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Species · Illinois · BBS 2025 Release · 1966–2024

Red-bellied Woodpecker Population Trend in Illinois

All statesForest birds

Red-bellied Woodpecker in Illinois has surged: up 257% on the route-weighted index since 1968.

+257%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 →
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 Red-bellied Woodpecker 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 →

Red-bellied Woodpecker has surged in Illinois: up 256% on the route-weighted index since 1968.

Red-bellied Woodpecker Population Forecast in Illinois

If the recent trend holds, Red-bellied Woodpecker in Illinois is projected to rise about 20% by 2029 — from 6.9 in 2024 to a central estimate of 8.3 (95% range 6.5–10). A 5-year backtest shows a typical error of ±19.5%, with 80% of held-out values landing inside the 95% band.

+20%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 →
8.3Projected 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 →
6.5–1095% 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 →
±19.5%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, Red-bellied Woodpecker in Illinois is projected to rise about 20% by 2029 — from 6.9 in 2024 to a central estimate of 8.3 (95% range 6.5–10). A 5-year backtest shows a typical error of ±19.5%, with 80% 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 →
20258.06.19.8
20268.06.29.8
20278.16.39.9
20288.26.410
20298.36.510

Red-bellied Woodpecker Survey Routes in Illinois

Routes recording Red-bellied Woodpecker 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 →
Bremen3420241969
Belleview3020241966
St Morgan2620221967
Pulaski2120241970
Mascoutah Lk2020241967
York1920241993
Belknap1820241970
Royalton1720242001
Terre Haute1620241966
Concord1620241967
Sandusky1620231993
Athensville1520241971
Kell1420242001
Guilford1320231967
Mt Vernon1320241972
Cave In Rock1320241993
Mill Creek1220241970
Delwood1120241970
Athens1120241995
Eubanks1020242001
Dudleyville1020242001
Wayne920241988
Melrose919991973
Pawnee920241967
Beaucoup920241972

Red-bellied Woodpecker Population Trend in Other States

alabamaarkansasconnecticutdelawarefloridageorgiaindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourinebraskanew-hampshirenew-jerseynew-yorknorth-carolinanorth-dakotaohiooklahomapennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasvermontvirginiawest-virginiawisconsin

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