Species · Colorado · BBS 2025 Release · 1966–2024
Dusky Grouse Population Trend in Colorado
Dusky Grouse in Colorado has collapsed: down 78% on the route-weighted index since 1975.
-78%Since 1975
42Routes In State
38Years
Notable Dusky Grouse Trends in Colorado
long arc declinecomputed index
Dusky Grouse has collapsed in Colorado: down 78% on the route-weighted index since 1975.
Dusky Grouse Population Forecast in Colorado
If the recent trend holds, Dusky Grouse in Colorado is projected to fall about 77% by 2029 — from 0.06 in 2024 to a central estimate of 0.01 (95% range 0.00–0.09). A 5-year backtest shows a typical error of ±58.4%, with 100% of held-out values landing inside the 95% band.
-77%Change by 2029
0.01Projected 2029 index
0.00–0.0995% range
±58.4%Backtest error
| Year | Projected index | 95% low | 95% high |
|---|---|---|---|
| 2025 | 0.02 | 0.00 | 0.10 |
| 2026 | 0.02 | 0.00 | 0.10 |
| 2027 | 0.02 | 0.00 | 0.10 |
| 2028 | 0.01 | 0.00 | 0.10 |
| 2029 | 0.01 | 0.00 | 0.09 |
Dusky Grouse Survey Routes in Colorado
| Pagosa Spgs | 5 | 1975 | 1975 |
| Radium | 4 | 1998 | 1998 |
| Dunckley Pas | 2 | 2024 | 1999 |
| Yellowjacket Pass | 2 | 2018 | 2017 |
| Colona 2 | 2 | 2021 | 2015 |
| Blackhead Pk | 2 | 2021 | 1991 |
| Yampa | 1 | 2007 | 2007 |
| Mount Evans | 1 | 2001 | 2001 |
| Mesaverde Np | 1 | 2010 | 2001 |
| Douglas Pass | 1 | 2024 | 2024 |
| Aspen | 1 | 1998 | 1998 |
| Cheesman Lk | 1 | 2015 | 1969 |
| Delta | 1 | 1976 | 1976 |
| Colona | 1 | 2007 | 1994 |
| Summitville | 1 | 2024 | 2009 |
| Walden | 1 | 2008 | 2006 |
| Lost Lake | 1 | 2015 | 2015 |
| Willow Peak | 1 | 2016 | 1992 |
| Uncompahgre | 1 | 2023 | 1990 |
| Castleton | 1 | 2013 | 1996 |
| Steamboat L. | 1 | 2011 | 1998 |
| Guffey | 1 | 2006 | 2006 |
| Dolores Riv | 1 | 2015 | 2003 |
| Ragged Mtn. | 1 | 2013 | 2006 |
| Como | 1 | 2018 | 2017 |
Dusky Grouse Population Trend in Other States
Source: USGS North American Breeding Bird Survey, retrieved 2026-05-22.