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

American Coot Population Trend in Illinois

All statesWetland birds

American Coot in Illinois has collapsed: down 96% on the route-weighted index since 1971.

-96%Since 1971TrendPercent 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 →
20YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable American Coot 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 →

American Coot has collapsed in Illinois: down 96% on the route-weighted index since 1971.

American Coot Population Forecast in Illinois

If the recent trend holds, American Coot in Illinois is projected to stay roughly flat through 2024, near 0.00 (95% range 0.00–0.35). A 5-year backtest shows a typical error of ±3561.3%, with 20% of held-out values landing inside the 95% band.

n/aChange by 2024TrendPercent 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 →
0.00Projected 2024 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–0.3595% 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 →
±3561.3%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, American Coot in Illinois is projected to stay roughly flat through 2024, near 0.00 (95% range 0.00–0.35). A 5-year backtest shows a typical error of ±3561.3%, with 20% of held-out values landing inside the 95% band.19682024
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 →
20200.000.000.35
20210.000.000.35
20220.000.000.35
20230.000.000.35
20240.000.000.35

American Coot Survey Routes in Illinois

Routes recording American Coot 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 →
Sheffield619731973
New Lenox219841968
Jamestown219761976
Chandlervill219861973
Grape Creek220022002
Belknap220022002
Melrose119761976
Bluff Spgs119751975
Troy Grove120192002
Belleview119761976
Geneseo119881988
Pawnee119721972
Eldred120122012
Newark119841984
Beaucoup119851985
Brnt Prairie120142014

American Coot Population Trend in Other States

alabamaarizonaarkansascaliforniacoloradoconnecticutfloridageorgiaidahoindianaiowakansaskentuckylouisianamichiganminnesotamississippimissourimontananebraskanevadanew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniasouth-dakotatennesseetexasutahvermontwashingtonwest-virginiawisconsinwyoming

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