Colorado: Winter 2020–2021

Winter 2020–2021: 1 Dec–28 Feb

Dean Shoup      

Recommended citation:

Shoup, D. 2021. Winter 2020–2021: Colorado. <> North American Birds.

Colorado winter weather was mostly mild for 2020-2021 until February. From 12 Feb through the 16th, temperatures dropped significantly to zero Fahrenheit or lower. On the 14th, the high was 1 degree above zero and the low was 14 degrees below zero, both record values for the day. Denver also had some higher-than-average precipitation, getting 13.5 inches of snow. This was 7.8 inches higher than the normal 5.7 inches for the month. The 9.6 inches of snow the city saw from the 24th through the 25th was the greatest snowfall for the season in the Denver area. 

This winter season in Colorado was highlighted by a returning Gyrfalcon in the Fort Collins area, multiple groups of Bohemian Waxwings in the Steamboat Springs area, and a number of Purple Finches throughout the state. A lone Snowy Owl was good for the season along with a Boreal Owl that pleasantly surprised birders near the town of Louviers. It was a great year for regular-but-rare gulls including many sightings of Glaucous-winged Gull, Glaucous Gull, and rarely reported hybrids such as Laughing x Ring-billed Gull and Herring x Lesser Black-backed Gull. Two different reports of Red-naped x Red-breasted Sapsucker were also of interest. Common Redpolls and Snow Buntings were more prevalent this year than in recent years past as well. Other rarities included a Canyon Towhee in Larimer Co; an Eastern Towhee in Logan Co; a Black-throated Blue Warbler in Pueblo Co; multiple reports of Palm and Pine warblers; and a long-staying Summer Tanager in the Denver area.

Sub-regional Compilers: Coen Dexter (western Colorado including northwest, west-central, and southwest regions).

Waterfowl through Waxwings

A Brant at Bowles Grove Park, Arapahoe Co 2 Dec (Linda P.) was the only of its kind for the season. A Eurasian Wigeon was found at Cañon City—Valco Pond, Fremont Co, 24 – 27 Feb (Mark Peterson et al.). White-winged Scoters were found in four counties with no more than two at any one location from 3 Dec–6 Jan (Dale Pate, m.ob.). Black Scoters were also seen in just four counties with a high count of three at Marston Reservoir, Denver Co 23–15 Dec (Norm Erthal, m.ob.). Long-tailed Ducks had an impressive showing in 12 counties from 1 Dec–28 Feb (m.ob.). Dunlin were present in five locations in four counties with no more than two at any one location from 7 Dec–8 Feb (William Kelley, m.ob.). Least Sandpipers were observed in Mesa, Pueblo, and Weld Cos from 5 Dec – 24 Feb (David Price, m.ob.). Rare for the state and even rarer for the county, a Black-legged Kittiwake was at Lathrop SP, Huerfano Co 12 Dec (Kathy Mihm Dunning). A Laughing x Ring-billed Gull (hybrid) was documented at McIntosh Lake, Boulder Co 21 Jan (David Dowell). Thayer’s Iceland Gulls have become common in Colorado—less common are Kumlien’s Iceland Gull. Kumlien’s Iceland Gull were observed at seven locations in Arapahoe, Bent, Kiowa, and Larimer Cos from 17 Dec–3 Feb (Steven Mlodinow et al.). A Herring x Lesser Black-backed Gull (hybrid) was of interest at Warren Lake, Larimer Co 17 Jan (Nick Komar, Scott Rashid). Glaucous-winged Gull sightings are on the rise in Colorado with seven observed in Arapahoe, Bent, Kiowa, and Larimer Cos from 4 Dec–7 Feb (Steven Mlodinow et al.). Four Herring x Glaucous-winged Gull (hybrid) sightings were good for the season in Arapahoe and Larimer Cos from 22 Dec–27 Feb (Steven Mlodinow, David Dowell, et al.). Glaucous Gull reports were high for the season with reports from 12 locations in six counties including one along the South Platte River, Adams Co 9 Feb (ph. Adam Vesely). One Herring x Glaucous Gull (hybrid) was documented at John Martin Reservoir, Bent Co 2 Jan (Steven Mlodinow, Mark Peterson). In addition to the regularly returning Great Black-backed Gull seen in Pueblo Co, three more were observed in Arapahoe, Bent, and Boulder Cos from 22 Nov–10 Jan (David Tønnessen, Steven Mlodinow, Leslie S.). 

A Red-throated Loon at Pueblo Reservoir, Pueblo Co 6 Dec–23 Jan was the only report for the season (Chris Knight, Brandon K. Percival). Two Pacific Loon reports came in from Boulder and Las Animas Cos from 26 Nov–12 Dec (Randall Siebert, Kathy Mihm Dunning). A Snowy Owl was a great find at Prowers CR S, Prowers Co 16 Jan (Nicole Rosmarino). Rare for the county was a Boreal Owl near the town of Louviers, Douglas Co 2–30 Jan (Thomas Halverstadt, m. ob.). Two reports of Red-naped x Red-breasted Sapsucker (hybrid) were of interest with one at Morrison Park, Jefferson Co 3–23 Jan (Burke Angstman) and one at Conquistador Golf Course, Montezuma Co, 7 Feb (Brenda Wright, Coen Dexter). A long staying Red-bellied Woodpecker was out of place at a private residence in Superior, Boulder Co 24 Nov–27 Feb (Jean Folsom, m. ob.). Returning for the third year in a row to the same location was a Gyrfalcon at Trilby Road and Taft Hill near the Larimer County Landfill, Larimer Co, 11 Dec (Nick Komar). Two Carolina Wrens were at Lamar Community College, Prowers Co 18 Dec–28 Feb (David Leatherman, m. ob.); another Carolina Wren was discovered at McIntosh Lake, Boulder Co 5 Feb (Bryan Guarente). A Wood Thrush was a good find at CF & I Lakes (restricted access), Pueblo Co 14 Dec (Mark Peterson). Six reports of Varied Thrush were good for the season in Boulder, Jefferson, La Plata, Montezuma, Prowers, and Weld Cos 23 Nov–28 Feb (Kelly Ormesher, m. ob.). Bohemian Waxwings were found in two areas with as many as 80 at one time in eight locations near Steamboat Springs, Routt Co 17 Dec–6 Feb (Tresa Moulton et al.) and two at Woodland Park, Teller Co 30 Dec (Richard Bunn, Jan Albright). 

Rosy-Finches through Tanagers

Gray-crowned Rosy-Finches had a good showing in 28 different counties from 1 Dec–28 Feb along with many reports of Black Rosy-Finch from 16 counties, 5 Dec–28 Feb (Rachel Hopper, m. ob.). Purple Finches were abundant this year with one at a farm yard in Prowers Co 1–2 Dec (Jane Stulp), one at South Mule Deer Drive, El Paso Co 11 Dec (Kip Miller), two at Purgatoire and Arkansas Confluence area, Bent Co 14 Dec (Kathy Mihm Dunning), one at Red Rock Canyon Open Space, El Paso Co 23–28 Jan (Jim Merritt), and three at Las Animas Junction, Bent Co 16 Feb (Steven Mlodinow). Common Redpolls were also exceptionally abundant this year with many reports of single birds from nine counties including Ouray Co, which is a review county for this species in the state, from 11 Dec–27 Feb (Don Marsh, Joey Kellner, m. ob.). Three reports of White-winged Crossbill were of interest with one at High Chaparral Open Space, El Paso Co 5 Dec (Terry Berger, Alan Ketcham), one at a private residence in Summit Co 21 Dec (Debbie Tyber), and one at Holbrook Park, Jefferson Co 28 Dec–7 Jan (m. ob.). 

Six reports of Snow Bunting were of interest, the rarest being one at Adobe Creek Res., Kiowa Co 4 Dec and one at Neegronda Res, Kiowa Co 11 Jan (Steven Mlodinow).  Black-throated Sparrows continue to be found in the winter months in areas that may have not previously been covered. Multiple birds were found in a variety of locations in the south-central part of the state with two at Higbee Cemetery, Otero Co 16 Jan (David Dowell); six at Higbee Valley Road, Otero Co 7 Feb (Joey Kellner), and four at Higbee Cemetery, Otero Co 4 Dec (Steven Mlodinow, Mark Peterson). Field Sparrows turned up with more frequency than in recent years with a total of 13 birds in seven locations within Baca, El Paso, Kiowa, Larimer, Otero, and Park Cos from 3 Dec–27 Jan (Doug Ward, m. ob.). Rare to the state, Golden-crowned Sparrow turned up in six locations, with reports from Boulder, Denver, Jefferson, Mesa, and Larimer Cos from 6 Dec–17 Feb (Mike Henwood, m. ob.). A Canyon Towhee was far north of its typical winter range and a first for Larimer Co in the winter months. One was at a private residence near Boedecker Lake, Larimer Co, 15 Dec–23 Feb (Greg Osland, m. ob.). An Eastern Towhee was at Prewitt Res., Logan Co, 23 Jan–28 Feb (David Dowell). As many as six Rusty Blackbirds were found in multiple locations in 13 counties, 1 Dec–28 Feb (m. ob.).

Northern Parula was found twice this season with one at Chatfield SP—below the dam, Douglas Co 28 Nov–26 Dec (Joey Kellner, m. ob.) and one at South Platte River—88th Ave area, Adams Co, 6–12 Dec (Burke Angstman). A Black-throated Blue Warbler was a great find in Pueblo City Park, Pueblo Co 1–2 Dec (Brandon K. Percival, Edward Landi). Two reports of Palm Warbler were good, with one from Bear Creek Lake Park, Jefferson Co 2–9 Dec (Reed Gorner, m. ob.) and one at South Platte River—Sand Creek mouth, Adams Co 22 Jan–6 Feb (Thaddeus Wells, m. ob.). Four reports of Pine Warbler were of interest in Douglas, Grand, Prowers, and Weld Cos from 7 Nov–27 Feb (Ned Wallace, Janet Rogers, Joey Negreann, Joey Kellner, Bill Pranther). Rare for the season was a Wilson’s Warbler at Baldridge and Ute Parks, Montrose Co 1 Dec (Bruce Ackerman et al.). A long staying Summer Tanager was first present in October at a private residence and continued through 28 Feb near Meadowbrook Park, Arapahoe Co 5–28 Feb (August Konvalin, m. ob.). A Western Tanager was found in Ouray, Ouray Co 23 Dec documented by the Biodiversity Initiative.

Report processed by Andrew Keaveney, 22 Oct 2021.

Photos–Colorado: Winter 2020–2021

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