A total of 51 Christmas Bird Counts was submitted to the Christmas Bird Count Website by the end of February deadline from Colorado this past winter (December 14, 2019-January 5, 2020). Two new counts were started; Aaron Shipe started the North JeffCo count, which is north of Denver and south of Boulder, in Northern Jefferson County. A lot of birders in this circle helped find over 100 species this year. Gary Lefko started the new Pawnee National Grasslands – East count in Weld County, this count found 3228 Horned Larks, which was 95.8% of the birds counted on this count.
As usual the weather always plays factors for CBCs in Colorado. Some mountain counts and others reported snow on count day, and also wind can make birds hard to find on census day as well. Additionally, counts with open water can boost their species tallies. In all, 201 species of birds were found on count day, and the only additional count week species found was White-tailed Ptarmigan at Aspen. Mark Yaeger’s Pueblo Reservoir count found the most species with 132 on count day, which is the 2nd highest count total ever for Colorado (Penrose reached 134 a couple of years ago). The weather conditions were nearly perfect on count day, enabling the observers to find many species. Other counts tallying over 100 species were Penrose (110), Grand Junction and Boulder (108), the new North JeffCo count (106), Pueblo (103), and Denver (101). The Crook CBC in North East Colorado counted the most birds with 114,110, and 74.5 % of birds counted on this count were Snow Geese.
Only three Colorado Bird Records Committee review species were found. A Gyrfalcon appeared for the 2nd year in a row on the Loveland CBC on 1 January. A Brant (Black) was found on the new North JeffCo CBC on 20 December. Photos of a Pacific Wren were submitted from the Colorado Springs CBC on 14 Dec, and audio was submitted for another Pacific Wren on the Penrose CBC on Dec 22.
Here are some of the other highlights: A large flock for Colorado, 312 Greater White-fronted Geese were at Weldona-Fort Morgan. Trumpeter Swans were found on a few counts, two at Crook, two at Denver, two at Evergreen-Idaho Springs, were considered wild birds, while nine at Roaring Fork River Valley were considered feral and not countable birds. Four Tundra Swans were at Boulder, and this species was also found during count week at Denver. Rare in winter, two Blue-winged Teal were at Fort Collins. There were 21 Greater Scaup found, including one at Eagle Valley, which was unusual. The only scoter was a White-winged at Denver. Six Long-tailed Ducks were found, including one at Grand Junction in western Colorado. Statewide 206 Barrow’s Goldeneyes were tallied.
More loons were reported this past winter, with single Red-throated Loons found at both Pueblo Reservoir and Pueblo; four Pacific Loons were tallied, with two at Pueblo Reservoir, one each at Denver and North JeffCo; and five Common Loons were found as well. Two Red-necked Grebes were at Pueblo Reservoir. A large flock of 46 American White Pelicans graced Barr Lake, and three each were found at Denver (Urban) and John Martin Reservoir.
An injured Turkey Vulture was seen at Hotchkiss, and an Osprey was found at Grand Junction, both unexpected on Colorado CBCs. The marshes in Colorado hosted a good number of rails this winter; 105 Virginia Rails and five Sora were tallied. West Slope CBCs had the only Sandhill Cranes, at Montrose, Delta, Grand Junction, and Cortez.
The 120th CBC was a better winter for odd shorebirds, with two Spotted Sandpipers at Hotchkiss, three Greater Yellowlegs at Monte Vista N.W.R., a Dunlin at Rocky Ford, and Least Sandpipers at Denver, Longmont, and Pueblo Reservoir (two).
Ten species of gulls were reported this winter. Included were: 369 Bonaparte’s; a very unexpected dark-headed gull, either Laughing or Franklin’s at Colorado Springs; two Mew at Pueblo Reservoir; 19 Iceland (Thayer’s); 21 Lesser Black-backed; five Glaucous; and the usual Great Black-backed at Pueblo Reservoir.
Remember when White-winged Doves were rare in Colorado in the 1990s? There are lots of them now on Colorado CBCs, with 253 counted this winter. Seven Greater Roadrunners were also found.
Owl totals included: six Barn; 84 Western Screech; 25 Eastern Screech; 318 Great Horned; nine Northern Pygmy; 12 Long-eared; two Short-eared; and 13 Northern Saw-whet.
A Lewis’s Woodpecker was found for the first time on the Rocky Mountain N.P. count. Rare in winter, three Red-headed Woodpeckers were found at Sterling. Crook and Sterling found Red-bellied Woodpeckers. Williamson’s Sapsuckers winter in small numbers in Colorado, and a few CBCs found them, with four at Penrose, one at North JeffCo, one at Roaring Fork River Valley, and count week at Lake Isabel. Five Yellow-bellied Sapsuckers were found, four on Northern Front Range counts (Boulder, Denver, Fort Collins, North JeffCo), and one in western Colorado at Roaring Fork River Valley. A Red-naped Sapsucker was at Grand Junction. Four Ladder-backed Woodpeckers and eight American Three-toed Woodpeckers were tallied.
Three Peregrine Falcons were found (Grand Junction, Grand Mesa, and Monte Vista N.W.R.).
It was a big winter for phoebes—the 11 Black Phoebes and 33 Say’s Phoebes were more than usual. Very north of usual range, three Chihuahuan Ravens were detected at Boulder. A Tree Swallow was at Grand Junction. A House Wren was well photographed at Fountain Creek. Only two Winter Wrens were found, one at John Martin Reservoir and one at Penrose (near the Pacific Wren). A Carolina Wren was at Pueblo Reservoir. Delta, Hotchkiss, and Grand Junction tallied Blue-gray Gnatcatchers. Six Hermit Thrushes were found, and one Varied Thrush was at Denver. Five Gray Catbirds, two Brown Thrashers, three Sage Thrashers, and one Northern Mockingbird were found.
No eastern warblers were found on any counts. Two Common Yellowthroats (North JeffCo and Pueblo Reservoir); a Yellow Warbler (at Pueblo Reservoir); and two Wilson’s Warblers (Boulder and Grand Junction) were all of note for winter.
There are interesting sparrows around each winter. Single Chipping Sparrows were tallied at Durango and Pueblo Reservoir. A very rare Lark Sparrow was found at John Martin Reservoir. There were 14 Harris’s Sparrows tallied, including one in south west Colorado at Cortez and count week at Fairplay, and a total of 16 White-throated Sparrows (Montrose and Grand Junction in western found one each). A Savannah Sparrow was at John Martin Reservoir. There were 17 Lincoln’s Sparrows and 20 Swamp Sparrows. Three counts found Rufous-crowned Sparrows (John Martin Reservoir, Penrose, and Pinyon Canyon).
Nine Northern Cardinals were tallied, one in Boulder was the most unusual. Nine Rusty Blackbirds were seen, including four on the Roaring Fork River Valley count. Only 13 Common Grackles were found, plus 20 Brown-headed Cowbirds. It seemed to be a good winter for Red Crossbills on CBCs, there were 2054 counted, including two at Pinon Canyon, which was unusual there. Lesser Goldfinches seem to be possible on many counts nowadays, with 135 counted statewide. There 646 Evening Grosbeaks around the state, a good total.
Thanks to the all the compilers and participants for making this another successful Christmas Bird Count Season.