Species · BCR 16 · BBS 2025 Release · 1966–2024
Brown-headed Cowbird In Southern Rockies / Colorado Plateau
Brown-headed Cowbird in Southern Rockies / Colorado Plateau has increased: up 49% on the route-weighted index since 1970.
+49%Since 1970
234Routes In Region
56Years
Notable Signals
No notable trend signals for Brown-headed Cowbird in Southern Rockies / Colorado Plateau. See the full index history below.
Forecast
If the recent trend holds, Brown-headed Cowbird in Southern Rockies / Colorado Plateau is projected to rise about 37% by 2029 — from 2.5 in 2024 to a central estimate of 3.4 (95% range 0.17–6.6). A 5-year backtest shows a typical error of ±75.1%, with 100% of held-out values landing inside the 95% band.
+37%Change by 2029
3.4Projected 2029 index
0.17–6.695% range
±75.1%Backtest error
| Year | Projected index | 95% low | 95% high |
|---|---|---|---|
| 2025 | 3.5 | 0.25 | 6.7 |
| 2026 | 3.4 | 0.23 | 6.7 |
| 2027 | 3.4 | 0.21 | 6.6 |
| 2028 | 3.4 | 0.19 | 6.6 |
| 2029 | 3.4 | 0.17 | 6.6 |
Routes In Southern Rockies / Colorado Plateau
| Falfa | COLORADO | 29 | 2024 |
| Dolores | COLORADO | 26 | 1987 |
| Ragged Mtn. | COLORADO | 20 | 2019 |
| Aztec | NEW-MEXICO | 18 | 1989 |
| Douglas Pass | COLORADO | 17 | 2024 |
| Pleasant View | COLORADO | 17 | 2021 |
| Pinos Creek | COLORADO | 15 | 1990 |
| Capulin | NEW-MEXICO | 15 | 1993 |
| Pagosa Spgs | COLORADO | 14 | 1982 |
| Pastura | NEW-MEXICO | 14 | 2016 |
| Beck | UTAH | 13 | 1987 |
| Yampa | COLORADO | 12 | 2023 |
| Guffey | COLORADO | 12 | 2024 |
| Yellowjacket Pass | COLORADO | 12 | 2024 |
| Wellington 2 | UTAH | 12 | 2011 |
| Alamosa | COLORADO | 11 | 2024 |
| Aspen | COLORADO | 10 | 2024 |
| Fruita | COLORADO | 10 | 2007 |
| Tarryall | COLORADO | 10 | 2023 |
| Walsenburg | COLORADO | 10 | 2024 |
| Claunch 2 | NEW-MEXICO | 10 | 2024 |
| The Gap | ARIZONA | 9 | 1976 |
| Angora | COLORADO | 8 | 2024 |
| Stillwater Pass | COLORADO | 8 | 2009 |
| Animas 2 | COLORADO | 8 | 2018 |
Source: USGS North American Breeding Bird Survey, retrieved 2026-05-22.