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

Black-and-white Warbler In Atlantic Northern Forest

All regionsAtlantic Northern ForestForest birds

Black-and-white Warbler in Atlantic Northern Forest has surged: up 87% on the route-weighted index since 1968.

+87%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-and-white Warbler has surged in Atlantic Northern Forest: up 87% on the route-weighted index since 1968.

Black-and-white Warbler In Atlantic Northern Forest Population Forecast

If the recent trend holds, Black-and-white Warbler in Atlantic Northern Forest is projected to fall about 19% by 2030 — from 5.7 in 2025 to a central estimate of 4.6 (95% range 2.5–6.7). A 5-year backtest shows a typical error of ±8.6%, with 100% of held-out values landing inside the 95% band.

-19%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 →
4.6Projected 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 →
2.5–6.795% 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 →
±8.6%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 Atlantic Northern Forest is projected to fall about 19% by 2030 — from 5.7 in 2025 to a central estimate of 4.6 (95% range 2.5–6.7). A 5-year backtest shows a typical error of ±8.6%, with 100% 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 →
20264.62.56.7
20274.62.56.7
20284.62.56.7
20294.62.56.7
20304.62.56.7

Routes In Atlantic Northern Forest

Routes recording Black-and-white 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 →
NorthfieldMAINE481981
HermonMAINE252021
GaysvilleVERMONT212025
East TroyMAINE202021
WytopitlockMAINE182025
ChesterfieldMASSACHUSETTS182025
InletNEW-YORK182017
BrooksMAINE172021
CooperMAINE172021
WinnMAINE172025
HudsonMAINE162016
N OrangeMASSACHUSETTS152025
HarmonyMAINE142025
Seboomook LkMAINE132014
MarlowNEW-HAMPSHIRE132025
WanakenaNEW-YORK132025
TopsfieldMAINE121996
AuroraMAINE112021
WaiteMAINE111977
EastbrookMAINE102025
MedwayMAINE102025
Forest StaMAINE102000
MontereyMASSACHUSETTS102025
North RiverNEW-YORK102025
DegrasseNEW-YORK102025

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