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Species · California · BBS 2026 Release · 1966–2025

Nuttall's Woodpecker Population Trend in California

All statesForest birds

Nuttall's Woodpecker in California has increased: up 48% on the route-weighted index since 1970.

+48%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 →
138Routes 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 Nuttall's Woodpecker 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 Nuttall's Woodpecker in California. See the full index history below.

Nuttall's Woodpecker Population Forecast in California

If the recent trend holds, Nuttall's Woodpecker in California is projected to stay roughly flat through 2030, near 2.2 (95% range 1.6–2.8). A 5-year backtest shows a typical error of ±17.5%, with 80% of held-out values landing inside the 95% band.

+3%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 →
2.2Projected 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 →
1.6–2.895% 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 →
±17.5%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, Nuttall's Woodpecker in California is projected to stay roughly flat through 2030, near 2.2 (95% range 1.6–2.8). A 5-year backtest shows a typical error of ±17.5%, 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 →
20262.21.62.8
20272.21.62.8
20282.21.62.8
20292.21.62.8
20302.21.62.8

Nuttall's Woodpecker Survey Routes in California

Routes recording Nuttall's Woodpecker 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 Val1720251973
Tres Pinos1620031968
Rumsey1520081969
Sisquoc1320141970
Oroville1320251972
Yolla Bolly1320251973
Coyote1320251972
Lake Berryessa1220252023
Mt Laguna1219871970
Elizabeth Lk1220161970
Jackson1219921975
Lockwood1220251972
White River1119921972
Tres Pinos 21120112005
Lake Cachuma1020161972
Auburn919801969
Ono920121984
Adelaida920251970
Poloma920241993
Cuyamaca Pk820251970
Zamora820251980
Santa Ynez720191969
Elsinore Mtn720251970
Jofegan 2620252024
Hughson620251978

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