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

Tennessee Warbler In Atlantic Northern Forest

All regionsAtlantic Northern ForestForest birds

Tennessee Warbler in Atlantic Northern Forest has fallen sharply: down 63% on the route-weighted index since 1968.

-63%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 →
84Routes 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 →
52YearsYears 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 declinecomputed 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 →

Tennessee Warbler has fallen sharply in Atlantic Northern Forest: down 63% on the route-weighted index since 1968.

Tennessee Warbler In Atlantic Northern Forest Population Forecast

If the recent trend holds, Tennessee Warbler in Atlantic Northern Forest is projected to stay roughly flat through 2027, near 0.01 (95% range 0.00–0.41). A 5-year backtest shows a typical error of ±135.8%, with 100% of held-out values landing inside the 95% band.

n/aChange by 2027TrendPercent 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 →
0.01Projected 2027 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–0.4195% 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 →
±135.8%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, Tennessee Warbler in Atlantic Northern Forest is projected to stay roughly flat through 2027, near 0.01 (95% range 0.00–0.41). A 5-year backtest shows a typical error of ±135.8%, with 100% of held-out values landing inside the 95% band.19662027
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 →
20230.030.000.43
20240.030.000.43
20250.020.000.42
20260.020.000.41
20270.010.000.41

Routes In Atlantic Northern Forest

Routes recording Tennessee 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 →
NorthfieldMAINE181981
WinnMAINE91997
BaxterMAINE71984
Seboomook LkMAINE71993
WaiteMAINE61977
Clayton Lake 2MAINE42011
Clayton LakeMAINE32008
WashburnMAINE31993
TopsfieldMAINE31992
St JohnsburyVERMONT32005
Otisfield GrMAINE21976
ManchesterMAINE21974
BentonMAINE21977
Carrying PlMAINE21993
CambridgeMAINE21983
BoundaryMAINE22004
Ft FairfieldMAINE21998
St DavidMAINE21992
Weeks BrookMAINE22015
Baker LakeMAINE22004
Heron LakeMAINE21999
MilanNEW-HAMPSHIRE22019
GlenNEW-HAMPSHIRE21994
GabrielsNEW-YORK21999
Horseshoe L.NEW-YORK22017

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