Species · Illinois · BBS 2025 Release · 1966–2024
Bell's Vireo Population Trend in Illinois
Bell's Vireo in Illinois has held roughly steady: up 9% on the route-weighted index since 1968.
+9%Since 1968
73Routes In State
58Years
Notable Bell's Vireo Trends in Illinois
No notable trend signals for Bell's Vireo in Illinois. See the full index history below.
Bell's Vireo Population Forecast in Illinois
If the recent trend holds, Bell's Vireo in Illinois is projected to fall about 62% by 2029 — from 0.45 in 2024 to a central estimate of 0.17 (95% range 0.00–0.40). A 5-year backtest shows a typical error of ±68.4%, with 40% of held-out values landing inside the 95% band.
-62%Change by 2029
0.17Projected 2029 index
0.00–0.4095% range
±68.4%Backtest error
| Year | Projected index | 95% low | 95% high |
|---|---|---|---|
| 2025 | 0.17 | 0.00 | 0.40 |
| 2026 | 0.17 | 0.00 | 0.40 |
| 2027 | 0.17 | 0.00 | 0.40 |
| 2028 | 0.17 | 0.00 | 0.40 |
| 2029 | 0.17 | 0.00 | 0.40 |
Bell's Vireo Survey Routes in Illinois
| Chandlervill | 4 | 2024 | 1971 |
| Kell | 4 | 2024 | 2001 |
| Beaucoup | 3 | 2024 | 1974 |
| Pulaski | 3 | 2024 | 2009 |
| Brownville | 3 | 2024 | 1998 |
| Geneseo | 2 | 1987 | 1967 |
| Concord | 2 | 1996 | 1967 |
| Belleview | 2 | 2023 | 1966 |
| Humboldt | 2 | 2018 | 2005 |
| Martinsville | 2 | 2018 | 1972 |
| Robinson | 2 | 2022 | 1977 |
| Royalton | 2 | 2024 | 2007 |
| York | 2 | 2024 | 2004 |
| Darmstadt | 2 | 2024 | 2014 |
| Guilford | 1 | 2001 | 2001 |
| Cherry Val | 1 | 1972 | 1972 |
| Atkinson | 1 | 2024 | 2024 |
| Payson | 1 | 2022 | 2009 |
| Sheffield | 1 | 2011 | 1968 |
| Buda | 1 | 2016 | 2016 |
| Wayne | 1 | 1998 | 1998 |
| Waynesville | 1 | 2007 | 2003 |
| Dudleyville | 1 | 2022 | 2006 |
| New Lenox | 1 | 1981 | 1981 |
| Stillwell | 1 | 2011 | 1971 |
Bell's Vireo Population Trend in Other States
Source: USGS North American Breeding Bird Survey, retrieved 2026-05-22.