A Tale of Two Bird Counts

WC has participated in a fair number of Christmas Bird Counts. For non-birders, the Christmas Bird Count is an annual census of birds, a citizen science project that has been held during the Christmas holidays for some 120 years now. It provides one of the longest baseline studies of populations of bird species across North America. The idea is to send volunteers out into a fifteen-mile diameter circle to see and count every bird they can.

Boise, Idaho Christmas Bird Count Circle

In Boise, WC’s adopted home, the count circle centers on the Capitol Dome in downtown Boise. The fifteen mile diameter circle gets a nice sample of urban, suburban, foothills, sagebrush and river habitats, including a couple of small reservoirs, across a 3,000 vertical foot elevation range. In Fairbanks, the habitat is much less diverse.

Fairbanks, Alaska Christmas Bird Count Circle

WC, as readers know, is a mildly obsessive bird photographer. One of his motivations for relocating to Boise was more species diversity, especially in the winter. The Christmas Bird Counts demonstrate just how different the birding is. The 2014 Fairbanks Christmas Bird Count, the last one for which WC was the compiler, counted 26 species of birds, pretty respectable for the sub-Arctic, boreal forest in late December.1 By contrast, the 2020 Boise Christmas Bird Count found 104 species, exactly four times as many. Those species included a Wilson’s Snipe, seen by WC and Mrs. WC.

Wilson’s Snipe, Ada County Fairgrounds, Garden City, Idaho
Photo by Mrs. WC

And conditions were surprisingly challenging in Boise this year: freezing fog limiting visibility to a quarter mile or less most of the day. Along the Boise River corridor, in our assigned area, sometimes you couldn’t see the tree tops for the fog. The fog froze to the paved trails, too, turning them into a skating rink. Not the same, WC will admit, as a Fairbanks bird count at -50° F or so, but still.

Fairbanks does lead Boise in a couple of categories, though: in 2014, it mustered some 112 volunteers. Boise, with a much, much larger population, could manage only about 80. On the other hand, the longer daylight hours in Boise permit a longer count day, so the hours of effort – time each participant spends looking for birds – is much longer.

There are some 2,300 Christmas Bird Counts around the world now. The Boise one has been running for more than 50 years. Fairbanks has been running one for 60 years, so it passes Boise there, too.

The highlight for WC of this year’s count? Either the Wilson’s Snipe above or the two Anna’s Hummingbirds coming to our (heated) hummingbird feeder.

Anna’s Hummingbird subadult, Boise, Idaho

If you’ve done a Christmas Bird Count, thanks. WC hopes you had as much fun as he does. If you aren’t participating, you should consider it. If you aren’t a birder, you can be teamed up with one (in that future COVID-free world) for help. Fresh air, exercise to work off all that Christmas candy, and the wonderful delight of seeing birds.

1 The Fairbanks total is inflated somewhat by the Chena 5 Powerplant in downtown Fairbanks. The cooling water from the powerplant is discharged into the Chena River. The warm water plume keeps the river open for a couple of miles downstream. The open water supports six waterfowl species that otherwise would be absent.

5 thoughts on “A Tale of Two Bird Counts

  1. My count was on 1/2/21. Best bird was a Spotted Towhee, a good find for St. Louis, and a lifer for the two beginner birders that I had invited to join me. I had found a Snowy Owl on 1/1/21, in the count circle, but it wasn’t refound on the 2nd. Argh! Thank you for being a compiler, and for today’s post!


  2. WC
    Why not postpone a Bird Count on a foggy day or other inclement weather that makes is difficult to count accurately? Does the need for same-day count (inter)nationally outweigh local factors like that? If so, does the local venue note its special conditions potentially affecting accuracy?
    paul eaglin


    • The variables affecting CBC counts are numerous: number of birders, number of groups, number of feeder watchers vs. field observers, time spent observing, owling time vs. general birding time, observer skills at plant ID and at estimating bird numbers, weather, cars getting stuck, weather, birders clustering at rare finds, weather, finding new sites where the birds have been all along, and weather, to mention a few. Many of these factors are recorded when the results are compiled. Others are harder to deal with. I remember one winter when a count with newly discovered winter roosts of American Robins reported more robins than had ever been reported in the whole state before. The main things the counts have going for them, statistically, are that they are numerous and most have been going on for decades. Therefore, some trends show up despite all the complications.


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