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

Chestnut-sided Warbler In Atlantic Northern Forest

All regionsAtlantic Northern ForestForest birds

Chestnut-sided Warbler in Atlantic Northern Forest has edged up: up 15% on the route-weighted index since 1968.

+15%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 →

No notable trend signals for Chestnut-sided Warbler in Atlantic Northern Forest. See the full index history below.

Forecast

If the recent trend holds, Chestnut-sided Warbler in Atlantic Northern Forest is projected to fall about 40% by 2029 — from 13 in 2024 to a central estimate of 7.6 (95% range 3.8–12). A 5-year backtest shows a typical error of ±38.1%, with 20% of held-out values landing inside the 95% band.

-40%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 →
7.6Projected 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 →
3.8–1295% 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 →
±38.1%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, Chestnut-sided Warbler in Atlantic Northern Forest is projected to fall about 40% by 2029 — from 13 in 2024 to a central estimate of 7.6 (95% range 3.8–12). A 5-year backtest shows a typical error of ±38.1%, with 20% 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 →
20258.04.112
20267.94.012
20277.84.012
20287.73.912
20297.63.812

Routes In Atlantic Northern Forest

Routes recording Chestnut-sided 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 →
DegrasseNEW-YORK442024
StoweVERMONT382024
WanakenaNEW-YORK362024
LempsterNEW-HAMPSHIRE252024
GlenNEW-HAMPSHIRE242024
HighmarketNEW-YORK232024
East TroyMAINE222019
East CalaisVERMONT222024
Jefferson HlNEW-HAMPSHIRE212024
StratfordNEW-HAMPSHIRE212024
CornvilleMAINE202024
Dexter LakeNEW-YORK201975
ChesterfieldMASSACHUSETTS192024
PittsfieldMASSACHUSETTS192016
Cummington 2MASSACHUSETTS192024
S WallingfrdVERMONT192022
HardwickVERMONT192024
WatervilleVERMONT191980
KasoagNEW-YORK182024
FletcherVERMONT182024
BrooksMAINE172019
CastineMAINE172006
N OrangeMASSACHUSETTS172024
St Regis FlsNEW-YORK172017
StrattonVERMONT172024

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