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

Great Egret Population Trend in California

All statesWetland birds

Great Egret in California has surged: up 40× on the route-weighted index since 1971.

40×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 →
81Routes 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 →
56YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Great Egret 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 Great Egret in California. See the full index history below.

Great Egret Population Forecast in California

If the recent trend holds, Great Egret in California is projected to rise about 51% by 2030 — from 1.4 in 2025 to a central estimate of 2.0 (95% range 0.73–3.4). A 5-year backtest shows a typical error of ±86.1%, with 80% of held-out values landing inside the 95% band.

+51%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 →
2.0Projected 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 →
0.73–3.495% 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 →
±86.1%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 →
If the recent trend holds, Great Egret in California is projected to rise about 51% by 2030 — from 1.4 in 2025 to a central estimate of 2.0 (95% range 0.73–3.4). A 5-year backtest shows a typical error of ±86.1%, 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 →
20262.00.663.3
20272.00.683.3
20282.00.703.3
20292.00.713.3
20302.00.733.4

Great Egret Survey Routes in California

Routes recording Great Egret 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 →
Glenn6220251971
Dorris4420191973
Hughson1720241968
Brawley1320121984
Zamora1220251982
Atwater1120121982
Collegeville 21120232007
Fairfax820241972
Buena Vista820191995
Athlone720072003
Sisquoc620002000
Tranquillity620231972
Pennington520251978
Jofegan 2420252024
Palo Verde420251973
Orland420191984
Havasu Lake419731973
Oroville420251976
Clear Lk Res419991984
Staten Is.420251994
Tracy 2420152015
Niland320251973
Poway319771977
Westley320251975
Macdoel320181986

Great Egret Population Trend in Other States

alabamaarizonaarkansascoloradoconnecticutdelawarefloridageorgiaidahoillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanevadanew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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