BirdAnalyst
Species · California · BBS 2025 Release · 1966–2024

Western Kingbird Population Trend in California

All statesAerial insectivores

Western Kingbird 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 →
219Routes 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 Western Kingbird 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 Western Kingbird in California. See the full index history below.

Western Kingbird Population Forecast in California

If the recent trend holds, Western Kingbird in California is projected to rise about 11% by 2029 — from 7.5 in 2024 to a central estimate of 8.4 (95% range 5.6–11). A 5-year backtest shows a typical error of ±19.1%, with 100% of held-out values landing inside the 95% band.

+11%Change by 2029TrendPercent 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 →
8.4Projected 2029 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
5.6–1195% 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 →
±19.1%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, Western Kingbird in California is projected to rise about 11% by 2029 — from 7.5 in 2024 to a central estimate of 8.4 (95% range 5.6–11). A 5-year backtest shows a typical error of ±19.1%, with 100% of held-out values landing inside the 95% band.19682029
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 →
20258.55.711
20268.45.711
20278.45.711
20288.45.711
20298.45.611

Western Kingbird Survey Routes in California

Routes recording Western Kingbird 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 →
Athlone13020071972
Orland7520221972
Tranquillity6520241972
Atwater6220121971
Ora Loma5120241972
Oneals5020241972
Redding4619831972
Tres Pinos 24620112005
Zamora4520241972
Iron Gate4220191988
Tipton4019971972
Hughson3920241968
Yokohl Val3619971972
Tracy3520091992
Shafter3419891971
Bakersfield3320231968
Jackson3019921972
Tres Pinos2620031968
Parkfield2620241968
Ventucopa2620021972
Imperial Dam2520101973
Westley2520241972
Buena Vista2420191990
Cohasset2320241972
Yolla Bolly2320241973

Western Kingbird Population Trend in Other States

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Source: USGS North American Breeding Bird Survey, retrieved 2026-05-22.