BirdAnalyst
Species · BCR 15 · BBS 2026 Release · 1966–2025

Red-breasted Nuthatch In Sierra Nevada

All regionsSierra NevadaForest birds

Red-breasted Nuthatch in Sierra Nevada has risen sharply: up 55% on the route-weighted index since 1970.

+55%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 →
39Routes 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 →
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 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 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 →

Red-breasted Nuthatch has risen sharply in Sierra Nevada: up 55% on the route-weighted index since 1970.

Red-breasted Nuthatch In Sierra Nevada Population Forecast

If the recent trend holds, Red-breasted Nuthatch in Sierra Nevada is projected to rise about 16% by 2030 — from 15 in 2025 to a central estimate of 17 (95% range 8.9–25). A 5-year backtest shows a typical error of ±12.3%, with 100% of held-out values landing inside the 95% band.

+16%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 →
17Projected 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 →
8.9–2595% 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 →
±12.3%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-breasted Nuthatch in Sierra Nevada is projected to rise about 16% by 2030 — from 15 in 2025 to a central estimate of 17 (95% range 8.9–25). A 5-year backtest shows a typical error of ±12.3%, with 100% 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 →
2026178.625
2027178.725
2028178.825
2029178.925
2030178.925

Routes In Sierra Nevada

Routes recording Red-breasted Nuthatch 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 →
Lassen ParkCALIFORNIA471989
RivertonCALIFORNIA422025
GoumazCALIFORNIA372011
WestvilleCALIFORNIA362025
Hat CreekCALIFORNIA342018
Little TruckeeCALIFORNIA282025
LumberyardCALIFORNIA272025
Meadow ValleyCALIFORNIA242025
StrawberryCALIFORNIA242019
Forest Hill 2CALIFORNIA232005
ChesterCALIFORNIA222017
JohnsvilleCALIFORNIA212025
Butte MeadowCALIFORNIA212014
Greenhorn MtCALIFORNIA202008
DownievilleCALIFORNIA162025
Tahoe NfCALIFORNIA161994
Tuolumne GroveCALIFORNIA152025
Pine MountainCALIFORNIA132017
Forest HillCALIFORNIA112025
Eagle LakeCALIFORNIA102025
GeneseeCALIFORNIA102024
Cottage SpgsCALIFORNIA91975
Pollock PinesCALIFORNIA92025
PlacervilleCALIFORNIA92025
Silver CityCALIFORNIA82013

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