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

Magnolia Warbler Population Trend in Vermont

All statesForest birds

Magnolia Warbler in Vermont has surged: up 150% on the route-weighted index since 1968.

+150%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 →
24Routes 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 →
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 Magnolia Warbler 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 →

Magnolia Warbler has surged in Vermont: up 150% on the route-weighted index since 1968.

Magnolia Warbler Population Forecast in Vermont

If the recent trend holds, Magnolia Warbler in Vermont is projected to rise about 29% by 2029 — from 1.2 in 2024 to a central estimate of 1.6 (95% range 0.22–2.9). A 5-year backtest shows a typical error of ±66.9%, with 100% of held-out values landing inside the 95% band.

+29%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 →
1.6Projected 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 →
0.22–2.995% 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 →
±66.9%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, Magnolia Warbler in Vermont is projected to rise about 29% by 2029 — from 1.2 in 2024 to a central estimate of 1.6 (95% range 0.22–2.9). A 5-year backtest shows a typical error of ±66.9%, 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 →
20251.60.222.9
20261.60.222.9
20271.60.222.9
20281.60.222.9
20291.60.222.9

Magnolia Warbler Survey Routes in Vermont

Routes recording Magnolia Warbler 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 →
Fletcher820131983
East Haven620241968
Newbury 2520232005
Stratton420241967
Hardwick420241973
Post Mills319941967
East Calais320241967
Middlesex220241968
Greensboro220231967
Stowe220221988
Marlboro120241986
North Pownal119671967
Landgrove120241966
S Reading120091968
Gaysville120001978
Shaftsbury120151977
S Wallingfrd120001976
W Rutland120171992
St Johnsbury120241970
Northfld Fls120211980
Newbury120041987
Waterville119801980
Hinesburg119781970
Grand Isle119931993

Magnolia Warbler Population Trend in Other States

connecticutmainemarylandmassachusettsmichiganminnesotanew-hampshirenew-jerseynew-yorknorth-carolinaohiopennsylvaniavirginiawest-virginiawisconsin

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