Species · Colorado · BBS 2025 Release · 1966–2024
Grace's Warbler Population Trend in Colorado
Grace's Warbler in Colorado has surged: up 151% on the route-weighted index since 1980.
+151%Since 1980
18Routes In State
33Years
Notable Grace's Warbler Trends in Colorado
long arc increasecomputed index
Grace's Warbler has surged in Colorado: up 151% on the route-weighted index since 1980.
Grace's Warbler Population Forecast in Colorado
If the recent trend holds, Grace's Warbler in Colorado is projected to fall about 24% by 2029 — from 0.42 in 2024 to a central estimate of 0.32 (95% range 0.16–0.49). A 5-year backtest shows a typical error of ±21.6%, with 80% of held-out values landing inside the 95% band.
-24%Change by 2029
0.32Projected 2029 index
0.16–0.4995% range
±21.6%Backtest error
| Year | Projected index | 95% low | 95% high |
|---|---|---|---|
| 2025 | 0.31 | 0.14 | 0.47 |
| 2026 | 0.31 | 0.15 | 0.47 |
| 2027 | 0.32 | 0.15 | 0.48 |
| 2028 | 0.32 | 0.16 | 0.48 |
| 2029 | 0.32 | 0.16 | 0.49 |
Grace's Warbler Survey Routes in Colorado
| Mcphee Res. | 16 | 2024 | 1997 |
| Haycamp Mesa | 16 | 2024 | 1998 |
| Nucla | 6 | 2024 | 2000 |
| Pagosa Spgs | 5 | 1975 | 1975 |
| Cortez 2 | 4 | 2015 | 2010 |
| Cokedale | 2 | 2024 | 2019 |
| Walsenburg | 2 | 2003 | 2003 |
| Delta | 2 | 2021 | 2011 |
| Dolores | 2 | 1969 | 1969 |
| Cortez | 2 | 2006 | 1997 |
| Blackhead Pk | 2 | 1998 | 1998 |
| Animas | 1 | 1996 | 1996 |
| Ludlow | 1 | 2014 | 2009 |
| Uncompahgre | 1 | 2024 | 1999 |
| Colona | 1 | 1980 | 1980 |
| Pinon | 1 | 2023 | 2013 |
| Powderhorn | 1 | 2023 | 2008 |
| Piedra | 1 | 2015 | 1992 |
Grace's Warbler Population Trend in Other States
Source: USGS North American Breeding Bird Survey, retrieved 2026-05-22.