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

Blackpoll Warbler Population Trend in Vermont

All statesForest birds

Blackpoll Warbler in Vermont has held roughly steady: down 10% on the route-weighted index since 1972.

-10%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 →
11Routes 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 →
18YearsYears 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 VermontNotable 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 Blackpoll Warbler in Vermont. See the full index history below.

Blackpoll Warbler Population Forecast in Vermont

If the recent trend holds, Blackpoll Warbler in Vermont is projected to stay roughly flat through 2028, near 0.05 (95% range 0.00–0.16). A 5-year backtest shows a typical error of ±48.4%, with 100% of held-out values landing inside the 95% band.

-7%Change 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 →
0.05Projected 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 →
0.00–0.1695% 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 →
±48.4%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 Vermont is projected to stay roughly flat through 2028, near 0.05 (95% range 0.00–0.16). A 5-year backtest shows a typical error of ±48.4%, with 100% of held-out values landing inside the 95% band.19682028
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 →
20240.060.000.16
20250.060.000.16
20260.050.000.16
20270.050.000.16
20280.050.000.16

Blackpoll Warbler Survey Routes in Vermont

Routes recording Blackpoll Warbler in Vermont.
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 →
Middlesex220082008
Stratton120211972
Landgrove119901989
Post Mills120182016
St Johnsbury119741974
East Haven119741974
Northfld Fls119961996
East Calais120231968
Greensboro120041970
Fletcher120222022
Stowe120071996

Blackpoll Warbler Population Trend in Other States

alaskamainemassachusettsnew-hampshirenew-yorkpennsylvania

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