| Acc. No. | Year | Location | County | Observers |
| 1908-003 | 1908 |
Trinidad
| Las Animas | Charles Aiken |
| 29-88-19 | 1987 |
Montrose
| Montrose | Mark Janos |
| 29-90-31 | 1990 |
Two Buttes State Wildlife Area
| Baca | Mark Janos |
| 29-91-39 | 1991 |
Clifton
| Mesa | Peter Gent, Vic Zerbi |
| 29-92-25 | 1992 |
Highline Lake State Park
| Mesa | Jack Reddall |
| 29-95-53 | 1995 |
Two Buttes State Wildlife Area
| Baca | Joe Mammoser |
| 29-95-54 | 1995 |
Poudre River Trail (Ft. Collins section)
| Larimer | Joe Mammoser |
| 29-95-55 | 1995 |
Two Buttes State Wildlife Area
| Baca | Jack Reddall |
| 1997-051 | 1995 |
Poudre River Trail (Ft. Collins section)
| Larimer | Dave Leatherman |
| 1997-052 | 1997 |
Lamar Community College
| Prowers | Dave Leatherman, David Quesenberry |
| 1997-053 | 1997 |
Lake Holbrook
| Otero | Mark Janos |
| 1997-054 | 1997 |
Poudre River Trail (Ft. Collins section)
| Larimer | Dave Leatherman |
| 1998-079 | 1998 |
Clifton
| Mesa | Paul Lehman |
| 1999-085 | 1999 |
Lamar Community College
| Prowers | Mark Janos |
| 2001-028 | 2001 |
Pueblo
| Pueblo | Randy Vernon |
| 2003-045 | 2003 |
Neenoshe Reservoir
| Kiowa | Ric Olson, Rachel Hopper |
| 2006-108 | 2006 |
Dove Creek
| Dolores | Andrew Spencer, Cole Wild |
| 2006-114 | 2006 |
Dove Creek
| Dolores | Jim Beatty |
| 2006-119 | 2006 |
Nucla
| Montrose | Andrew Spencer, Nathan Pieplow |
| 2008-075 | 2008 |
Chico Basin Ranch
| Pueblo | Bill Maynard, Brian Gibbons, Brandon Percival, Glenn Walbek |
| 2008-086 | 2008 |
Nucla
| Montrose | Andrew Spencer |
| 2010-079 | 2010 |
Mitchek Ranch near Flagler
| Cheyenne | Glenn Walbek |
| 2010-027 | 2010 |
Colorado City and Rye
| Pueblo | David Silverman |
| 2010-042 | 2010 |
Walden Ponds/Sawhill Ponds Complex
| Boulder | Al Guarente |
| 2011-002 | 2011 |
Nucla
| Montrose | Coen Dexter |
| 2011-108 | 2011 |
Nucla
| Montrose | Coen Dexter |
| 2013-178 | 2013 |
Blue Lake (Adobe Creek Reservoir)
| Kiowa | Steven Mlodinow |
| 2014-072 | 2014 |
Totten Reservoir
| Montezuma | Steven Mlodinow |
| 2014-129 | 2014 |
Nucla
| Montrose | Kathy Mihm Dunning, Mike Henwood, michael kiessig |
| 2016-016 | 2015 |
Nucla
| Montrose | Kathy Mihm Dunning |
| 2016-086 | 2016 |
Nucla
| Montrose | Coen Dexter |
| 2017-022 | 2017 |
Van's Grove
| Bent | Kathy Mihm Dunning |
| 2018-062 | 2018 |
Queens Reservoirs (Neeskah Reservoir area)
| Kiowa | Steven Mlodinow |
| 2019-036 | 2019 |
Van's Grove
| Bent | Brandon K. Percival, Tony Leukering |
| 2022-039 | 2022 |
Chico Basin Ranch
| Pueblo | Aaron Driscoll |
| 2022-040 | 2022 |
Salida
| Chaffee | Gregg Goodrich |