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Species · California · BBS 2026 Release · 1966–2025

White-breasted Nuthatch Population Trend in California

All statesForest birds

White-breasted Nuthatch in California has risen sharply: up 51% on the route-weighted index since 1970.

+51%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 →
170Routes 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 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 51% 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 rise about 29% by 2030 — from 3.0 in 2025 to a central estimate of 3.9 (95% range 2.7–5.1). A 5-year backtest shows a typical error of ±22.8%, with 80% of held-out values landing inside the 95% band.

+29%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 →
3.9Projected 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 →
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 →
±22.8%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, White-breasted Nuthatch in California is projected to rise about 29% by 2030 — from 3.0 in 2025 to a central estimate of 3.9 (95% range 2.7–5.1). A 5-year backtest shows a typical error of ±22.8%, 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 →
20263.82.64.9
20273.82.65.0
20283.82.75.0
20293.92.75.0
20303.92.75.1

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 →
Carmel Val3220251973
Coyote2720251973
Bass Lake2320191972
Yokohl Val2319971972
Lockwood2320251972
Tres Pinos 22320112005
White River2019921972
Lassen Park1919771972
Tehama1820221973
Jackson1719921974
Yolla Bolly1720251974
Folsom1620251984
Copperopolis1620241975
Red Bluff1520251968
Gold Hill1420251975
Creston1320241976
Angelus Oaks1320171989
Iron Gate1320191988
Little Truckee1320251997
Chilcoot1320241998
Eagle Lake1220251970
Cal Hot Spgs1220191993
Tres Pinos1120031968
Santa Ynez1120191972
Higgins Corn1120251977

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 2026-08-14.