BirdAnalyst
Species · BCR 32 · BBS 2025 Release · 1966–2024

Red-breasted Nuthatch In Coastal California

All regionsCoastal CaliforniaForest birds

Red-breasted Nuthatch in Coastal California has risen sharply: up 55% on the route-weighted index since 1972.

+55%Since 1972TrendPercent 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 →
42Routes 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 →
54YearsYears 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 Coastal California: up 55% on the route-weighted index since 1972.

Red-breasted Nuthatch In Coastal California Population Forecast

If the recent trend holds, Red-breasted Nuthatch in Coastal California is projected to rise about 57% by 2029 — from 0.47 in 2024 to a central estimate of 0.74 (95% range 0.33–1.1). A 5-year backtest shows a typical error of ±82.1%, with 80% of held-out values landing inside the 95% band.

+57%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 →
0.74Projected 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 →
0.33–1.195% 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 →
±82.1%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 Coastal California is projected to rise about 57% by 2029 — from 0.47 in 2024 to a central estimate of 0.74 (95% range 0.33–1.1). A 5-year backtest shows a typical error of ±82.1%, with 80% of held-out values landing inside the 95% band.19692029
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 →
20250.710.301.1
20260.710.311.1
20270.720.321.1
20280.730.331.1
20290.740.331.1

Routes In Coastal California

Routes recording Red-breasted Nuthatch in Coastal 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 →
Lake Hemet 2CALIFORNIA261993
StonyfordCALIFORNIA242018
Hough SpringsCALIFORNIA152007
FairfaxCALIFORNIA132024
Bartlett SpsCALIFORNIA112018
CohassetCALIFORNIA72024
AdelaidaCALIFORNIA71975
TomheadCALIFORNIA62011
TehamaCALIFORNIA52022
White RiverCALIFORNIA41992
FolsomCALIFORNIA31995
ValyermoCALIFORNIA32019
Mt Pinos 2CALIFORNIA32021
Yolla BollyCALIFORNIA31973
Angelus OaksCALIFORNIA32014
CalpellaCALIFORNIA21982
Point ReyesCALIFORNIA22011
Mt LagunaCALIFORNIA21971
Green ValleyCALIFORNIA22022
MoragaCALIFORNIA22024
Red BluffCALIFORNIA11991
ColmaCALIFORNIA11972
Yokohl ValCALIFORNIA11993
ParkfieldCALIFORNIA12008
Mt PinosCALIFORNIA11993

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