BirdAnalyst
Species · Maine · BBS 2025 Release · 1966–2024

Blackpoll Warbler Population Trend in Maine

All statesForest birds

Blackpoll Warbler in Maine has collapsed: down 83% on the route-weighted index since 1972.

-83%Since 1972TrendPercent 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 →
32Routes 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 →
37YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Blackpoll Warbler Trends in MaineNotable 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 →

Blackpoll Warbler has collapsed in Maine: down 83% on the route-weighted index since 1972.

Blackpoll Warbler Population Forecast in Maine

If the recent trend holds, Blackpoll Warbler in Maine is projected to fall about 100% by 2029 — from 0.05 in 2024 to a central estimate of 0.00 (95% range 0.00–0.24). A 5-year backtest shows a typical error of ±239.3%, with 100% of held-out values landing inside the 95% band.

-100%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 →
0.00Projected 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 →
0.00–0.2495% 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 →
±239.3%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, Blackpoll Warbler in Maine is projected to fall about 100% by 2029 — from 0.05 in 2024 to a central estimate of 0.00 (95% range 0.00–0.24). A 5-year backtest shows a typical error of ±239.3%, 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 →
20250.000.000.24
20260.000.000.24
20270.000.000.24
20280.000.000.24
20290.000.000.24

Blackpoll Warbler Survey Routes in Maine

Routes recording Blackpoll Warbler in Maine.
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 →
Clayton Lake419921977
Greenwood219721972
Benton219721971
Baxter219881988
Cambridge219761976
Medway220181976
Yankeetuladi219941994
Biddeford119891980
Wilson Mills120061994
Bethel120191972
Turner119741972
Reeds120242024
Nesowadnehun120192019
Otisfield Gr119861971
Hartford119761976
Manchester119821971
Warren119751975
Freedom119761976
Harmony119871987
Heron Lake119941994
Cooper119921992
Moose River119931993
Carrying Pl120211994
Greenville119771977
Winn119971997

Blackpoll Warbler Population Trend in Other States

alaskamassachusettsnew-hampshirenew-yorkpennsylvaniavermont

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