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Species · California · BBS 2025 Release · 1966–2024

White-breasted Nuthatch Population Trend in California

All statesForest birds

White-breasted Nuthatch in California has risen sharply: up 66% on the route-weighted index since 1970.

+66%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 →
169Routes 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 White-breasted Nuthatch 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 →

White-breasted Nuthatch has risen sharply in California: up 65% on the route-weighted index since 1970.

White-breasted Nuthatch Population Forecast in California

If the recent trend holds, White-breasted Nuthatch in California is projected to stay roughly flat through 2029, near 3.9 (95% range 2.7–5.1). A 5-year backtest shows a typical error of ±21.9%, with 80% of held-out values landing inside the 95% band.

+8%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 →
3.9Projected 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 →
2.7–5.195% 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 →
±21.9%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, White-breasted Nuthatch in California is projected to stay roughly flat through 2029, near 3.9 (95% range 2.7–5.1). A 5-year backtest shows a typical error of ±21.9%, with 80% 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 →
20253.82.65.0
20263.82.75.0
20273.92.75.0
20283.92.75.1
20293.92.75.1

White-breasted Nuthatch Survey Routes in California

Routes recording White-breasted Nuthatch 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 →
Gold Hill3020241975
Lockwood2420241972
Bass Lake2320191972
Yokohl Val2319971972
Tres Pinos 22320112005
Yolla Bolly2220241974
White River2019921972
Lassen Park1919771972
Lake Berryessa1920242023
Adelaida1820241970
Tehama1820221973
Jackson1719921974
Copperopolis1620241975
Moraga1520241978
Coyote1420241973
Folsom1320241984
Creston1320241976
Angelus Oaks1320171989
Iron Gate1320191988
Chilcoot1320241998
Cal Hot Spgs1220191993
Tres Pinos1120031968
Santa Ynez1120191972
Crowder Flat1120192002
Orange Cove1020161972

White-breasted Nuthatch Population Trend in Other States

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

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