Species · BCR 4 · BBS 2025 Release · 1966–2024
Arctic Warbler In BCR 4
Arctic Warbler in BCR 4 has fallen sharply: down 56% on the route-weighted index since 1984.
-56%Since 1984
22Routes In Region
39Years
Notable Signals
long arc declinecomputed index
Arctic Warbler has fallen sharply in BCR 4: down 56% on the route-weighted index since 1984.
Forecast
If the recent trend holds, Arctic Warbler in BCR 4 is projected to fall about 52% by 2029 — from 3.3 in 2024 to a central estimate of 1.6 (95% range 0.00–6.3). A 5-year backtest shows a typical error of ±50.5%, with 100% of held-out values landing inside the 95% band.
-52%Change by 2029
1.6Projected 2029 index
0.00–6.395% range
±50.5%Backtest error
| Year | Projected index | 95% low | 95% high |
|---|---|---|---|
| 2025 | 1.9 | 0.00 | 6.6 |
| 2026 | 1.8 | 0.00 | 6.5 |
| 2027 | 1.8 | 0.00 | 6.4 |
| 2028 | 1.7 | 0.00 | 6.3 |
| 2029 | 1.6 | 0.00 | 6.3 |
Routes In BCR 4
| Maclaren | ALASKA | 93 | 2024 |
| Paxson Lake | ALASKA | 40 | 1997 |
| Monahan | ALASKA | 12 | 2021 |
| Toklat | ALASKA | 12 | 2024 |
| Cantwell | ALASKA | 10 | 2021 |
| Savage | ALASKA | 9 | 2024 |
| Mcgrath | ALASKA | 7 | 2022 |
| Tatalina | ALASKA | 6 | 2019 |
| Coldfoot | ALASKA | 4 | 2022 |
| Chena Hot Sp | ALASKA | 3 | 1987 |
| Ruby | ALASKA | 3 | 2024 |
| Mud River | ALASKA | 2 | 2024 |
| Pinoche Tral (Short) | ALASKA | 2 | 1984 |
| Lake Louise | ALASKA | 1 | 1997 |
| Nicholai Sl | ALASKA | 1 | 2023 |
| Petersville | ALASKA | 1 | 2011 |
| Caribou Mtn. | ALASKA | 1 | 2011 |
| Hather Creek | ALASKA | 1 | 2024 |
| Kanuti Canyn | ALASKA | 1 | 2007 |
| Ft. Richrdsn | ALASKA | 1 | 1997 |
| Anvik River | ALASKA | 1 | 1999 |
| Galena (Short) | ALASKA | 1 | 2023 |
Source: USGS North American Breeding Bird Survey, retrieved 2026-05-22.