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

Lesser Goldfinch Population Trend in Arizona

All statesGeneralists

Lesser Goldfinch in Arizona has surged: up 130% on the route-weighted index since 1970.

+130%Since 1970TrendPercent 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 →
59Routes 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 →
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 Lesser Goldfinch Trends in ArizonaNotable 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 Arizona: up 130% on the route-weighted index since 1970.

Lesser Goldfinch Population Forecast in Arizona

If the recent trend holds, Lesser Goldfinch in Arizona is projected to rise about 69% by 2029 — from 1.6 in 2024 to a central estimate of 2.8 (95% range 1.5–4.0). A 5-year backtest shows a typical error of ±80.7%, with 20% of held-out values landing inside the 95% band.

+69%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 →
2.8Projected 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 →
1.5–4.095% 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 →
±80.7%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, Lesser Goldfinch in Arizona is projected to rise about 69% by 2029 — from 1.6 in 2024 to a central estimate of 2.8 (95% range 1.5–4.0). A 5-year backtest shows a typical error of ±80.7%, with 20% 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 →
20252.61.33.9
20262.61.33.9
20272.71.44.0
20282.71.44.0
20292.81.54.0

Lesser Goldfinch Survey Routes in Arizona

Routes recording Lesser Goldfinch in Arizona.
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 →
Prescott2620221975
Cutter1520141993
Sahuarita1520242006
Oatman1420022002
Pomerene1220241968
Pinetop1020221994
Red Rock 2820192016
Williams820192006
Tonto Vill.820191994
Mormon Lake719741968
Cutter 2720182015
Araby620231998
Redington620231993
Sawmill520141988
Mcneal520171997
Dragoon420071993
Laguna420211968
Patagonia420241968
Ajo 2420182010
The Gap319681968
Palo Verde 2320152015
Skull Valley320241996
Forest Lakes320241994
Bartlett Res320241993
Carr Mtn320241985

Lesser Goldfinch Population Trend in Other States

californiacoloradoidahonevadanew-mexicooregontexasutahwashingtonwyoming

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