| | Acc. No. | Year | Location | County | Observers |
| N-52-55 | 1975 |
Cottonwood Canyon
| Las Animas | Lois Webster |
| 52-77-23 | 1977 |
South Republican SWA
| Yuma | Mike Moulton, William Lybarger |
| 52-89-47 | 1989 |
Burchfield State Wildlife Area
| Baca | Mark Janos |
| 52-96-84 | 1996 |
Prewitt Reservoir State Wildlife Area
| Washington | Dave Leatherman |
| 2008-033 | 2008 |
Longmont
| Boulder | Mark Miller, Andrew Spencer, Bill Kaempfer, Bill Maynard, Bill Schmoker, Brandon Percival, Gregg Goodrich, Nathan Pieplow, Rachel Hopper, Thomas Lechleitner, Walter Szeliga |
| 2017-026 | 2017 |
Brett Gray Ranch
| Lincoln | Steven Mlodinow |
| 2020-013 | 2020 |
Spring Creek Trail
| Larimer | Jessie Reese, Rachel Hopper, Joe Mammoser |
| 2022-063 | 2022 |
Brett Gray Ranch
| Lincoln | Luke Pheneger |