BirdAnalyst
Species · BCR 10 · BBS 2025 Release · 1966–2024

Lesser Goldfinch In Northern Rockies

All regionsNorthern RockiesGeneralists

Lesser Goldfinch in Northern Rockies has surged: up 395% on the route-weighted index since 2005.

+395%Since 2005TrendPercent 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 →
11Routes In RegionSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
21YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable SignalsNotable 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 Northern Rockies: up 395% on the route-weighted index since 2005.

Lesser Goldfinch In Northern Rockies Population Forecast

If the recent trend holds, Lesser Goldfinch in Northern Rockies is projected to fall about 35% by 2029 — from 0.11 in 2024 to a central estimate of 0.07 (95% range 0.01–0.13). A 5-year backtest shows a typical error of ±75.6%, with 20% of held-out values landing inside the 95% band.

-35%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 →
0.07Projected 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 →
0.01–0.1395% 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 →
±75.6%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 Northern Rockies is projected to fall about 35% by 2029 — from 0.11 in 2024 to a central estimate of 0.07 (95% range 0.01–0.13). A 5-year backtest shows a typical error of ±75.6%, with 20% of held-out values landing inside the 95% band.19842029
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 →
20250.060.010.12
20260.060.010.12
20270.070.010.12
20280.070.010.12
20290.070.010.13

Routes In Northern Rockies

Routes recording Lesser Goldfinch in Northern Rockies.
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 →
TwickenhamOREGON62024
MonumentOREGON52024
MadrasOREGON32024
MeeteetseWYOMING32018
WoodruffUTAH22023
Mtn ViewWYOMING22016
Browns ParkCOLORADO11993
Summit PrOREGON11984
NewbridgeOREGON12024
WalcottWYOMING12017
SeedskadeeWYOMING12023

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