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Species · Illinois · BBS 2026 Release · 1966–2025

Red-shouldered Hawk Population Trend in Illinois

All statesBirds of prey

Red-shouldered Hawk in Illinois has surged: up 20× on the route-weighted index since 1969.

20×Since 1969TrendPercent 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 →
51Routes 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 →
57YearsYears 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-shouldered Hawk 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 Red-shouldered Hawk in Illinois. See the full index history below.

Red-shouldered Hawk Population Forecast in Illinois

If the recent trend holds, Red-shouldered Hawk in Illinois is projected to fall about 34% by 2030 — from 0.89 in 2025 to a central estimate of 0.59 (95% range 0.19–0.99). A 5-year backtest shows a typical error of ±65.7%, with 0% of held-out values landing inside the 95% band.

-34%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 →
0.59Projected 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 →
0.19–0.9995% 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 →
±65.7%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-shouldered Hawk in Illinois is projected to fall about 34% by 2030 — from 0.89 in 2025 to a central estimate of 0.59 (95% range 0.19–0.99). A 5-year backtest shows a typical error of ±65.7%, 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 →
20260.550.140.95
20270.560.150.96
20280.570.160.97
20290.580.170.98
20300.590.190.99

Red-shouldered Hawk Survey Routes in Illinois

Routes recording Red-shouldered Hawk 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 →
Beaverdam Lk1320231970
Pulaski1020251970
Belknap1020251983
York820252001
Belleview520251991
Dudleyville520252001
Mt Vernon420251990
Birds420222022
Bremen420251984
Delwood420251970
Robinson420232021
Marshall420252013
Royalton420252008
Cave In Rock420242001
Athens220162016
Clayton220232023
Pawnee220232023
Bradbury220242005
Martinsville220222022
Mascoutah Lk220241991
St Morgan220221988
Olney220241966
Karnak220252006
Sandusky220231999
Mill Creek120102010

Red-shouldered Hawk Population Trend in Other States

alabamaarkansascaliforniaconnecticutdelawarefloridageorgiaindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourinebraskanew-hampshirenew-jerseynew-yorknorth-carolinaohiooklahomaoregonpennsylvaniarhode-islandsouth-carolinatennesseetexasvermontvirginiawashingtonwest-virginiawisconsin

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