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

Red-tailed Hawk Population Trend in California

All statesBirds of prey

Red-tailed Hawk in California has increased: up 36% on the route-weighted index since 1970.

+36%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 →
260Routes 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 Red-tailed Hawk 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 Red-tailed Hawk in California. See the full index history below.

Red-tailed Hawk Population Forecast in California

If the recent trend holds, Red-tailed Hawk in California is projected to stay roughly flat through 2030, near 3.8 (95% range 3.1–4.5). A 5-year backtest shows a typical error of ±11.6%, with 80% of held-out values landing inside the 95% band.

+5%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 →
3.8Projected 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 →
3.1–4.595% 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 →
±11.6%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, Red-tailed Hawk in California is projected to stay roughly flat through 2030, near 3.8 (95% range 3.1–4.5). A 5-year backtest shows a typical error of ±11.6%, 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 →
20263.73.04.4
20273.73.04.4
20283.83.14.5
20293.83.14.5
20303.83.14.5

Red-tailed Hawk Survey Routes in California

Routes recording Red-tailed Hawk 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 →
Athlone3320071972
Dorris2920191972
Adelaida2820251970
Macdoel2520191972
Parkfield2220251968
Tres Pinos 22020112005
Hughson1920251968
Oneals1820241972
Hollister1420111974
Sanger1420242011
Likely1420251971
Ventucopa1220021975
Moraga1220251972
Copperopolis1220241972
Ora Loma1220251973
Sisquoc1120141970
Cedarville1120251974
Collegeville 21120232007
Moreno920251968
Atwater920121971
Livermore919911972
Goumaz920111997
Oak Grove820251969
Mesa Grande820251970
Carmel Val820251973

Red-tailed Hawk Population Trend in Other States

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

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