Species · Montana · BBS 2025 Release · 1966–2024
Northern Waterthrush Population Trend in Montana
Northern Waterthrush in Montana has surged: up 592% on the route-weighted index since 1973.
+592%Since 1973
43Routes In State
53Years
Notable Northern Waterthrush Trends in Montana
long arc increasecomputed index
Northern Waterthrush has surged in Montana: up 591% on the route-weighted index since 1973.
Northern Waterthrush Population Forecast in Montana
If the recent trend holds, Northern Waterthrush in Montana is projected to rise about 36% by 2029 — from 0.82 in 2024 to a central estimate of 1.1 (95% range 0.50–1.7). A 5-year backtest shows a typical error of ±27.6%, with 100% of held-out values landing inside the 95% band.
+36%Change by 2029
1.1Projected 2029 index
0.50–1.795% range
±27.6%Backtest error
| Year | Projected index | 95% low | 95% high |
|---|---|---|---|
| 2025 | 1.1 | 0.46 | 1.7 |
| 2026 | 1.1 | 0.47 | 1.7 |
| 2027 | 1.1 | 0.48 | 1.7 |
| 2028 | 1.1 | 0.49 | 1.7 |
| 2029 | 1.1 | 0.50 | 1.7 |
Northern Waterthrush Survey Routes in Montana
| East Glacier Park | 18 | 2024 | 2015 |
| Sula | 7 | 2024 | 1977 |
| Logan Pass | 6 | 2024 | 1980 |
| Elliston | 6 | 2024 | 1972 |
| St. Mary 2 | 6 | 2024 | 2009 |
| Whitefish Lake | 5 | 2024 | 2018 |
| Wise River | 5 | 2024 | 1998 |
| Inside Road | 4 | 2024 | 1990 |
| Swan Lake | 4 | 2024 | 2017 |
| Ninemile | 3 | 2024 | 1995 |
| Libby Dam | 2 | 2024 | 1979 |
| St Mary | 2 | 2008 | 1977 |
| Threemile Wa | 2 | 1993 | 1993 |
| Arlee | 2 | 2024 | 1972 |
| Augusta | 2 | 2022 | 1978 |
| Thompson Riv | 2 | 2022 | 2014 |
| Pagil Gulch | 2 | 2021 | 2015 |
| Clyde Park | 2 | 2022 | 2018 |
| Painted Rock | 2 | 2022 | 1993 |
| Kalispell | 1 | 2023 | 1970 |
| Victor | 1 | 2006 | 1997 |
| Cramer Creek | 1 | 2008 | 2008 |
| Glen | 1 | 2010 | 1977 |
| Willow Creek 2 | 1 | 2016 | 2013 |
| Greenough | 1 | 2004 | 2002 |
Northern Waterthrush Population Trend in Other States
Source: USGS North American Breeding Bird Survey, retrieved 2026-05-22.