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

Eastern Towhee Population Trend in Illinois

All statesGeneralists

Eastern Towhee in Illinois has increased: up 34% on the route-weighted index since 1968.

+34%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 →
101Routes 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 →
58YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Eastern Towhee 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 Eastern Towhee in Illinois. See the full index history below.

Eastern Towhee Population Forecast in Illinois

If the recent trend holds, Eastern Towhee in Illinois is projected to fall about 17% by 2029 — from 2.4 in 2024 to a central estimate of 2.0 (95% range 0.82–3.2). A 5-year backtest shows a typical error of ±11.1%, with 100% of held-out values landing inside the 95% band.

-17%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 →
2.0Projected 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 →
0.82–3.295% 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 →
±11.1%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, Eastern Towhee in Illinois is projected to fall about 17% by 2029 — from 2.4 in 2024 to a central estimate of 2.0 (95% range 0.82–3.2). A 5-year backtest shows a typical error of ±11.1%, with 100% of held-out values landing inside the 95% band.19662029
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 →
20252.00.813.2
20262.00.813.2
20272.00.813.2
20282.00.823.2
20292.00.823.2

Eastern Towhee Survey Routes in Illinois

Routes recording Eastern Towhee 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 →
Royalton2020242001
York1720241993
Delwood1320241970
Belknap1220241970
Mascoutah Lk720241968
Bremen720241969
Cave In Rock720241993
Eubanks720222001
Marshall720242010
Kell720242001
Karnak720242001
Sheffield520241966
Bradbury520241971
St Morgan520221967
Guilford420231967
Cherry Val420031972
Chandlervill420221971
Pawnee420241967
Beaucoup420241971
Mt Vernon420241971
Birds420241976
Sherrard420241993
Camp Point420231993
Sandusky420231993
Clayton420242009

Eastern Towhee Population Trend in Other States

alabamaarkansasconnecticutdelawarefloridageorgiaindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanew-hampshirenew-jerseynew-yorknorth-carolinanorth-dakotaohiooklahomapennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasvermontvirginiawest-virginiawisconsinwyoming

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