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

Worm-eating Warbler In Atlantic Northern Forest

All regionsAtlantic Northern ForestForest birds

Worm-eating Warbler in Atlantic Northern Forest has held roughly steady: up 1% on the route-weighted index since 1981.

+1%Since 1981TrendPercent 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 →
9Routes 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 →
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 SignalsNotable 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 Worm-eating Warbler in Atlantic Northern Forest. See the full index history below.

Worm-eating Warbler In Atlantic Northern Forest Population Forecast

If the recent trend holds, Worm-eating Warbler in Atlantic Northern Forest is projected to stay roughly flat through 2029, near 0.02 (95% range 0.00–0.04). A 5-year backtest shows a typical error of ±40.3%, with 100% of held-out values landing inside the 95% band.

n/aChange 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 →
0.02Projected 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 →
0.00–0.0495% 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 →
±40.3%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, Worm-eating Warbler in Atlantic Northern Forest is projected to stay roughly flat through 2029, near 0.02 (95% range 0.00–0.04). A 5-year backtest shows a typical error of ±40.3%, with 100% of held-out values landing inside the 95% band.19722029
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 →
20250.020.000.04
20260.020.000.04
20270.020.000.04
20280.020.000.04
20290.020.000.04

Routes In Atlantic Northern Forest

Routes recording Worm-eating 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 →
SheffieldMASSACHUSETTS22022
New HartfordCONNECTICUT11984
New HartfordCONNECTICUT12005
N OrangeMASSACHUSETTS11983
MontereyMASSACHUSETTS12024
LempsterNEW-HAMPSHIRE12003
PetersburgNEW-YORK11972
HighmarketNEW-YORK12002
DannemoraNEW-YORK11997

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