BirdAnalyst
Species · Vermont · BBS 2026 Release · 1966–2025

Louisiana Waterthrush Population Trend in Vermont

All statesForest birds

Louisiana Waterthrush in Vermont has surged: up 390% on the route-weighted index since 1973.

+390%Since 1973TrendPercent 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 →
13Routes 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 →
48YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Louisiana Waterthrush Trends in VermontNotable 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 →

Louisiana Waterthrush has surged in Vermont: up 390% on the route-weighted index since 1973.

Louisiana Waterthrush Population Forecast in Vermont

If the recent trend holds, Louisiana Waterthrush in Vermont is projected to fall about 44% by 2030 — from 0.39 in 2025 to a central estimate of 0.22 (95% range 0.03–0.41). A 5-year backtest shows a typical error of ±37.6%, with 80% of held-out values landing inside the 95% band.

-44%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 →
0.22Projected 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 →
0.03–0.4195% 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 →
±37.6%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, Louisiana Waterthrush in Vermont is projected to fall about 44% by 2030 — from 0.39 in 2025 to a central estimate of 0.22 (95% range 0.03–0.41). A 5-year backtest shows a typical error of ±37.6%, with 80% of held-out values landing inside the 95% band.19712030
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 →
20260.210.030.40
20270.210.030.40
20280.220.030.40
20290.220.030.40
20300.220.030.41

Louisiana Waterthrush Survey Routes in Vermont

Routes recording Louisiana Waterthrush in Vermont.
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 →
Marlboro320251975
Shaftsbury220251973
North Pownal119931991
Stratton120251972
S Reading120191971
Gaysville120251978
Post Mills120211982
S Wallingfrd120091974
W Rutland120191976
Middlesex119921975
Hardwick120112011
Hinesburg119771977
Bristol120182016

Louisiana Waterthrush Population Trend in Other States

alabamaarkansasconnecticutdelawarefloridageorgiaillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourinew-hampshirenew-jerseynew-yorknorth-carolinaohiooklahomapennsylvaniarhode-islandsouth-carolinatennesseetexasvirginiawest-virginiawisconsin

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