BirdAnalyst
Species · Vermont · BBS 2025 Release · 1966–2024

Northern Waterthrush Population Trend in Vermont

All statesForest birds

Northern Waterthrush in Vermont has increased: up 45% on the route-weighted index since 1969.

+45%Since 1969TrendPercent 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 →
23Routes 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 →
57YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Northern 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 →

No notable trend signals for Northern Waterthrush in Vermont. See the full index history below.

Northern Waterthrush Population Forecast in Vermont

If the recent trend holds, Northern Waterthrush in Vermont is projected to fall about 11% by 2029 — from 0.28 in 2024 to a central estimate of 0.25 (95% range 0.00–0.59). A 5-year backtest shows a typical error of ±180.5%, with 100% of held-out values landing inside the 95% band.

-11%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 →
0.25Projected 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 →
0.00–0.5995% 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 →
±180.5%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, Northern Waterthrush in Vermont is projected to fall about 11% by 2029 — from 0.28 in 2024 to a central estimate of 0.25 (95% range 0.00–0.59). A 5-year backtest shows a typical error of ±180.5%, with 100% 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 →
20250.250.000.59
20260.250.000.59
20270.250.000.59
20280.250.000.59
20290.250.000.59

Northern Waterthrush Survey Routes in Vermont

Routes recording Northern 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 →
Hardwick220241968
Greensboro220081971
Marlboro119911970
North Pownal119761976
Stratton120241970
Landgrove120211984
S Reading120191976
Gaysville120042004
Post Mills120231975
Shaftsbury119791979
S Wallingfrd119881972
W Rutland120241979
St Johnsbury120042001
East Haven120241966
Northfld Fls120161980
Middlesex120131975
East Calais120151971
Newbury119901990
Hinesburg119921977
Colchester120191987
Newbury 2120162015
Stowe120101988
Bristol119961996

Northern Waterthrush Population Trend in Other States

alaskaconnecticutidahomainemarylandmassachusettsmichiganminnesotamontananew-hampshirenew-jerseynew-yorknorth-carolinanorth-dakotaohiopennsylvaniarhode-islandvirginiawashingtonwest-virginiawisconsinwyoming

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