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Species · BCR 15 · BBS 2025 Release · 1966–2024

Nuttall's Woodpecker In Sierra Nevada

All regionsSierra NevadaForest birds

Nuttall's Woodpecker in Sierra Nevada has collapsed: down 80% on the route-weighted index since 1973.

-80%Since 1973TrendPercent 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 →
14Routes In RegionSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
53YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable SignalsNotable 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 declinecomputed 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 →

Nuttall's Woodpecker has collapsed in Sierra Nevada: down 80% on the route-weighted index since 1973.

Nuttall's Woodpecker In Sierra Nevada Population Forecast

If the recent trend holds, Nuttall's Woodpecker in Sierra Nevada is projected to rise about 29% by 2029 — from 0.32 in 2024 to a central estimate of 0.41 (95% range 0.00–1.0). A 5-year backtest shows a typical error of ±131.6%, with 100% of held-out values landing inside the 95% band.

+29%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 →
0.41Projected 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 →
0.00–1.095% 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 →
±131.6%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, Nuttall's Woodpecker in Sierra Nevada is projected to rise about 29% by 2029 — from 0.32 in 2024 to a central estimate of 0.41 (95% range 0.00–1.0). A 5-year backtest shows a typical error of ±131.6%, with 100% of held-out values landing inside the 95% band.19702029
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 →
20250.410.001.0
20260.410.001.0
20270.410.001.0
20280.410.001.0
20290.410.001.0

Routes In Sierra Nevada

Routes recording Nuttall's Woodpecker in Sierra Nevada.
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 →
Silver CityCALIFORNIA52013
Cottage SpgsCALIFORNIA41970
Bass LakeCALIFORNIA32019
Kings CanyonCALIFORNIA32024
Forest Hill 2CALIFORNIA22005
Lassen ParkCALIFORNIA11985
Greenhorn MtCALIFORNIA12006
Tuolumne GroveCALIFORNIA12024
GeneseeCALIFORNIA11972
Higgins CornCALIFORNIA12024
LakeshoreCALIFORNIA11973
CoultervilleCALIFORNIA12017
WawonaCALIFORNIA12024
Pine MountainCALIFORNIA11998

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