so I popped on over to a local migrant trap. No eastern vagrants for me, but I did come upon one or two Brown Creepers. We get those in migration, but typically later in the season. At this time of the year, they’re generally still up in the mountains.

And yesterday morning, while dealing with getting the kids off to school, I was pleased to note an Evening Grosbeak winging its way over the park down the street. It was only my second Evening Grosbeak ever in the neighborhood. And no sooner had the Evening Grosbeak disappeared from view (and earshot) than did I hear a Mountain Chickadee calling hoarsely from the maple tree out my front window.

This is the time of year when one looks for Sabine’s Gulls and Clay-colored Sparrows, not visitants from the high country. Nevertheless: Williamson’s Sapsucker, Pygmy Nuthatch, Brown Creeper, Evening Grosbeak, Mountain Chickadee, all montane species, all in the lowlands around home, all in the space of 72 hours. Call it a trend?

To be sure, I’m not the only person noticing it. The state listserv is lighting up with reports of birds wandering from the mountains and foothills—especially Red-breasted Nuthatches and Woodhouse’s Scrub-Jays.

What’s going on? How extensive is the phenomenon? And what’s causing it?


Short answer: I don’t know. But I’m looking forward to reading about it, in due course, in North American Birds (NAB), the quarterly journal of ornithological record, published by the American Birding Association.

Sure, the data are out there already. I mean, I’ve already uploaded my eBird checklists. Folks are already posting about it on the state listserv. And I just now caught an allusion to it on Twitter. That’s great. But that’s also not the end of the story. The end of the story—or, at least, the part of the story that results from analysis and synthesis—is what appears in NAB.

I’m as devoted to eBird and online social media as the rest of you. But this is apples and oranges. NAB delivers a product that other knowledge providers cannot. By all means, contribute to eBird; post to the listservs; tweet and retweet about birds. And then get the full analysis and discussion at NAB.


NAB update. We’re a bit behind with production. But it’s for a good cause, if you will. That’s because we’ve spent a fair bit of time rejiggering the whole file management system at the journal. Vol. 70 no. 1 goes to press shortly; and then we expect the rest of vol. 70 to follow quickly.

If you’re already a subscriber: Thank you, and hang in there.

We’ll leave you with a tease: The photography in vol. 70 no. 1 is glorious. It seems that every field birder in North America carries a digital camera nowadays, and we’re gratified that so many excellent photos will grace the pages of the next issue of NAB.

—Ted Floyd, Managing Editor, North American Birds


Note: This is another in a series of blog posts from the editors of North American Birds. The idea of these occasional posts is to highlight ongoing bird population phenomena of broad interest to birders and field ornithologists across the continent. Full analysis will appear in print in North American Birds. To learn more or to subscribe, please go online: