American Birding Podcast



Happening NOW: The midsummer nocturnal molt migration of eastbound Chipping Sparrows

Note: “Happening NOW” is a series of occasional posts about avian “S&D” (status and distribution) on the continent. “Happening NOW” posts are brought to you by the editors of North American Birds (NAB), the quarterly journal of ornithological record published by the ABA. To learn more about NAB or to subscribe, please visit


It’s 4:36 a.m. on a muggy Monday morning in the Denver suburbs. Laptop in lap, I’m sitting outside on the back patio, working on file management for vol. 70, nos. 3 & 4, a combo issue, of North American Birds. It’s still 37 minutes till the commencement of civil twilight, more than an hour before sunrise.

A Chipping Sparrow migrates over Lafayette, Colorado. The author recorded this flight call from the back patio of his suburban backyard.

Then I hear it, a single, sharp, piercing call in the darkness: seen! It’s the flight call of a Chipping Sparrow, my FOS (“first of season”). The date is July 16, 2018; the bird is right on schedule. I’ve written before in this venue about mid-summer Chipping Sparrows where I live in Colorado, so I’ll be brief. Here goes. The species does not breed here. But it undergoes a midsummer nocturnal molt migration, starting around mid-July, with a decent trickle of the birds passing east directly over my rooftop.

I’ve had a proper understanding of this phenomenon for well over a decade now, but I’m still in awe of it. I grew up back East, where I “knew” that Chipping Sparrows don’t begin to migrate in earnest till early October. I had absolutely no idea that there was this sustained eastbound nocturnal migration across the western High Plains in frickin’ July.

How did I learn about this? In part, I would say, by being a devotee of North American Birds, the quarterly journal of avian “S&D” (short for status & distribution). As far as I am aware, the journal has never featured an article on the midsummer nocturnal molt migration of Chipping Sparrows, but that’s beside the point. The point is, The journal’s emphasis on S&D has inspired me and thousands of other readers to notice and wonder about bird populations.

Talk about “Happening NOW”! (That’s the title of this occasional series of posts to The ABA Blog.) Listening to nocturnal migration places me “in the present moment,” as the saying goes, more than any other birding experience I can think of. Hence this post. Now wouldn’t it be cool if phenomena like this one could be described more formally in North American Birds?

Answer: Yes, it would! Journal Editors Mike Hudson and Tom Reed and I, in consultation with S&D experts Tony Leukering and Paul Lehman, have been in discussion about overhauling the journal so as to emphasize short communications about recent and even ongoing population phenomena. (The regional reports would still be there, by the way, although perhaps transitioning to the electronic realm.) A key feature of these communications would be their timeliness; rapid review would be essential, and we’re playing around with the idea of electronic preprints followed by print publication soon thereafter.

What’s “Happening NOW” in your neck of the woods? Please use the COMMENTS section, below, to let us know.