The 122nd Christmas Bird Count in Wyoming

Despite the continuing challenges associated with Covid 19, 18 of Wyoming’s 20 CBCs were conducted for the 122nd Christmas Bird Count, and 87,823 birds of 119 species were recorded. The number of species typically ranges from 110 to 133, so CBC-122 was in the middle of the spectrum.  

Kane had the highest number of species (66), followed by Casper (65), Buffalo and Lander (57 each), and Riverton (50).  The lowest number of species (31) was recorded at the Green River CBC.  The greatest number of individual birds was recorded at Riverton (17,089), Casper (12,674), and Kane (9,080), while the fewest were recorded at Sundance (1422), Cody (1896) and Jackson Hole (1909). Species with the highest combined counts included Canada Goose (17,568), European Starling (9209), House Sparrow (9116), Rock Pigeon (8169), Mallard (7284), and American Crow (5838).  Introduced invasive species (House Sparrow, European Starling, Rock Pigeon, Eurasian Collared-Dove), accounted for 35% of all birds seen, which is remarkable for a rural state like Wyoming.

Unusual birds observed during the 122nd CBC included Red-breasted Merganser and Fox Sparrow at Buffalo, Gyrfalcon at Casper, Northern Goshawk and Sandhill Crane at Evanston, Spotted Towhee and Hoary Redpoll at Lander, and Snow Goose and Cackling Goose at Riverton. Twenty-five species occurred only on one count, while five species were recorded on all 18 CBC circles, including Mallard, Bald Eagle, Black-billed Magpie, European Starling, and House Sparrow.  Several other species not commonly seen in Wyoming in winter included Greater White-fronted Goose, Snow Goose, Wood Duck, Pied-billed Grebe, Loggerhead Shrike, Marsh Wren, Fox Sparrow, Common Grackle, and Lesser Goldfinch. 

There has lately been much concern in the local Wyoming press over the status of Golden Eagles in Wyoming, especially given the recent expansion of wind energy development in the state, so I was curious to see the trend in wintering Golden Eagle populations in Wyoming based on CBC data.  Over the last 20 years, although this is not a rigorous statistical analysis, it appears that Golden Eagle populations have remained fairly steady, with counts over the last two years similar to those observed 15-20 years ago. In contrast, as is occurring throughout the rest of North America, the number of wintering Bald Eagles in Wyoming appears to have substantially increased over the last 20 years.

The number of participants for the 122nd CBC was somewhat below last year, but still relatively high, even with Covid 19 and two CBC circles not conducted.  A total of 346 field counters and 76 feeder counters participated in the 122nd CBC. The largest turnout was in Jackson Hole, with 57 field counters. Other counts with high field observer turnouts (by Wyoming standards) were Casper (30), Dubois (26), and Pinedale (23).  However, kudos also is due to the five participants who managed to cover the Guernsey-Fort Laramie CBC circle.  Wyoming CBC observers covered 238 miles on foot, 3792 miles by car, 47 miles by ATV, eight miles by bicycle, and 30 miles on skis. I would like to thank everyone who participated in the 122nd CBC in Wyoming, as well as the compilers and observers for submitting rare bird documentation forms for the unusual birds observed on Wyoming CBCs this year.