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

Purple Finch Population Trend in Oregon

All statesForest birds

Purple Finch in Oregon has collapsed: down 80% on the route-weighted index since 1970.

-80%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 →
82Routes 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 →
57YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Purple Finch Trends in OregonNotable 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 Oregon: down 80% on the route-weighted index since 1970.

Purple Finch Population Forecast in Oregon

If the recent trend holds, Purple Finch in Oregon is projected to fall about 63% by 2030 — from 1.3 in 2025 to a central estimate of 0.47 (95% range 0.00–2.4). A 5-year backtest shows a typical error of ±60.1%, with 100% of held-out values landing inside the 95% band.

-63%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 →
0.47Projected 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 →
0.00–2.495% 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 →
±60.1%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, Purple Finch in Oregon is projected to fall about 63% by 2030 — from 1.3 in 2025 to a central estimate of 0.47 (95% range 0.00–2.4). A 5-year backtest shows a typical error of ±60.1%, with 100% of held-out values landing inside the 95% band.19682030
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 →
20260.640.002.5
20270.600.002.5
20280.560.002.4
20290.520.002.4
20300.470.002.4

Purple Finch Survey Routes in Oregon

Routes recording Purple Finch in Oregon.
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 →
Granite3019891989
Lorane1520251993
Hauser1119851970
Dayton1120251973
Badger Creek1120251992
Lobster Creek1020252025
Nicolai Mtn.920251993
Scio820251975
Glasgow820251986
Wizard Falls720222018
Coquille720251994
Adair620251971
Mt Hood620251972
Salem620251993
Sandy River620061993
Tualatin520251969
Secret Val520251975
Desolation519931993
Garfield420251974
Svensen419921990
Summit Pr420132009
Klickitat Mt419961993
Prospect420241993
Riley Peak420161994
Harlan 2420252016

Purple Finch Population Trend in Other States

alaskacaliforniaconnecticutindianamainemarylandmassachusettsmichiganminnesotanew-hampshirenew-jerseynew-yorknorth-dakotaohiopennsylvaniarhode-islandvermontwashingtonwest-virginiawisconsin

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