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

American Goldfinch Population Trend in California

All statesForest birds

American Goldfinch in California has held roughly steady: up 7% on the route-weighted index since 1970.

+7%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 →
148Routes 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 Goldfinch 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 Goldfinch in California. See the full index history below.

American Goldfinch Population Forecast in California

If the recent trend holds, American Goldfinch in California is projected to stay roughly flat through 2030, near 2.3 (95% range 0.90–3.7). A 5-year backtest shows a typical error of ±50.8%, with 100% of held-out values landing inside the 95% band.

+5%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 →
2.3Projected 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 →
0.90–3.795% 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 →
±50.8%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 Goldfinch in California is projected to stay roughly flat through 2030, near 2.3 (95% range 0.90–3.7). A 5-year backtest shows a typical error of ±50.8%, 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 →
20262.30.863.7
20272.30.873.7
20282.30.883.7
20292.30.893.7
20302.30.903.7

American Goldfinch Survey Routes in California

Routes recording American Goldfinch 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 →
Lake Success4219781972
Zamora3820251975
Collegeville 23120232007
Cohasset2920251972
Oroville2820251972
Honeydew2220171968
Rio Dell2220121972
Westley2020251976
Crescent Cty1920251972
Atwater1620122003
Dorris1520192001
Cp. Pendleton1320041971
Ora Loma1320251981
Fish Rock1220141968
Redwood N.P.1220101995
Tres Pinos1019961973
Mt Laguna1019861974
Hughson920251968
Lake Hemet 2919931992
Pennington820251971
Auburn819801969
Lockwood Val820082008
Cuyamaca Pk819751973
Greenhorn Mt719801974
Mark West720251975

American Goldfinch Population Trend in Other States

alabamaarkansascoloradoconnecticutdelawaregeorgiaidahoillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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