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Species · Tennessee · BBS 2026 Release · 1966–2025

Worm-eating Warbler Population Trend in Tennessee

All statesForest birds

Worm-eating Warbler in Tennessee has surged: up 115% on the route-weighted index since 1968.

+115%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 →
40Routes In StateSurvey 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 Worm-eating Warbler Trends in TennesseeNotable 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 →

Worm-eating Warbler has surged in Tennessee: up 115% on the route-weighted index since 1968.

Worm-eating Warbler Population Forecast in Tennessee

If the recent trend holds, Worm-eating Warbler in Tennessee is projected to rise about 149% by 2030 — from 0.45 in 2025 to a central estimate of 1.1 (95% range 0.50–1.7). A 5-year backtest shows a typical error of ±74.2%, with 60% of held-out values landing inside the 95% band.

+149%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 →
1.1Projected 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 →
0.50–1.795% 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 →
±74.2%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 Tennessee is projected to rise about 149% by 2030 — from 0.45 in 2025 to a central estimate of 1.1 (95% range 0.50–1.7). A 5-year backtest shows a typical error of ±74.2%, with 60% 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 →
20261.10.451.7
20271.10.461.7
20281.10.471.7
20291.10.491.7
20301.10.501.7

Worm-eating Warbler Survey Routes in Tennessee

Routes recording Worm-eating Warbler in Tennessee.
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 →
Mecca820231994
Mcfarland819931967
Harbuck720231994
Willis Sprng420221994
Tellico420251995
Tullahoma420151968
Lewis Forest320241966
Cornpone320241990
Newfound Gap320181990
Pond Creek220251972
Indian Mound219871987
Wrigley220221968
Bradyville220041972
Trace Collinwood220182015
Trace Lewis220172013
Signal Mtn120231979
Tiptonville120151969
Jones Gap119861985
Big Sandy120252016
Mansfield120251998
Sweetlips120151988
Silerton120242022
Trenton120082008
Collinwood120251966
Campbellsville120171988

Worm-eating Warbler Population Trend in Other States

alabamaarkansasconnecticutdelawaregeorgiaillinoisindianaiowakentuckylouisianamarylandmassachusettsmississippimissourinew-hampshirenew-jerseynew-yorknorth-carolinaohiooklahomapennsylvaniarhode-islandsouth-carolinatexasvirginiawest-virginiawisconsin

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