Guild · Illinois · BBS 2025 Release · 1966–2024
Grassland Birds In Illinois
14 species in this guild. As a group they are -71% since 1968.
Guild Signals
guild collapsecomputed index
Grassland birds as a group have fallen sharply in Illinois, down 71% since 1968.
Forecast
If the recent trend holds, Grassland birds in Illinois is projected to fall about 45% by 2029 — from 4.6 in 2024 to a central estimate of 2.5 (95% range 0.00–6.8). A 5-year backtest shows a typical error of ±35.3%, with 100% of held-out values landing inside the 95% band.
-45%Change by 2029
2.5Projected 2029 index
0.00–6.895% range
±35.3%Backtest error
| Year | Projected index | 95% low | 95% high |
|---|---|---|---|
| 2025 | 3.3 | 0.00 | 7.5 |
| 2026 | 3.1 | 0.00 | 7.3 |
| 2027 | 2.9 | 0.00 | 7.1 |
| 2028 | 2.7 | 0.00 | 7.0 |
| 2029 | 2.5 | 0.00 | 6.8 |
Member Species In Illinois
| Western Meadowlark | Icteridae | -98% |
| Bobolink | Icteridae | -97% |
| Grasshopper Sparrow | Passerellidae | -94% |
| Savannah Sparrow | Passerellidae | -86% |
| Ring-necked Pheasant | Phasianidae | -80% |
| Northern Bobwhite | Odontophoridae | -80% |
| Lark Sparrow | Passerellidae | -77% |
| Eastern Meadowlark | Icteridae | -73% |
| Horned Lark | Alaudidae | -71% |
| Sedge Wren | Troglodytidae | -55% |
| Upland Sandpiper | Scolopacidae | -47% |
| Vesper Sparrow | Passerellidae | -44% |
| Dickcissel | Cardinalidae | -37% |
| Henslow's Sparrow | Passerellidae | +51% |
Source: USGS North American Breeding Bird Survey, retrieved 2026-05-22.