BirdAnalyst
Species · California · BBS 2026 Release · 1966–2025

American Coot Population Trend in California

All statesWetland birds

American Coot in California has edged up: up 16% on the route-weighted index since 1970.

+16%Since 1970TrendPercent 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 →
125Routes 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 American Coot Trends in CaliforniaNotable 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 American Coot in California. See the full index history below.

American Coot Population Forecast in California

If the recent trend holds, American Coot in California is projected to rise about 227% by 2030 — from 0.65 in 2025 to a central estimate of 2.1 (95% range 0.00–6.3). A 5-year backtest shows a typical error of ±920.4%, with 100% of held-out values landing inside the 95% band.

+227%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 →
2.1Projected 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 →
0.00–6.395% 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 →
±920.4%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 California is projected to rise about 227% by 2030 — from 0.65 in 2025 to a central estimate of 2.1 (95% range 0.00–6.3). A 5-year backtest shows a typical error of ±920.4%, with 100% of held-out values landing inside the 95% band.19682030
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 →
20262.10.006.3
20272.10.006.3
20282.10.006.3
20292.10.006.3
20302.10.006.3

American Coot Survey Routes in California

Routes recording American Coot in California.
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 →
Dorris23020191972
Carrizo Pln8819781978
Cp. Pendleton4519911972
Likely2020251979
Big Bear1619861969
Coyote1320251972
Athlone1019891982
Collegeville819871972
Green Valley820122012
Ventucopa719971992
Glenn720151971
Crowder Flat720192002
Mesa Grande620051999
Jofegan 2520252025
Pearblossom520252025
Clear Lk Res519901984
Pescadero520241992
Poloma520231993
Rumsey419881988
Tres Pinos420021996
Foster Park419941968
Lake Hemet419811981
Laytonville419901990
Mark West419781976
Copperopolis420181979

American Coot Population Trend in Other States

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