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

House Finch Population Trend in Illinois

All statesGeneralists

House Finch in Illinois has surged: up 26× on the route-weighted index since 1989.

26×Since 1989TrendPercent 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 →
37YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable House Finch 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 →

House Finch has surged in Illinois: up 26× on the route-weighted index since 1989.

House Finch Population Forecast in Illinois

If the recent trend holds, House Finch in Illinois is projected to fall about 10% by 2029 — from 4.9 in 2024 to a central estimate of 4.4 (95% range 1.1–7.7). A 5-year backtest shows a typical error of ±12.6%, with 100% of held-out values landing inside the 95% band.

-10%Change by 2029TrendPercent 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 →
4.4Projected 2029 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
1.1–7.795% 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 →
±12.6%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, House Finch in Illinois is projected to fall about 10% by 2029 — from 4.9 in 2024 to a central estimate of 4.4 (95% range 1.1–7.7). A 5-year backtest shows a typical error of ±12.6%, with 100% of held-out values landing inside the 95% band.19872029
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 →
20254.31.07.6
20264.31.17.6
20274.41.17.7
20284.41.17.7
20294.41.17.7

House Finch Survey Routes in Illinois

Routes recording House Finch 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 →
Wayne4120241990
Itasca2420241988
Sheffield1420241991
New Lenox1420191988
Williamsfld1220241992
Seneca1220241993
Terre Haute1120241989
Beaucoup1120241992
Mt Vernon1120241990
Union1120172001
Pontiac1020241993
Belleview1020241990
Harristown1020242001
Cameron920241988
Bartonville920241992
Mackinaw920241991
Janesville920241992
Columbia920241992
Cherry Val 2920182004
Buda820231994
Newark820221989
Monticello820241989
Lake Summerset820222001
Dudleyville820242001
Cherry Val720031990

House Finch Population Trend in Other States

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

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