BirdAnalyst
Species · BCR 9 · BBS 2025 Release · 1966–2024

Purple Finch In Great Basin

All regionsGreat BasinGeneralists

Purple Finch in Great Basin has increased: up 41% on the route-weighted index since 1970.

+41%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 →
57Routes 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 →
56YearsYears 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 →

No notable trend signals for Purple Finch in Great Basin. See the full index history below.

Purple Finch In Great Basin Population Forecast

If the recent trend holds, Purple Finch in Great Basin is projected to fall about 44% by 2029 — from 0.70 in 2024 to a central estimate of 0.39 (95% range 0.00–0.99). A 5-year backtest shows a typical error of ±35.5%, with 100% of held-out values landing inside the 95% band.

-44%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 →
0.39Projected 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 →
0.00–0.9995% 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 →
±35.5%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 Great Basin is projected to fall about 44% by 2029 — from 0.70 in 2024 to a central estimate of 0.39 (95% range 0.00–0.99). A 5-year backtest shows a typical error of ±35.5%, with 100% 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 →
20250.410.001.0
20260.400.001.0
20270.400.001.0
20280.400.001.00
20290.390.000.99

Routes In Great Basin

Routes recording Purple Finch in Great Basin.
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 →
LeavenworthWASHINGTON172024
KendallWASHINGTON132024
ArdenvoirWASHINGTON111972
L. WenatcheeWASHINGTON112024
MazamaWASHINGTON102022
Crowley LakeCALIFORNIA91977
Mt HoodOREGON92024
Badger CreekOREGON92024
Crowder FlatCALIFORNIA82002
Blewett PassWASHINGTON82024
NubieberCALIFORNIA72007
Wizard FallsOREGON72022
TwispWASHINGTON72024
WinthropWASHINGTON72010
RimrockWASHINGTON62024
LikelyCALIFORNIA51978
Davis CreekCALIFORNIA51979
MacdoelCALIFORNIA42016
RonaldWASHINGTON42024
Lake ChelanWASHINGTON42024
BartleCALIFORNIA32021
TionestaCALIFORNIA32021
MadelineCALIFORNIA31998
Clear Lk ResCALIFORNIA21995
HackamoreCALIFORNIA22009

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