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

Purple Finch In Northern Rockies

All regionsNorthern RockiesGeneralists

Purple Finch in Northern Rockies has collapsed: down 79% on the route-weighted index since 1987.

-79%Since 1987TrendPercent 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 →
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 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 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 →

Purple Finch has collapsed in Northern Rockies: down 79% on the route-weighted index since 1987.

Purple Finch In Northern Rockies Population Forecast

If the recent trend holds, Purple Finch in Northern Rockies is projected to stay roughly flat through 2022, near 0.00 (95% range 0.00–0.18). A 5-year backtest shows a typical error of ±149.4%, with 100% of held-out values landing inside the 95% band.

n/aChange by 2022TrendPercent 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 →
0.00Projected 2022 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–0.1895% 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 →
±149.4%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, Purple Finch in Northern Rockies is projected to stay roughly flat through 2022, near 0.00 (95% range 0.00–0.18). A 5-year backtest shows a typical error of ±149.4%, with 100% of held-out values landing inside the 95% band.19732022
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 →
20180.000.000.18
20190.000.000.18
20200.000.000.18
20210.000.000.18
20220.000.000.18

Routes In Northern Rockies

Routes recording Purple Finch 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 →
GraniteOREGON301989
DesolationOREGON51993
Summit PrOREGON42013
OchocoOREGON31976
Mount VernonOREGON22016
Omak CreekWASHINGTON22007
AlbeeOREGON12014
LogdellOREGON12017
WickiupOREGON11996
Silver CreekOREGON12008
Hells CanyonOREGON11998

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