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Species · Idaho · BBS 2025 Release · 1966–2024

Pygmy Nuthatch Population Trend in Idaho

All statesForest birds

Pygmy Nuthatch in Idaho has fallen sharply: down 75% on the route-weighted index since 1989.

-75%Since 1989TrendPercent 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 →
6Routes 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 →
27YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Pygmy Nuthatch Trends in IdahoNotable 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 →

Pygmy Nuthatch has fallen sharply in Idaho: down 75% on the route-weighted index since 1989.

Pygmy Nuthatch Population Forecast in Idaho

If the recent trend holds, Pygmy Nuthatch in Idaho is projected to stay roughly flat through 2029, near 0.01 (95% range 0.00–0.13). A 5-year backtest shows a typical error of ±75.7%, with 100% of held-out values landing inside the 95% band.

n/aChange 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 →
0.01Projected 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 →
0.00–0.1395% 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 →
±75.7%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, Pygmy Nuthatch in Idaho is projected to stay roughly flat through 2029, near 0.01 (95% range 0.00–0.13). A 5-year backtest shows a typical error of ±75.7%, 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 →
20250.020.000.14
20260.020.000.14
20270.010.000.13
20280.010.000.13
20290.010.000.13

Pygmy Nuthatch Survey Routes in Idaho

Routes recording Pygmy Nuthatch in Idaho.
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 →
Salmon River320212021
Alturas219681968
Featherville220052000
Gifford120171986
Joel120241989
Coolin120151995

Pygmy Nuthatch Population Trend in Other States

arizonacaliforniacoloradomontananebraskanew-mexicooregonsouth-dakotautahwashingtonwyoming

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