Species · BCR 15 · BBS 2025 Release · 1966–2024
Mountain Bluebird In Sierra Nevada
Mountain Bluebird in Sierra Nevada has fallen sharply: down 72% on the route-weighted index since 1971.
-72%Since 1971
22Routes In Region
55Years
Notable Signals
long arc declinecomputed index
Mountain Bluebird has fallen sharply in Sierra Nevada: down 72% on the route-weighted index since 1971.
Forecast
If the recent trend holds, Mountain Bluebird in Sierra Nevada is projected to fall about 31% by 2029 — from 0.95 in 2024 to a central estimate of 0.66 (95% range 0.00–2.0). A 5-year backtest shows a typical error of ±83%, with 100% of held-out values landing inside the 95% band.
-31%Change by 2029
0.66Projected 2029 index
0.00–2.095% range
±83%Backtest error
| Year | Projected index | 95% low | 95% high |
|---|---|---|---|
| 2025 | 0.67 | 0.00 | 2.0 |
| 2026 | 0.67 | 0.00 | 2.0 |
| 2027 | 0.66 | 0.00 | 2.0 |
| 2028 | 0.66 | 0.00 | 2.0 |
| 2029 | 0.66 | 0.00 | 2.0 |
Routes In Sierra Nevada
| Goumaz | CALIFORNIA | 14 | 2011 |
| Chilcoot | CALIFORNIA | 11 | 2024 |
| Sattley | CALIFORNIA | 8 | 2015 |
| Eagle Lake | CALIFORNIA | 4 | 2024 |
| Pine Mountain | CALIFORNIA | 4 | 2017 |
| Johnsville | CALIFORNIA | 3 | 2014 |
| Tuolumne Grove | CALIFORNIA | 3 | 2016 |
| Genesee | CALIFORNIA | 2 | 2023 |
| Riverton | CALIFORNIA | 2 | 2004 |
| Hat Creek | CALIFORNIA | 2 | 2017 |
| Little Truckee | CALIFORNIA | 2 | 2023 |
| Pollock Pines | CALIFORNIA | 2 | 2024 |
| Last Chance | CALIFORNIA | 2 | 2019 |
| Lassen Park | CALIFORNIA | 1 | 1988 |
| Westville | CALIFORNIA | 1 | 2023 |
| Dardanelle | CALIFORNIA | 1 | 2019 |
| Woodfords | CALIFORNIA | 1 | 2001 |
| Greenhorn Mt | CALIFORNIA | 1 | 1984 |
| Lakeshore | CALIFORNIA | 1 | 2001 |
| Paxton | CALIFORNIA | 1 | 2000 |
| Meadow Valley | CALIFORNIA | 1 | 1999 |
| Crestview | CALIFORNIA | 1 | 2024 |
Source: USGS North American Breeding Bird Survey, retrieved 2026-05-22.