Species · Pennsylvania · BBS 2025 Release · 1966–2024
Cerulean Warbler Population Trend in Pennsylvania
Cerulean Warbler in Pennsylvania has held roughly steady: down 1% on the route-weighted index since 1968.
-1%Since 1968
77Routes In State
58Years
Notable Cerulean Warbler Trends in Pennsylvania
No notable trend signals for Cerulean Warbler in Pennsylvania. See the full index history below.
Cerulean Warbler Population Forecast in Pennsylvania
If the recent trend holds, Cerulean Warbler in Pennsylvania is projected to fall about 22% by 2029 — from 0.24 in 2024 to a central estimate of 0.18 (95% range 0.00–0.39). A 5-year backtest shows a typical error of ±61%, with 100% of held-out values landing inside the 95% band.
-22%Change by 2029
0.18Projected 2029 index
0.00–0.3995% range
±61%Backtest error
| Year | Projected index | 95% low | 95% high |
|---|---|---|---|
| 2025 | 0.19 | 0.00 | 0.40 |
| 2026 | 0.19 | 0.00 | 0.40 |
| 2027 | 0.19 | 0.00 | 0.40 |
| 2028 | 0.19 | 0.00 | 0.40 |
| 2029 | 0.18 | 0.00 | 0.39 |
Cerulean Warbler Survey Routes in Pennsylvania
| Landisburg | 6 | 2024 | 1978 |
| Carsonville | 5 | 1997 | 1997 |
| Roulette | 4 | 2021 | 2021 |
| Geeseytown | 4 | 2024 | 1987 |
| Broad Mtn. | 4 | 2021 | 1997 |
| Rector | 3 | 1977 | 1966 |
| Peru Mills | 3 | 2024 | 2001 |
| N Washington | 2 | 2002 | 1970 |
| Eldred | 2 | 2004 | 1995 |
| Portersville | 2 | 1976 | 1976 |
| Sardis | 2 | 1974 | 1968 |
| St College | 2 | 2009 | 1981 |
| Pine Gr Mill | 2 | 2014 | 1987 |
| Peters Mt | 2 | 1994 | 1994 |
| Jefferson | 2 | 2024 | 1966 |
| Sproul Sf-B | 2 | 2015 | 2003 |
| Espyville | 1 | 2021 | 1967 |
| Clover | 1 | 2023 | 1988 |
| Harmonsburg | 1 | 1989 | 1989 |
| Whig Hill | 1 | 2022 | 1991 |
| Akeley | 1 | 1974 | 1974 |
| Teepleville | 1 | 2006 | 1999 |
| Sigel | 1 | 2002 | 2002 |
| Lynch | 1 | 2000 | 1968 |
| N Pine Grove | 1 | 2006 | 1974 |
Cerulean Warbler Population Trend in Other States
Source: USGS North American Breeding Bird Survey, retrieved 2026-05-22.