BirdAnalyst
Species · Illinois · BBS 2025 Release · 1966–2024

Prairie Warbler Population Trend in Illinois

All statesForest birds

Prairie Warbler in Illinois has surged: up 194% on the route-weighted index since 1973.

+194%Since 1973
22Routes In State
53Years

Notable Prairie Warbler Trends in Illinois

long arc increasecomputed index

Prairie Warbler has surged in Illinois: up 194% on the route-weighted index since 1973.

Prairie Warbler Population Forecast in Illinois

If the recent trend holds, Prairie Warbler in Illinois is projected to fall about 36% by 2029 — from 0.25 in 2024 to a central estimate of 0.16 (95% range 0.01–0.32). A 5-year backtest shows a typical error of ±61.4%, with 20% of held-out values landing inside the 95% band.

-36%Change by 2029
0.16Projected 2029 index
0.01–0.3295% range
±61.4%Backtest error
19712029
Projection of the recent trend (dashed) with 80/95% bands — a projection, not a prediction. Habitat, climate, and land use are not modeled.
YearProjected index95% low95% high
20250.160.000.31
20260.160.000.31
20270.160.000.32
20280.160.000.32
20290.160.010.32

Prairie Warbler Survey Routes in Illinois

Routes recording Prairie Warbler in Illinois.
Delwood620241972
Belknap520241971
Belleview420242016
Beaverdam Lk320231974
Robinson320222021
Camp Point219971997
Cave In Rock220241993
Dailey120002000
Milford119921992
Clarksdale120232023
Brnt Prairie119761976
Mt Vernon120142014
Eubanks120242010
Birds120232023
Pulaski120031971
Bremen120221972
Royalton120142014
Karnak120232012
Nilwood120012001
York120242024
Brownville120232015
Sandusky120221997

Prairie Warbler Population Trend in Other States

alabamaarkansascaliforniaconnecticutdelawarefloridageorgiaindianakentuckylouisianamainemarylandmassachusettsmichiganmississippimissourinew-hampshirenew-jerseynew-yorknorth-carolinaohiooklahomapennsylvaniarhode-islandsouth-carolinatennesseetexasvermontvirginiawest-virginiawisconsin

Source: USGS North American Breeding Bird Survey, retrieved 2026-05-22.