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Species · Illinois · BBS 2026 Release · 1966–2025

Yellow-breasted Chat Population Trend in Illinois

All statesForest birds

Yellow-breasted Chat in Illinois has surged: up 170% on the route-weighted index since 1968.

+170%Since 1968TrendPercent change in the route-weighted abundance index between a smoothed baseline window and the most recent one. It tracks direction, not absolute population.Full methodology →
84Routes In StateSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
59YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Yellow-breasted Chat Trends in IllinoisNotable signalsLong-arc shifts the engine flags automatically — sustained declines or increases large enough to stand out from year-to-year noise.Full methodology →

long arc increasecomputed indexTrend sourceWhether the figure is our own computed route-weighted index or an official USGS modeled estimate. The current build labels every trend as computed.Full methodology →

Yellow-breasted Chat has surged in Illinois: up 170% on the route-weighted index since 1968.

Yellow-breasted Chat Population Forecast in Illinois

If the recent trend holds, Yellow-breasted Chat in Illinois is projected to fall about 20% by 2030 — from 2.9 in 2025 to a central estimate of 2.4 (95% range 0.80–3.9). A 5-year backtest shows a typical error of ±36.7%, with 80% of held-out values landing inside the 95% band.

-20%Change by 2030TrendPercent change in the route-weighted abundance index between a smoothed baseline window and the most recent one. It tracks direction, not absolute population.Full methodology →
2.4Projected 2030 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.80–3.995% range95% rangeThe 95% uncertainty band around the projection at the forecast horizon. The true value should land inside it most of the time.Full methodology →
±36.7%Backtest errorBacktest errorTypical error when we hold out the most recent years, forecast them, and compare to what actually happened. Lower means a more trustworthy projection.Full methodology →
If the recent trend holds, Yellow-breasted Chat in Illinois is projected to fall about 20% by 2030 — from 2.9 in 2025 to a central estimate of 2.4 (95% range 0.80–3.9). A 5-year backtest shows a typical error of ±36.7%, with 80% of held-out values landing inside the 95% band.19662030
Projection of the recent trend (dashed) with 80/95% bands — a projection, not a prediction. Habitat, climate, and land use are not modeled.
YearProjected indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →95% low95% rangeThe 95% uncertainty band around the projection at the forecast horizon. The true value should land inside it most of the time.Full methodology →95% high95% rangeThe 95% uncertainty band around the projection at the forecast horizon. The true value should land inside it most of the time.Full methodology →
20262.30.763.9
20272.30.773.9
20282.30.783.9
20292.30.793.9
20302.40.803.9

Yellow-breasted Chat Survey Routes in Illinois

Routes recording Yellow-breasted Chat in Illinois.
Recent countThe raw number of individuals recorded on this route in its most recent survey year. A single-route tally, not a trend.Full methodology →
Belknap2320251970
Beaverdam Lk2120231970
Sandusky2120231993
Delwood1920251970
Brownville1820251993
Royalton1420252001
Belleview1320251966
Pulaski1320251970
Cave In Rock1320241993
Karnak1220252001
Bradbury1120251970
Bremen1120251969
Brnt Prairie1020251976
York920251999
Kell920252001
Robinson820231970
Mt Vernon720251971
Columbia420231966
Beaucoup420251971
Olney420241966
Marshall420252010
Putnam320051982
Pawnee320251967
Janesville320251973
Mascoutah Lk320251967

Yellow-breasted Chat Population Trend in Other States

alabamaarizonaarkansascaliforniacoloradoconnecticutdelawarefloridageorgiaidahoindianaiowakansaskentuckylouisianamarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanevadanew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniasouth-carolinasouth-dakotatennesseetexasutahvirginiawashingtonwest-virginiawisconsinwyoming

Source: USGS North American Breeding Bird Survey, retrieved 2026-08-14.