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

European Starling Population Trend in California

All statesGeneralists

European Starling in California has increased: up 48% on the route-weighted index since 1970.

+48%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 →
236Routes 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 European Starling 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 European Starling in California. See the full index history below.

European Starling Population Forecast in California

If the recent trend holds, European Starling in California is projected to stay roughly flat through 2030, near 27 (95% range 15–40). A 5-year backtest shows a typical error of ±33.8%, with 80% 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 →
27Projected 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 →
15–4095% 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 →
±33.8%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, European Starling in California is projected to stay roughly flat through 2030, near 27 (95% range 15–40). A 5-year backtest shows a typical error of ±33.8%, with 80% 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 →
2026281540
2027281540
2028281540
2029271540
2030271540

European Starling Survey Routes in California

Routes recording European Starling 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 →
Cedarville36720251974
Westley28520251972
Athlone28120071972
Orland26220221972
Hollister18120111973
Livermore17419911972
Yolla Bolly17320251973
Gravesboro16719951968
Dorris13720191972
Cordova12919811971
Nubieber12720181970
Parkfield12620251968
Tres Pinos 212520112005
Greenfield10420251973
Collegeville 210420232007
Red Bluff10120251968
Palo Verde10120251973
Glenn10020251971
Coulterville10020161997
Santa Cruz I9519881988
South Lake9320062006
Cohasset9020251972
Hughson8320251968
Tipton8219971972
Imperial Dam8120101973

European Starling Population Trend in Other States

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

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