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Species · Illinois · BBS 2026 Release · 1966–2025

American Goldfinch Population Trend in Illinois

All statesForest birds

American Goldfinch in Illinois has held roughly steady: up 1% on the route-weighted index since 1968.

+1%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 →
105Routes 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 American Goldfinch 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 →

No notable trend signals for American Goldfinch in Illinois. See the full index history below.

American Goldfinch Population Forecast in Illinois

If the recent trend holds, American Goldfinch in Illinois is projected to stay roughly flat through 2030, near 9.7 (95% range 5.8–14). A 5-year backtest shows a typical error of ±13.4%, with 100% of held-out values landing inside the 95% band.

+7%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 →
9.7Projected 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 →
5.8–1495% 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 →
±13.4%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, American Goldfinch in Illinois is projected to stay roughly flat through 2030, near 9.7 (95% range 5.8–14). A 5-year backtest shows a typical error of ±13.4%, with 100% 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 →
20269.65.714
20279.65.714
20289.75.814
20299.75.814
20309.75.814

American Goldfinch Survey Routes in Illinois

Routes recording American Goldfinch 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 →
Wayne5220251966
York5020251993
Melrose2919991973
Belleview2720251966
New Lenox2420191966
Fairbury2420251976
Grape Creek2320252001
Chandlervill2220251971
Sheffield2120241966
Union2120172001
Guilford2020231967
Brownville1820251993
Atkinson1720241966
Fairland1720251967
Bremen1720251969
Gulfport1620251971
Caledonia1620251993
Sherrard1620251993
Cave In Rock1620241993
Delwood1520251970
Camp Point1520251993
Sandusky1520231993
Beaverdam Lk1420231970
Eldred1420251993
Itasca1320251973

American Goldfinch Population Trend in Other States

alabamaarkansascaliforniacoloradoconnecticutdelawaregeorgiaidahoindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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