Species · BCR 10 · BBS 2025 Release · 1966–2024
Caspian Tern In Northern Rockies
Caspian Tern in Northern Rockies has declined: down 27% on the route-weighted index since 1988.
-27%Since 1988
18Routes In Region
22Years
Notable Signals
No notable trend signals for Caspian Tern in Northern Rockies. See the full index history below.
Forecast
If the recent trend holds, Caspian Tern in Northern Rockies is projected to stay roughly flat through 2028, near 0.01 (95% range 0.00–0.05). A 5-year backtest shows a typical error of ±134.3%, with 100% of held-out values landing inside the 95% band.
n/aChange by 2028
0.01Projected 2028 index
0.00–0.0595% range
±134.3%Backtest error
| Year | Projected index | 95% low | 95% high |
|---|---|---|---|
| 2024 | 0.02 | 0.00 | 0.05 |
| 2025 | 0.02 | 0.00 | 0.05 |
| 2026 | 0.01 | 0.00 | 0.05 |
| 2027 | 0.01 | 0.00 | 0.05 |
| 2028 | 0.01 | 0.00 | 0.05 |
Routes In Northern Rockies
| Yellowstone | WYOMING | 6 | 1991 |
| Fontenelle | WYOMING | 3 | 1994 |
| Featherville | IDAHO | 2 | 2003 |
| Pablo Res. | MONTANA | 2 | 2011 |
| Monument | OREGON | 2 | 1993 |
| Cascade | IDAHO | 1 | 1984 |
| Kalispell | MONTANA | 1 | 2011 |
| Beaverhead | MONTANA | 1 | 2018 |
| Red Rock | MONTANA | 1 | 1981 |
| East Glacier Park | MONTANA | 1 | 2019 |
| Hebgen Lake | MONTANA | 1 | 2023 |
| Sparta | OREGON | 1 | 1996 |
| Neponset Res | UTAH | 1 | 2011 |
| Saleratus Cr | UTAH | 1 | 2009 |
| Colter Bay | WYOMING | 1 | 1989 |
| Fiddler Lk | WYOMING | 1 | 2023 |
| Rock River | WYOMING | 1 | 1996 |
| Harmony | WYOMING | 1 | 1989 |
Source: USGS North American Breeding Bird Survey, retrieved 2026-05-22.