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

Common Yellowthroat Population Trend in California

All statesForest birds

Common Yellowthroat in California has surged: up 922% on the route-weighted index since 1970.

+922%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 →
123Routes 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 Common Yellowthroat 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 →

Common Yellowthroat has surged in California: up 922% on the route-weighted index since 1970.

Common Yellowthroat Population Forecast in California

If the recent trend holds, Common Yellowthroat in California is projected to fall about 26% by 2029 — from 1.2 in 2024 to a central estimate of 0.89 (95% range 0.33–1.5). A 5-year backtest shows a typical error of ±28.8%, with 100% of held-out values landing inside the 95% band.

-26%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 →
0.89Projected 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 →
0.33–1.595% 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 →
±28.8%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, Common Yellowthroat in California is projected to fall about 26% by 2029 — from 1.2 in 2024 to a central estimate of 0.89 (95% range 0.33–1.5). A 5-year backtest shows a typical error of ±28.8%, 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 →
20250.860.291.4
20260.860.301.4
20270.880.311.4
20280.880.321.4
20290.890.331.5

Common Yellowthroat Survey Routes in California

Routes recording Common Yellowthroat 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 →
Jofegan 22720242024
Ora Loma1720241995
Alamo River1520181973
Cp. Pendleton1520041972
Imperial Dam1220101973
Dorris1020191975
Palo Verde920241973
Staten Is.920241994
Navarro719921991
Poway719801974
South Lake720062006
Moreno620241985
Niland620241973
Jofegan620232006
Harbor Lake 2620242014
Foster Park519941972
San Ysidro520191973
Point Reyes520231970
Athlone519791975
Glamis419771974
Blythe419791973
Fairfax320241985
El Toro319991980
Cuyamaca Pk320242017
Elizabeth Lk320161981

Common Yellowthroat Population Trend in Other States

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

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