BirdAnalyst
Species · Illinois · BBS 2026 Release · 1966–2025

American Robin Population Trend in Illinois

All statesForest birds

American Robin in Illinois has surged: up 93% on the route-weighted index since 1968.

+93%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 Robin 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 →

American Robin has surged in Illinois: up 93% on the route-weighted index since 1968.

American Robin Population Forecast in Illinois

If the recent trend holds, American Robin in Illinois is projected to rise about 26% by 2030 — from 74 in 2025 to a central estimate of 93 (95% range 75–110). A 5-year backtest shows a typical error of ±41.9%, with 0% of held-out values landing inside the 95% band.

+26%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 →
93Projected 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 →
75–11095% 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 →
±41.9%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 Robin in Illinois is projected to rise about 26% by 2030 — from 74 in 2025 to a central estimate of 93 (95% range 75–110). A 5-year backtest shows a typical error of ±41.9%, with 0% 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 →
20268972107
20279073107
20289174108
20299274109
20309375110

American Robin Survey Routes in Illinois

Routes recording American Robin 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 →
Sheffield16020241966
Wayne16020251966
Terre Haute15820251966
Caledonia14920251993
Pontiac14420251978
Mackinaw14320251966
Seneca14220251993
Harristown14220252001
Atkinson13820241966
Gulfport12820251971
New Lenox12520191966
Itasca12420251966
Newark12220221969
Sherrard12020251993
Streator11420251972
Essex11120251969
Buda11020231977
Cameron11020251966
Concord10920251967
Fairland10720251967
Milford10120251966
Troy Grove10020251993
Fairbury9920251976
Humboldt9620251970
Jamestown9420251966

American Robin Population Trend in Other States

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

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