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Species · Illinois · BBS 2026 Release · 1966–2025

Eastern Wood-Pewee Population Trend in Illinois

All statesAerial insectivores

Eastern Wood-Pewee in Illinois has surged: up 226% on the route-weighted index since 1968.

+226%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 →
104Routes 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 Eastern Wood-Pewee 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 →

Eastern Wood-Pewee has surged in Illinois: up 226% on the route-weighted index since 1968.

Eastern Wood-Pewee Population Forecast in Illinois

If the recent trend holds, Eastern Wood-Pewee in Illinois is projected to fall about 25% by 2030 — from 6.9 in 2025 to a central estimate of 5.2 (95% range 3.5–6.9). A 5-year backtest shows a typical error of ±36.9%, with 0% of held-out values landing inside the 95% band.

-25%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 →
5.2Projected 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 →
3.5–6.995% 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 →
±36.9%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, Eastern Wood-Pewee in Illinois is projected to fall about 25% by 2030 — from 6.9 in 2025 to a central estimate of 5.2 (95% range 3.5–6.9). A 5-year backtest shows a typical error of ±36.9%, 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 →
20265.03.36.7
20275.03.36.7
20285.13.46.8
20295.13.46.9
20305.23.56.9

Eastern Wood-Pewee Survey Routes in Illinois

Routes recording Eastern Wood-Pewee 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 →
Belleview3720251966
Eldred3120251993
Cave In Rock2820241993
Bremen1920251969
Lake Galena1820212001
Athensville1720251971
Delwood1620251970
Beaverdam Lk1620231970
York1620251994
Concord1520251967
Bradbury1520251970
Clayton1420252008
Eubanks1420252001
Dudleyville1420252001
Sheffield1320241966
St Morgan1320221967
Sandusky1320231993
Brnt Prairie1220251976
Mt Vernon1220251971
Camp Point1220251993
Duncan Mills1220251993
Royalton1220252001
Athens1220251995
Sherrard1120252005
Marshall1120252001

Eastern Wood-Pewee Population Trend in Other States

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

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