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Species · California · BBS 2026 Release · 1966–2025

Golden-crowned Kinglet Population Trend in California

All statesForest birds

Golden-crowned Kinglet in California has surged: up 669% on the route-weighted index since 1970.

+669%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 →
95Routes 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 Golden-crowned Kinglet 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 →

long arc increasecomputed 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 →

Golden-crowned Kinglet has surged in California: up 669% on the route-weighted index since 1970.

Golden-crowned Kinglet Population Forecast in California

If the recent trend holds, Golden-crowned Kinglet in California is projected to rise about 63% by 2030 — from 1.5 in 2025 to a central estimate of 2.4 (95% range 1.4–3.4). A 5-year backtest shows a typical error of ±120.7%, with 0% of held-out values landing inside the 95% band.

+63%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 →
2.4Projected 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 →
1.4–3.495% 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 →
±120.7%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, Golden-crowned Kinglet in California is projected to rise about 63% by 2030 — from 1.5 in 2025 to a central estimate of 2.4 (95% range 1.4–3.4). A 5-year backtest shows a typical error of ±120.7%, with 0% 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 →
20262.31.33.3
20272.31.33.3
20282.41.33.4
20292.41.43.4
20302.41.43.4

Golden-crowned Kinglet Survey Routes in California

Routes recording Golden-crowned Kinglet 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 →
Offield Mtn3420141980
Lumberyard3120251976
Chester2620171997
Riverton2420251975
Redwood N.P. 22420132012
Pilot Creek2219961994
Butte Meadow2120141972
Crescent Cty1320251972
Greenhorn Mt1320081971
Genesee1220191973
Last Chance1120191994
Holmes1020251968
Westville1020251971
Tahoe Nf1019941987
Laytonville820251974
Lassen Park719881978
Alderpoint720121980
Point Reyes620251980
Martins Fy620091976
Silver City620131978
Tuolumne Grove620251972
Gazelle620042001
Little Truckee620191997
Horse Creek519901990
Woodfords520251975

Golden-crowned Kinglet Population Trend in Other States

alaskaarizonacoloradoconnecticutgeorgiaidahomainemarylandmassachusettsmichiganminnesotamontananevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinaohiooregonpennsylvaniasouth-dakotatennesseeutahvermontwashingtonwest-virginiawisconsinwyoming

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