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Species · BCR 14 · BBS 2025 Release · 1966–2024

Black-and-white Warbler In Atlantic Northern Forest

All regionsAtlantic Northern ForestForest birds

Black-and-white Warbler in Atlantic Northern Forest has risen sharply: up 72% on the route-weighted index since 1968.

+72%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 →
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 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 risen sharply in Atlantic Northern Forest: up 72% 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 stay roughly flat through 2029, near 4.5 (95% range 2.4–6.6). A 5-year backtest shows a typical error of ±2.8%, with 100% of held-out values landing inside the 95% band.

-1%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 →
4.5Projected 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 →
2.4–6.695% 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 →
±2.8%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 stay roughly flat through 2029, near 4.5 (95% range 2.4–6.6). A 5-year backtest shows a typical error of ±2.8%, 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 →
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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
ChesterfieldMASSACHUSETTS282024
InletNEW-YORK182017
CooperMAINE172021
East TroyMAINE162019
BrooksMAINE162019
CharlestonMAINE162019
MedwayMAINE162018
HudsonMAINE162016
LempsterNEW-HAMPSHIRE162024
HarmonyMAINE152024
HermonMAINE152019
Seboomook LkMAINE132014
N OrangeMASSACHUSETTS132024
TopsfieldMAINE121996
AuroraMAINE112021
WaiteMAINE111977
SearsportMAINE112024
WanakenaNEW-YORK112024
MarlboroVERMONT112024
Forest StaMAINE102000
StacyvilleMAINE92024
PittsfieldMASSACHUSETTS92016
FitzwilliamNEW-HAMPSHIRE92024
GaysvilleVERMONT92021

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