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The 117th CBC in Colorado
Conditions in the 117th CBC:
Weather conditions are always a factor for Colorado Christmas Bird Counts. This year it made things a challenge for many counts on the first weekend of December 17-18. Counts held on December 14th and 15th got lucky with the warm weather, and then windy on the 16th, before a major arctic cold front and snow event occurred during the night of December 16-17, making some counts very difficult for observers and birds on the 17th. The weather was still cold on Sunday the 18th as well. Most Colorado CBCs are held over the first weekend, so some counts didn’t have as many observers, or as many bird species as usual, though other counts did quite well that weekend, especially in northern Colorado. Counts held later in the season, seemed to not have as many weather issues, except for wind on some counts.
John Martin Reservoir in SE Colorado was lucky with the weather conditions on December 15th, and found an amazing total of 117 species on count day! Other counts with high totals of species were: Denver (112 species), Penrose (111 species), Boulder (109 species), Loveland (105 species), and Pueblo Reservoir (102 species, which was lower than usual, by 20 some species). The new Air Force Academy CBC in northern El Paso County found 44 species. Both Dotsero and Summit County counts were held this year, after a hiatus.
A total of 206 species of birds was found on the 50 Colorado CBCs that were submitted this season, which is good. While some counts had fewer species than normal, many counts had more than usual.
A total of 934,286 birds were counted on Colorado CBCs. An amazing number were geese (478,776 of them), which is 51.2 % of the birds counted!
Highlights:
The most exciting bird seen on a Colorado CBC this year, was without a doubt, Colorado’s first state record of Purple Sandpiper. The bird was found and identified correctly by teen-age birders from Boulder County, Jack and Ryan Bushong on 16 December 2016, in the mountains of Summit County after a day of sking. The bird was viewed by hundreds of birders through 31 December 2016, including on the Summit County CBC on 26 December 2016!
Other Colorado Bird Records Committee state review species that were found this season on Colorado CBCs were Eurasian Wigeon (Penrose) and Iceland Gull (Loveland). There were several out of season species as well, which will be highlighted below.
As mentioned above, geese were everywhere – 41 Greater White-fronted, 227,628 Snow, 24,032 Ross’s, 74,235 Cackling, 141,492 Canada, and 11,348 Cackling/Canada. Greeley found the only feral Mute Swan this year; this species does not appear on the official Colorado state list, so it isn’t counted in the total number of species. Resident Trumpeter Swans were seen on both Pagosa Springs and Roaring Fork River Valley counts, and were also marked as feral (not countable birds). Fountain Creek found two Trumpeter Swans as well as a Tundra Swan. Tundra Swans were also found at Boulder (4), Delta (14), Rawhide Energy Station (5), Salida (2), and Monte Vista (count week). A Mallard (Mexican intergrade) was at Pueblo Reservoir count week. Good details were provided for a Blue-winged Teal (rare in winter) on the Great Sand Dunes N.P. count. A much unexpected Surf Scoter was found on the Spanish Peaks count, and a Black Scoter was at Denver. Single Long-tailed Ducks were found at Denver, Loveland, Rawhide Energy Station, and Salida.
It is usually a challenge to find grouse and prairie-chicken in the winter, so it is always noteworthy when they are found. This year’s list included: four Greater Sage-Grouse at North Park, two Dusky Grouse and four Sharp-tailed Grouse at Steamboat Springs, and Greater Prairie-Chickens at Bonny Reservoir (59) and Sterling (12).
Loons are usually only possible on few counts in Colorado. A Pacific Loon was at John Martin Reservoir and Common Loons were at Denver (1), Durango (1), John Martin Reservoir (4), Loveland (1), and Pueblo Reservoir (1). Only two counts found Horned Grebes, four at Pueblo Reservoir and six at Rawhide Energy Station. The rarest of the grebes in Colorado, single Red-necked Grebes were found at Boulder and Pueblo Reservoir. A Clark’s Grebe was at John Martin Reservoir, as well as two Western x Clark’s Grebe (hybrids). American White Pelicans winter in low numbers in Colorado; this year’s counts found one at Greeley, one at Rawhide Energy Station, one at Rocky Ford, and count week at John Martin Reservoir. A much unexpected count week American Bittern was reported from Monte Vista N.W.R. Black-crowned Night-Herons were found on the usual counts, Boulder (2) and Denver (Urban) (7).
A count week Turkey Vulture was described reasonable well at Douglas County. Soras were only found at John Martin Reservoir (4) and Pueblo (1). Sandhill Cranes continue to winter in good numbers at couple of west slope locations Delta (1814) and Montrose (779), and one was out of place in NE Colorado at Crook. Shorebirds other than Killdeer and Wilson’s Snipe are quite rare in Colorado in winter. Single Spotted Sandpipers were found at Grand Junction and Pueblo Reservoir. Both Barr Lake (1) and Grand Junction (2) found Greater Yellowlegs. A Dunlin was found at Denver, and photographed.
Colorado is always a good place for wintering gulls. Christmas Bird Counts seem to find some rarer ones each year. Bonaparte’s Gulls were at John Martin Reservoir (5) and Pueblo Reservoir (86) – even though the steam and fog covered the lake the entire day. One wonders how many really were out there, since on 1 Jan 2017, there were over 200! A count week Bonaparte’s was up north at Fort Collins. From the west coast, single Mew Gulls (all adults) turned up at Denver (Urban), Loveland, and Pueblo Reservoir, as well as a count week at Fort Collins. Thayer’s Gulls showed up on four counts, one at Fountain Creek, four at John Martin Reservoir, six at Loveland, and one at Pueblo Reservoir. Lesser Black-backed Gulls also were found on four counts, Boulder (2), John Martin Reservoir (4), Loveland (5), and Pueblo Reservoir (4). From the north, a Glaucous Gull was found in SE Colorado at John Martin Reservoir. Singe Great Black-backed Gulls were at John Martin Reservoir, Loveland, and Pueblo Reservoir.
Greater Roadrunners are hard to find, usually only on a few counts in southern Colorado. An amazing 13 roadrunners were found at John Martin Reservoir, plus singles at Penrose, Pueblo Reservoir (running in front of birders on the snow!), and Rocky Ford.
Owl totals this season are as follows: eight Barns, 80 Western Screech, 38 Eastern Screech, 296 Great Horned, six Northern Pygmy, 16 Long-eared, three Short-eared, a Boreal (at Grand Mesa), and six Northern Saw-whet.
An Acorn Woodpecker was found at a usual location on the Lake Isabel count. Sapsucker reports this season were three Williamson’s (all at Penrose), four Yellow-bellied (singles at Bonny Reservoir, Lake Isabel, Penrose, and Pueblo Reservoir, also count week at Colorado Springs), and Red-naped (three at Cortez, one at Grand Junction, and count week at Durango). Single American Three-toed Woodpeckers were only found at Rocky Mountain N.P. and Summit County.
Peregrine Falcons were found at Grand Junction (1), Montrose (2), and count week at Colorado Springs.
Phoebes are the only regular flycatchers in Colorado in winter. Black Phoebes were found at Penrose (3), single Eastern Phoebes were found count day at Boulder and count week at Denver, and nine counts found Say’s Phoebes, with a total of 14 found.
Colorado birders are keeping track of White-breasted Nuthatch sub-species on Christmas Bird Counts. In total 765 (Interior West) were counted, 27 (Eastern), and six not identified to sub-species from places where either one is possible.
Single Winter Wrens were found at Fountain Creek, Lake Isabel, and count week at Pueblo Reservoir. Winter/Pacific Wrens were also at Denver (Urban) and Fort Collins. No certain Pacific Wrens were reported. A Carolina Wren was at Bonny Reservoir, and count week at Pueblo Reservoir. Both Hotchkiss and John Martin Reservoir found single Blue-gray Gnatcatchers.
Bluebirds weren’t seen in great numbers this winter -- 166 Eastern, 154 Western, and only 1808 Mountain. Also, a low number of Hermit Thrushes, one at Pueblo Reservoir and one at Rocky Ford, also count week at Denver and Durango. Forty-seven of the 50 counts in Colorado found American Robins, which several people mentioned they had in larger numbers than usual. The state wide total was 20,631 American Robins! With all those robins, there ought to a Varied Thrush somewhere, and there was one at Sterling in NE Colorado! Gray Catbirds were only found on three counts, singles at Boulder, Fort Collins, and Rocky Ford. Brown Thrashers were found on three counts, Denver, Douglas County, and Monte Vista N.W.R. all singles, plus count week at Bonny Reservoir. Single Sage Thrashers were at Fountain Creek and Penrose. The only Northern Mockingbirds were singles at Boulder, Pagosa Springs, and Rocky Ford. Steamboat Springs again found most of the Bohemian Waxwings in Colorado, with 398 of them, and Boulder found four.
Flagler found 373 Lapland Longspurs on count day in nice weather, though the next day in snowy weather there were 500,000! Flagler also found the only Chestnut-collared Longspur.
A few interesting warblers were found. An Ovenbird was nicely photographed from John Martin Reservoir in SE Colorado. An Orange-crowned Warbler was at Grand Junction in western Colorado. A Common Yellowthroat was photographed three days before the Pueblo Reservoir CBC for count week, though could not be found in the snowing cold weather on count day.
Totally unexpected was a Grasshopper Sparrow photographed in the snowy weather at Denver! Fox Sparrow (Slate-colored) was at Durango (one) and Montrose (two). A Golden-crowned Sparrow was photographed in SE Colorado at Rocky Ford. Twenty Harris’s Sparrows and nine White-throated Sparrows were found. An unexpected Savannah Sparrow was at Boulder. Only five Lincoln’s and 11 Swamp Sparrows were found. As usual the only Rufous-crowned Sparrow was at Penrose, as was a Green-tailed Towhee, where much less expected there.
Five counts found a total of 22 Northern Cardinals, all on eastern plains counts, none along the Front Range to the west. A Rose-breasted Grosbeak was photographed at Fort Collins, which was a surprise. Yellow-headed Blackbirds were found on five counts. Not a lot of Rusty Blackbirds turned up; four at Barr Lake, one at Pueblo Reservoir, two at Spanish Peaks, and count week at Fort Collins. Another bird that shouldn’t be in Colorado in winter, a Bullock’s Oriole was photographed at Boulder. Rosy-finches were found in a little bit better numbers this year. A total of 2129 rosy-finches, 496 Gray-crowned (some of these are also Hepburn’s, most compiler don’t separate them), three Hepburn’s Gray-crowned, 40 Black, 1346 Brown-capped, and 244 unknown ones were found. Granby reported 26 Common Redpolls, no other counts found any. Only 413 Pine Siskins and 373 Evening Grosbeaks were counted statewide, low numbers for both.
Thanks to all the compilers, counters, and landowners who let people count birds on their properties for Colorado Christmas Bird Counts.