| Acc. No. | Year | Location | County | Observers |
| 52-74-177 | 1965 |
Golden
| Jefferson | George Shier |
| 52-74-179 | 1967 |
Powell Mesa
| Delta | Theodora Colborn |
| 52-74-160 | 1974 |
Loveland
| Larimer | Allegra Collister, Camille Cummings, Lois Matthews, Bob Andrews, Jack Reddall |
| 2005-120 | 2005 |
Rifle Mountain Park
| Garfield | Fred Fisher, Andrew Spencer, Glenn Walbek |
| 2007-026 | 2007 |
Canon City Riverwalk
| Fremont | Andrew Spencer, Bill Maynard, Brandon Percival, Doug Faulkner, Nathan Pieplow, Peter Gent, Rachel Hopper, Tony Leukering |
| 2013-148 | 2013 |
Bauer Lake
| Montezuma | Nicholas Komar |
| 2014-046 | 2014 |
Crow Valley Campground
| Weld | Cathy Sheeter, Kris Petersen, Scott Manwaring, Sue Riffe, Mark Minner-Lee, Steven Mlodinow, Rudi Nuissl |
| 2015-041 | 2015 |
Black Canyon of the Gunnison National Park
| Montrose | Matthew DeSaix |
| 2019-008 | 2019 |
Eads
| Kiowa | Brandon K. Percival, Tony Leukering |
| 2019-009 | 2019 |
Lamar Community College
| Prowers | Dorothy Russell |
| 2021-034 | 2021 |
Box Canyon Falls Park
| Ouray | Cliff Utech |