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

American Robin Population Trend in California

All statesForest birds

American Robin in California has increased: up 33% on the route-weighted index since 1970.

+33%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 →
226Routes 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 American Robin 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 American Robin in California. See the full index history below.

American Robin Population Forecast in California

If the recent trend holds, American Robin in California is projected to rise about 33% by 2029 — from 10 in 2024 to a central estimate of 14 (95% range 9.7–18). A 5-year backtest shows a typical error of ±38.4%, with 20% of held-out values landing inside the 95% band.

+33%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 →
14Projected 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 →
9.7–1895% 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 →
±38.4%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, American Robin in California is projected to rise about 33% by 2029 — from 10 in 2024 to a central estimate of 14 (95% range 9.7–18). A 5-year backtest shows a typical error of ±38.4%, with 20% 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 →
2025149.618
2026149.618
2027149.718
2028149.718
2029149.718

American Robin Survey Routes in California

Routes recording American Robin 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 →
Cottage Spgs6119751968
Collegeville 25520232007
Forest Hill 25220052005
Genesee5220241972
Goumaz5220111997
Eagle Lake5120241969
Point Reyes4620231970
Paxton4520241998
Chester4120171997
Pescadero4020241992
Little Truckee3620231997
Lassen Park3419891972
Gravesboro3319951968
Green Valley3320231970
Crescent Cty3220241972
Rio Dell3220121972
Jackson3219921972
Dorris3220191972
Forest Hill3220221997
Last Chance3220191993
Nubieber3120181970
Crowder Flat3120192002
Hay Fork3120172001
Athlone3020071972
Pennington2920241971

American Robin 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.