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Species · BCR 14 · BBS 2026 Release · 1966–2025

Black-throated Green Warbler In Atlantic Northern Forest

All regionsAtlantic Northern ForestForest birds

Black-throated Green Warbler in Atlantic Northern Forest has surged: up 141% on the route-weighted index since 1968.

+141%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 →
155Routes 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 →
59YearsYears 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 →

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-throated Green Warbler has surged in Atlantic Northern Forest: up 141% on the route-weighted index since 1968.

Black-throated Green Warbler In Atlantic Northern Forest Population Forecast

If the recent trend holds, Black-throated Green Warbler in Atlantic Northern Forest is projected to rise about 62% by 2030 — from 4.0 in 2025 to a central estimate of 6.5 (95% range 4.2–8.8). A 5-year backtest shows a typical error of ±77.1%, with 0% of held-out values landing inside the 95% band.

+62%Change by 2030TrendPercent 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 →
6.5Projected 2030 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
4.2–8.895% 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 →
±77.1%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-throated Green Warbler in Atlantic Northern Forest is projected to rise about 62% by 2030 — from 4.0 in 2025 to a central estimate of 6.5 (95% range 4.2–8.8). A 5-year backtest shows a typical error of ±77.1%, with 0% of held-out values landing inside the 95% band.19662030
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 →
20266.24.08.5
20276.34.08.6
20286.44.18.6
20296.44.18.7
20306.54.28.8

Routes In Atlantic Northern Forest

Routes recording Black-throated Green Warbler in Atlantic Northern Forest.
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 →
NorthfieldMAINE851981
InletNEW-YORK322017
CooperMAINE302021
WaiteMAINE271977
Old ForgeNEW-YORK232006
SabattisNEW-YORK211983
Seboomook LkMAINE202014
Blue Ridge SNEW-YORK172010
NesowadnehunMAINE152021
Dixvil NotchNEW-HAMPSHIRE152017
Dixville Notch 2NEW-HAMPSHIRE152025
Dexter LakeNEW-YORK151975
Old Forge 2NEW-YORK152019
EastbrookMAINE142025
Grnd Lk StrmMAINE132000
AndoverMAINE132021
StoweVERMONT132024
BrooksMAINE112021
TopsfieldMAINE111996
GaysvilleVERMONT112025
Wilson MillsMAINE102025
CummingtonMASSACHUSETTS102014
WalpoleNEW-HAMPSHIRE102025
StrattonVERMONT102025
WinnMAINE92025

Source: USGS North American Breeding Bird Survey, retrieved 2026-08-14.