BirdAnalyst
Species · Rhode Island · BBS 2025 Release · 1966–2024

Purple Finch Population Trend in Rhode Island

All statesGeneralists

Purple Finch in Rhode Island has collapsed: down 81% on the route-weighted index since 1968.

-81%Since 1968TrendPercent 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 →
6Routes 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 →
23YearsYears 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 Rhode IslandNotable 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 Rhode Island: down 81% on the route-weighted index since 1968.

Purple Finch Population Forecast in Rhode Island

If the recent trend holds, Purple Finch in Rhode Island is projected to fall about 100% by 2021 — from 0.25 in 2016 to a central estimate of 0.00 (95% range 0.00–2.0). A 5-year backtest shows a typical error of ±214%, with 100% of held-out values landing inside the 95% band.

-100%Change by 2021TrendPercent 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 2021 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–2.095% 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 →
±214%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 Rhode Island is projected to fall about 100% by 2021 — from 0.25 in 2016 to a central estimate of 0.00 (95% range 0.00–2.0). A 5-year backtest shows a typical error of ±214%, with 100% of held-out values landing inside the 95% band.19662021
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 →
20170.000.002.0
20180.000.002.0
20190.000.002.0
20200.000.002.0
20210.000.002.0

Purple Finch Survey Routes in Rhode Island

Routes recording Purple Finch in Rhode Island.
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 →
Quonset Pt219921966
Sachuest Pt219881966
Shannock119901973
Wallum Lake119891973
Pulaski119911991
Casimir Pulaski Sf120162016

Purple Finch Population Trend in Other States

alaskacaliforniaconnecticutindianamainemarylandmassachusettsmichiganminnesotanew-hampshirenew-jerseynew-yorknorth-dakotaohiooregonpennsylvaniavermontwashingtonwest-virginiawisconsin

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