Species · BCR 11 · BBS 2025 Release · 1966–2024
Brewer's Sparrow In Prairie Potholes
Brewer's Sparrow in Prairie Potholes has surged: up 103% on the route-weighted index since 1972.
+103%Since 1972
19Routes In Region
51Years
Notable Signals
long arc increasecomputed index
Brewer's Sparrow has surged in Prairie Potholes: up 103% on the route-weighted index since 1972.
Forecast
If the recent trend holds, Brewer's Sparrow in Prairie Potholes is projected to rise about 22% by 2029 — from 0.31 in 2024 to a central estimate of 0.38 (95% range 0.04–0.72). A 5-year backtest shows a typical error of ±22.7%, with 100% of held-out values landing inside the 95% band.
+22%Change by 2029
0.38Projected 2029 index
0.04–0.7295% range
±22.7%Backtest error
| Year | Projected index | 95% low | 95% high |
|---|---|---|---|
| 2025 | 0.36 | 0.02 | 0.70 |
| 2026 | 0.37 | 0.02 | 0.71 |
| 2027 | 0.37 | 0.03 | 0.71 |
| 2028 | 0.37 | 0.03 | 0.72 |
| 2029 | 0.38 | 0.04 | 0.72 |
Routes In Prairie Potholes
| Cleveland | MONTANA | 12 | 2024 |
| Harlem | MONTANA | 8 | 2021 |
| Shelby | MONTANA | 6 | 2022 |
| Malta | MONTANA | 5 | 2024 |
| Oswego | MONTANA | 4 | 2001 |
| Ester Lake | MONTANA | 4 | 2023 |
| Virgelle | MONTANA | 2 | 2024 |
| Gildford | MONTANA | 2 | 2016 |
| Chinook | MONTANA | 2 | 2024 |
| Lambert | MONTANA | 2 | 2022 |
| Hay Lake | MONTANA | 1 | 2021 |
| Sunburst | MONTANA | 1 | 2003 |
| Glasgow | MONTANA | 1 | 2021 |
| Redstone | MONTANA | 1 | 2022 |
| Great Falls | MONTANA | 1 | 1988 |
| Whitlash | MONTANA | 1 | 2024 |
| Saco | MONTANA | 1 | 2019 |
| Glentana | MONTANA | 1 | 2015 |
| Wolf Point | MONTANA | 1 | 2018 |
Source: USGS North American Breeding Bird Survey, retrieved 2026-05-22.