BirdAnalyst
Species · BCR 11 · BBS 2025 Release · 1966–2024

Purple Finch In Prairie Potholes

All regionsPrairie PotholesGeneralists

Purple Finch in Prairie Potholes has fallen sharply: down 64% on the route-weighted index since 1976.

-64%Since 1976TrendPercent 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 →
10Routes 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 →
26YearsYears 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 Prairie Potholes. See the full index history below.

Purple Finch In Prairie Potholes Population Forecast

If the recent trend holds, Purple Finch in Prairie Potholes is projected to stay roughly flat through 2028, near 0.02 (95% range 0.00–0.07). A 5-year backtest shows a typical error of ±126.2%, with 100% of held-out values landing inside the 95% band.

n/aChange by 2028TrendPercent 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 →
0.02Projected 2028 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–0.0795% 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 →
±126.2%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 Prairie Potholes is projected to stay roughly flat through 2028, near 0.02 (95% range 0.00–0.07). A 5-year backtest shows a typical error of ±126.2%, with 100% of held-out values landing inside the 95% band.19692028
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 →
20240.020.000.07
20250.020.000.07
20260.020.000.07
20270.020.000.07
20280.020.000.07

Routes In Prairie Potholes

Routes recording Purple Finch in Prairie Potholes.
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 →
BeltramiMINNESOTA51998
ArlingtonMINNESOTA11978
MaynardMINNESOTA11999
OkleeMINNESOTA11990
WylieMINNESOTA11976
ErieMINNESOTA11977
BadgerMINNESOTA12017
Lake BronsonMINNESOTA11998
RollaNORTH-DAKOTA12004
Turtle MtnsNORTH-DAKOTA12023

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