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Species · Illinois · BBS 2025 Release · 1966–2024

Western Cattle-Egret Population Trend in Illinois

All statesWetland birds

Western Cattle-Egret in Illinois has collapsed: down 94% on the route-weighted index since 1974.

-94%Since 1974TrendPercent 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 →
16Routes 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 →
38YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Western Cattle-Egret 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 declinecomputed 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 →

Western Cattle-Egret has collapsed in Illinois: down 94% on the route-weighted index since 1974.

Western Cattle-Egret Population Forecast in Illinois

If the recent trend holds, Western Cattle-Egret in Illinois is projected to stay roughly flat through 2029, near 0.13 (95% range 0.00–0.79). A 5-year backtest shows a typical error of ±1299.1%, with 100% of held-out values landing inside the 95% band.

n/aChange 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 →
0.13Projected 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 →
0.00–0.7995% 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 →
±1299.1%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 →
19702029
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 →
20250.150.000.81
20260.140.000.81
20270.140.000.80
20280.130.000.80
20290.130.000.79

Western Cattle-Egret Survey Routes in Illinois

Routes recording Western Cattle-Egret 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 →
Sandusky1420091999
Columbia520181987
Jamestown420091982
Bartonville419851985
Pulaski420011970
Beaverdam Lk420111987
St Morgan320041990
Rosamond219721972
Mascoutah Lk220111987
Camp Point119941994
Belleview120242024
Pawnee119801980
Gulfport119931993
Cameron120171998
Olney120002000
Bremen119931993

Western Cattle-Egret Population Trend in Other States

alabamaarizonaarkansascaliforniacoloradodelawarefloridageorgiaidahoindianaiowakansaskentuckylouisianamainemarylandminnesotamississippimissourinebraskanevadanew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomapennsylvaniasouth-carolinasouth-dakotatennesseetexasutahvermontvirginiawisconsinwyoming

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