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

Red-breasted Nuthatch In Sierra Nevada

All regionsSierra NevadaForest birds

Red-breasted Nuthatch in Sierra Nevada has risen sharply: up 61% on the route-weighted index since 1970.

+61%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 →
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 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 61% 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 2029 — from 15 in 2024 to a central estimate of 17 (95% range 9.0–25). A 5-year backtest shows a typical error of ±11.6%, with 100% of held-out values landing inside the 95% band.

+16%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 →
17Projected 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 →
9.0–2595% 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 →
±11.6%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, Red-breasted Nuthatch in Sierra Nevada is projected to rise about 16% by 2029 — from 15 in 2024 to a central estimate of 17 (95% range 9.0–25). A 5-year backtest shows a typical error of ±11.6%, with 100% 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 →
2025178.625
2026178.725
2027178.825
2028178.925
2029179.025

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 →
LumberyardCALIFORNIA742024
Lassen ParkCALIFORNIA471989
WestvilleCALIFORNIA472024
GoumazCALIFORNIA372011
Hat CreekCALIFORNIA342018
Meadow ValleyCALIFORNIA282024
PlacervilleCALIFORNIA262024
Forest HillCALIFORNIA242022
StrawberryCALIFORNIA242019
RivertonCALIFORNIA232023
Forest Hill 2CALIFORNIA232005
ChesterCALIFORNIA222017
Butte MeadowCALIFORNIA212014
DownievilleCALIFORNIA212024
JohnsvilleCALIFORNIA202024
Greenhorn MtCALIFORNIA202008
Little TruckeeCALIFORNIA172023
Tahoe NfCALIFORNIA161994
Tuolumne GroveCALIFORNIA152024
Pollock PinesCALIFORNIA152024
Pine MountainCALIFORNIA132017
GeneseeCALIFORNIA102024
Cottage SpgsCALIFORNIA91975
Silver CityCALIFORNIA82013
SattleyCALIFORNIA72019

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