BirdAnalyst
Species · Idaho · BBS 2026 Release · 1966–2025

Lesser Goldfinch Population Trend in Idaho

All statesForest birds

Lesser Goldfinch in Idaho has surged: up 99% on the route-weighted index since 2007.

+99%Since 2007TrendPercent 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 →
8Routes 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 →
19YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Lesser Goldfinch 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 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 →

Lesser Goldfinch has surged in Idaho: up 99% on the route-weighted index since 2007.

Lesser Goldfinch Population Forecast in Idaho

If the recent trend holds, Lesser Goldfinch in Idaho is projected to rise about 688% by 2030 — from 0.06 in 2025 to a central estimate of 0.45 (95% range 0.00–1.2). A 5-year backtest shows a typical error of ±998.2%, with 40% of held-out values landing inside the 95% band.

+688%Change by 2030TrendPercent 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 →
0.45Projected 2030 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–1.295% 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 →
±998.2%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, Lesser Goldfinch in Idaho is projected to rise about 688% by 2030 — from 0.06 in 2025 to a central estimate of 0.45 (95% range 0.00–1.2). A 5-year backtest shows a typical error of ±998.2%, with 40% of held-out values landing inside the 95% band.19982030
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 →
20260.420.001.2
20270.430.001.2
20280.430.001.2
20290.440.001.2
20300.450.001.2

Lesser Goldfinch Survey Routes in Idaho

Routes recording Lesser Goldfinch 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 →
Gifford5020172006
Pocatello720192019
Joel420242010
Picabo220252025
Dougal Res220112007
Cedar Hill119981998
Circular Bu120232023
Magic Mtn120242016

Lesser Goldfinch Population Trend in Other States

arizonacaliforniacoloradonevadanew-mexicooregontexasutahwashingtonwyoming

Source: USGS North American Breeding Bird Survey, retrieved 2026-08-14.