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

Pygmy Nuthatch Population Trend in Utah

All statesForest birds

Pygmy Nuthatch in Utah has fallen sharply: down 71% on the route-weighted index since 1992.

-71%Since 1992TrendPercent 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 →
7Routes 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 →
30YearsYears 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 UtahNotable 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 Utah: down 71% on the route-weighted index since 1992.

Pygmy Nuthatch Population Forecast in Utah

If the recent trend holds, Pygmy Nuthatch in Utah is projected to fall about 62% by 2029 — from 0.10 in 2024 to a central estimate of 0.04 (95% range 0.00–0.41). A 5-year backtest shows a typical error of ±49.1%, with 100% of held-out values landing inside the 95% band.

-62%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 →
0.04Projected 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 →
0.00–0.4195% 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 →
±49.1%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, Pygmy Nuthatch in Utah is projected to fall about 62% by 2029 — from 0.10 in 2024 to a central estimate of 0.04 (95% range 0.00–0.41). A 5-year backtest shows a typical error of ±49.1%, 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 →
20250.070.000.44
20260.060.000.43
20270.050.000.42
20280.050.000.41
20290.040.000.41

Pygmy Nuthatch Survey Routes in Utah

Routes recording Pygmy Nuthatch in Utah.
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 →
Navajo Lake619681968
Bryce Canyon520241990
La Sal420001999
M Warner Res320232022
Alton220022002
La Sal 2220062004
Dixie Nf120241993

Pygmy Nuthatch Population Trend in Other States

arizonacaliforniacoloradoidahomontananebraskanew-mexicooregonsouth-dakotawashingtonwyoming

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