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

Black-and-white Warbler Population Trend in Vermont

All statesForest birds

Black-and-white Warbler in Vermont has surged: up 168% on the route-weighted index since 1968.

+168%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 →
26Routes 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 →
58YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Black-and-white 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 →

long arc increasecomputed 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 →

Black-and-white Warbler has surged in Vermont: up 168% on the route-weighted index since 1968.

Black-and-white Warbler Population Forecast in Vermont

If the recent trend holds, Black-and-white Warbler in Vermont is projected to rise about 16% by 2029 — from 3.2 in 2024 to a central estimate of 3.7 (95% range 1.7–5.6). A 5-year backtest shows a typical error of ±34.9%, with 100% of held-out values landing inside the 95% band.

+16%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 →
3.7Projected 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 →
1.7–5.695% 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 →
±34.9%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, Black-and-white Warbler in Vermont is projected to rise about 16% by 2029 — from 3.2 in 2024 to a central estimate of 3.7 (95% range 1.7–5.6). A 5-year backtest shows a typical error of ±34.9%, with 100% of held-out values landing inside the 95% band.19662029
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 →
20253.61.65.5
20263.61.65.6
20273.61.65.6
20283.61.75.6
20293.71.75.6

Black-and-white Warbler Survey Routes in Vermont

Routes recording Black-and-white 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 →
Marlboro1120241966
Gaysville920211966
Newbury 2820232005
Post Mills620241966
East Haven620241967
Hardwick620241967
Stowe620241988
Shaftsbury520241968
Hinesburg519941977
Northfld Fls420211980
Landgrove320241966
S Wallingfrd320221969
W Rutland320241972
East Calais320241966
Fletcher320241968
St Johnsbury220241970
Newbury220021987
Waterville219801979
Bristol220181995
North Pownal120211966
Stratton120241966
S Reading120241966
Middlesex120241968
Greensboro120221967
Colchester120091986

Black-and-white Warbler Population Trend in Other States

alabamaarkansascaliforniaconnecticutdelawaregeorgiaillinoisindianakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourinebraskanew-hampshirenew-jerseynew-yorknorth-carolinanorth-dakotaohiooklahomapennsylvaniarhode-islandsouth-carolinatennesseetexasvirginiawest-virginiawisconsinwyoming

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