Rare for the West Slope, two reports of Greater White-fronted Goose were noteworthy: one at Confluence Park, Delta from 9 -16 Dec (R. Harner, M. Briggs) and one in Parachute, Garfield 17 Feb (VZ). Brant (Black) is typically found in small numbers within the state. Continuing this trend was one at Hidden (Mayham) Lake, Adams 13–19 Dec (CR), one at Aurora Res., Arapahoe 23 Dec -24 Jan (MR, m.ob.), one at East Lake Shores Park, Adams 31 Dec (KM), and one at Indian Tree Golf Course, Jefferson 26 Jan+ (DF, m.ob.). Trumpeter Swan numbers were up the week of 1 Jan with totals of 33, higher than any of the previous five years. Reports were spread out across nine counties from the West Slope to the northeast and south to the Colorado Springs area from 14 Dec–12 Feb. There were also many Tundra Swan reports, from 15 counties from 1 Dec -14 Feb. Always a nice find, two different Eurasian Wigeon reports were of interest, one from Cañon City, Fremont 7-18 Dec (MP, m.ob.) and another at Verhoeff Res. Bent 12 Feb (JWT). With less than ten winter records dating back to 1950, two American Black Duck sightings in one season were noteworthy: one at Poudre Ponds, Weld 4 Dec (SGM, NM) and another at Woods Lake, Weld 25–27 Feb (SGM). A Blue-winged Teal was found at Verhoeff Res., Bent 12 Feb (JS, JWT) and another at Belmar Park, Jefferson 28 Feb (AH, MC). Surf Scoter was present in Adams, Arapahoe, Huerfano, and Weld from 2–31 Dec; as many as three continued from Aurora Res., Arapahoe 26 Oct (DD, m.ob.). White-winged Scoter also continued from the previous season, and well into February, with as many as three at Aurora Res., Arapahoe from 2 Dec–12 Feb (DD, m.ob.). Black Scoter was found in three locations: one ongoing from 15 Nov at Aurora Res., Arapahoe, 2 Dec (DD), the high count of the season of three at Adobe Creek Res., Bent 3 Dec (DD), and another at South Platte Res, Arapahoe from 11-26 Nov (SS, m.ob.). Long-tailed Duck reports were numerous, with birds found in the counties of Adams, Arapahoe, Bent, Chaffee, Douglas, Jefferson, Larimer, Pueblo, and Routt from 23 Nov – 20 Jan (m.ob.) A Bufflehead x Common Goldeneye (hybrid) was noted in Craig, Moffat 10 Feb (JL).
Grebes through Shorebirds
Red-necked Grebes were found at four locations: one at Boulder Res., Boulder from 28 Oct – 6 Dec (DD, m.ob.), one at Pueblo Res., Pueblo from 30 Oct -28 Feb, two at the same location from 2 – 22 Jan (BKP), one at Valmont Res. Boulder from 3 Dec – 13 Jan (JP, m.ob.), and one at Walden Ponds, Boulder 9 Jan (KM). With no prior winter records in western Colorado to date, a Clark’s Grebe at Navajo Res., Archuleta 22 Feb (JB) was a surprise. A lone Band-tailed Pigeon at Green Mountain Falls, Teller from 15–17 Jan (RB, JA) was the only of its kind for the season. As many as three White-throated Swifts were near Cañon City, Fremont from 30 Dec – 1 Jan (D. Belter et al.). A rare winter visitor, Dunlin, was found in three different locations, making it a good year for the species. One was at Cherry Creek S.P., Arapahoe 7 Dec (AH, MC, m.ob.), another at McLellan Res., Arapahoe 17 Dec (E. Holub, T. Holub), and reported again at the same location from 24 Jan – 14 Feb, (GG, m.ob.), and another at Pueblo Res., Pueblo from 21 Jan – 5 Feb (JC, RC, m.ob.). A first state record Purple Sandpiper was discovered at the unlikely location of Dillon Res., Summit from 16-31 Dec (RB, JB, m.ob.). Many birders from all around the state trekked through the deep snow to view the bird in the Colorado high country. Rare for winter, a Baird’s Sandpiper was found at John Martin Res., Bent 26 Feb (D. Nelson). Least Sandpiper is equally rare at this time of year, so two at Rocky Ford S.W.A., Otero 30 Jan (S. Oswald) were of interest. Continuing the shorebird in winter trend, two Long-billed Dowitchers were seen at Boyd Lake, Larimer 20 Feb (M. McCloy, A. Bankert). A second report of two at Pueblo Chemical Depot, Pueblo 22 Feb (C. Jones) was of interest. For the third year in a row, American Woodcock was present at Bobcat Ridge N.A., Larimer, with up to two 8-11 Jan, and then one 13 Jan–28 Feb (D. Wade, C. Wild, m.ob.). Spotted Sandpiper was found at ten different locations in Adams, Arapahoe, Archuleta, Douglas, Garfield, La Plata, Mesa, and Pueblo from 2 Dec – 18 Feb (m.ob.).
Gulls Through Flycatchers
A rare winter Franklin’s Gull at Horsetooth Res., Larimer 14 Jan (NK) was just the fourth winter record, dating back to 2000, and the first of its kind since 2011. Rare for the date and location was a California Gull at Ridgway Res., Ouray 11 Jan (KMD). Iceland Gull was prevalent, with eBird tallying an impressive 134 the week beginning 15 Jan. This species has steadily increased in numbers year by year since the first sighting back in 1999, and is expected now with an increased degree of frequency. With 16 records since 2009 and 32 accepted records overall (43 in eBird), Glaucous-winged Gull can usually be found in very small numbers. This season three were found: a first-cycle bird at Larimer County Landfill, Larimer 30 (DD) and two first-cycle birds at Aurora Res., Arapahoe 15–28 Jan (SW, SGM, m.ob.). Great Black-backed Gull has also increased its frequency in the state in the last five years. Six reports from the four counties of Arapahoe, Boulder, Larimer, and Pueblo were good, with eBird tallying an impressive 24 the week of 22 Jan. This is a record high total to date.
Rare for the date, location, and elevation was a Barn Owl near Ridgway, Ouray 21 Dec (KN). Red-naped Sapsucker was found in the four counties of Boulder, Fremont, Mesa, and La Plata from 14 Dec -13 Feb. Most reports are usually single birds, making the report of two near Durango, La Plata 14 Dec–7 Jan, (RV, KD) notable. A surprise for the Boulder Christmas bird count, was the 2nd Eastern Phoebe found in its 75th year of reporting. The bird appeared pure with no signs of Black Phoebe genes; found at White Rocks Trail area, Boulder 18 Dec (CN, PG). Another was found at South Platte Park, Arapahoe 18 Dec (BS) and again 19 Feb (DW). A state first for the season was a Western Kingbird at Cherry Creek S.P., Arapahoe 25 Feb (SR, WW).
Wrens Through Blackbirds
One of just five winter records of the species, a Pacific Wren in Durango, La Plata 19 Jan – 8 Feb (RV, m.ob.) was a great find. Becoming more regular in the state, two reports of Carolina Wren were good, one found in Colorado Springs, El Paso 6 Dec (JR) and one in Lamar, Prowers 17 Jan – 19 Feb (ph. DL, m.ob.). With only three previous winter records to date, multiple reports throughout the state of Blue-gray Gnatcatcher were of interest. One at John Martin Res., Bent 15 Dec (MP, BS), one in Hotchkiss, Delta 1 Jan (DG), two at Pueblo Res., Pueblo 18 Jan (PS, CH), and two at Brewster’s Ridge, Mesa 21 Feb (DV, MV) made it a banner year for the species. Varied Thrush made two appearances; one near Sterling, Logan 20 Dec–2 Jan (WK, m.ob.) and another at Ken Caryl Valley, Jefferson 29 Dec (DS). A small population of Curve-billed Thrasher has been known to be breeding on private property near the Pawnee Grasslands area in northeast Weld County for years now. One was photographed at this location this season on 30 Jan (ph. DL). Far north from their typical breeding locations, this unique habitat of cholla cactus mixed with coniferous and deciduous trees, continues to support this small population of Curve-billed Thrashers. Typically, a good location for Bohemian Waxwings, Steamboat Springs proved that point again with 200-400 in the area including 120 at one location Routt 14-17 Dec (TM et al.). Other reports included one in Boulder, Boulder 19 Dec (MC), 22 in Allenspark, Larimer 28 Dec (CW, JB), and one at Rocky Mountain N.P. Larimer 1 Jan (SW). White-winged Crossbill was noted twice, with one at Left Hand Res., Boulder 15 Jan (CN) and 12 at Winter Park Ski Area, Grand 12 Feb (AB).
The mild winter weather this year might explain the diverse sparrow sightings. A Chipping Sparrow was found near Franktown, Douglas 6 Dec (HK), a Lark Sparrow at Parker Regional Park, Douglas 3 Dec (CG), a Savannah Sparrow near Boulder, Boulder 18 Dec and 24 Feb (CN, PG), a Grasshopper Sparrow at Chatfield S.P., Douglas/Jefferson 17 Dec (JK), and a Fox Sparrow (Red) in Colorado Springs, El Paso 27 Feb (RT, DT). Along with these sightings, Harris’s Sparrow was reported throughout the Front Range and on the eastern plains. One in Craig, Moffat 4-25 Jan (JL) and one in the town of Jefferson, Park 5-28 Jan (JWC, m.ob.) were of interest. The rarest of the Sparrow reports were two Golden-crowned Sparrows: one near Grand Junction, Mesa 6 Dec–8 Jan (CO, m.ob.) and one at Rocky Ford S.W.A., Otero 16 Dec (KMD). Eastern Meadowlark (Lilian’s) is rare at any time in the state, so the one found at John Martin Res., Bent 5 Feb (SGM, DD) was of interest. Also, of note was a rare winter Bullock’s Oriole in Boulder, Boulder 13-18 Dec (LO, m.ob.). Rusty Blackbird was noted throughout the state in five counties from 26 Nov–10 Feb (m.ob.).
Acknowledgements: Many thanks to David Dowell for his central role in compiling sightings for the Colorado Birds Journal.
Report processed by Byron Swift, 2 Mar 2021.