The 120th CBC in Wyoming

All 20 of Wyoming’s CBCs were conducted for the 120th Christmas Bird Count, and 81,367 birds of 113 species were recorded. The number of species typically ranges from 110 to 133, so CBC-120 was somewhat in the lower end of the spectrum.  

Casper had the highest number of species (63), followed by Jackson Hole (60), Story-Big Horn (57), and Cody (57).  The lowest number of species (15) was recorded at the Gillette CBC, followed by Green River (30), Cheyenne (31), and Sundance (33).  The greatest number of individual birds was recorded at Casper (13,609), Riverton (7536), Sheridan (6989), and Guernsey-Fort Laramie (5987), while the fewest were recorded at Sundance (1316), Cheyenne (1763), and Dubois (1921). Species with the highest combined counts were European Starling (14,847), House Sparrow (12,124), Canada Goose (9214), Mallard (6493), Bohemian Waxwing (4723), and Rock Pigeon (4199). The large number of Bohemian Waxwings was due primarily to a single flock of 2800 seen during the Pinedale CBC!

Unusual species for the state or circle requiring documentation included Rusty Blackbird at both Albany County and Dubois, an American Black Duck x Mallard hybrid at Bates Hole, Purple Finch at Casper, Merlin at Crowheart, Trumpeter Swan at Evanston, Swamp Sparrow at Lander, and Juniper Titmouse at Riverton.

Twenty-five species occurred only on one count, while only two species (Eurasian Collared-Dove and House Sparrow) were recorded on all 20 CBC circles.   Several species that typically migrate south lingered through the early winter; the most notable of these were Cinnamon Teal, Western Kingbird, and Spotted Towhee. Weather was rather mild for those counts conducted early and late in the count period, with high temperatures in the 40s in some locations, while much colder temperatures and snow occurred towards the middle of the count period.

By Wyoming standards, the number of participants for the 120th CBC was very high, with 387 participants in the field and 109 feeder watchers statewide.  Jackson Hole had the highest number of participants in the field, with 58, followed by Casper (35), Sheridan (32), and Story-Bighorn (31). However, kudos also is due to the five participants who managed to cover the Green River and Cheyenne CBC circles.  The greatest age range likely occurred in Casper, where participants ranged in age from nine to 95!

I would like to thank everyone who participated in the 120th CBC in Wyoming, as well as the compilers and observers for submitting rare bird documentation forms for the unusual birds observed during Wyoming CBCs this year. On one final note, Wyoming is expected to add another CBC circle beginning with a test run during the 121st CBC.  It will be called the Goshen Hole CBC in Goshen County. This is a major wintering area for waterfowl, eagles and other birds, and will be an interesting addition to Wyoming’s CBC data.