BirdAnalyst
Species · Pennsylvania · BBS 2025 Release · 1966–2024

Red-breasted Nuthatch Population Trend in Pennsylvania

All statesForest birds

Red-breasted Nuthatch in Pennsylvania has surged: up 269% on the route-weighted index since 1974.

+269%Since 1974TrendPercent 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 →
56Routes 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 →
44YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Red-breasted Nuthatch Trends in PennsylvaniaNotable 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 surged in Pennsylvania: up 269% on the route-weighted index since 1974.

Red-breasted Nuthatch Population Forecast in Pennsylvania

If the recent trend holds, Red-breasted Nuthatch in Pennsylvania is projected to fall about 17% by 2029 — from 0.15 in 2024 to a central estimate of 0.12 (95% range 0.03–0.21). A 5-year backtest shows a typical error of ±45.7%, with 100% of held-out values landing inside the 95% band.

-17%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 →
0.12Projected 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 →
0.03–0.2195% 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 →
±45.7%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 Pennsylvania is projected to fall about 17% by 2029 — from 0.15 in 2024 to a central estimate of 0.12 (95% range 0.03–0.21). A 5-year backtest shows a typical error of ±45.7%, with 100% of held-out values landing inside the 95% band.19722029
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 →
20250.110.020.20
20260.120.030.21
20270.120.030.21
20280.120.030.21
20290.120.030.21

Red-breasted Nuthatch Survey Routes in Pennsylvania

Routes recording Red-breasted Nuthatch in Pennsylvania.
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 →
Patton319831983
Teepleville220221998
Eldred220152007
Cherry Sprs220191981
Bow Bridge220101999
Marsh Hill220231990
Pine Gr Mill220181998
Sproul Sf-A220232010
Sugar Grove220092009
Ellenton120052002
Whig Hill120231990
Berwick120221987
Sigel120242024
Lynch120221998
N Washington120192003
N Pine Grove120232006
Pottersdale120131973
Odin120241993
Betula120072003
Russell City120222007
Ridgway120162016
Rasselas120211996
Roulette120132007
Ansonia120242002
Arnot120241996

Red-breasted Nuthatch Population Trend in Other States

alaskaarizonacaliforniacoloradoconnecticutidahoillinoisindianakansasmainemarylandmassachusettsmichiganminnesotamontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooregonrhode-islandsouth-carolinasouth-dakotatennesseeutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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