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Species · Massachusetts · BBS 2025 Release · 1966–2024

Yellow-throated Vireo Population Trend in Massachusetts

All statesForest birds

Yellow-throated Vireo in Massachusetts has surged: up 810% on the route-weighted index since 1974.

+810%Since 1974TrendPercent 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 →
21Routes 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 →
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 Yellow-throated Vireo Trends in MassachusettsNotable 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 →

Yellow-throated Vireo has surged in Massachusetts: up 810% on the route-weighted index since 1974.

Yellow-throated Vireo Population Forecast in Massachusetts

If the recent trend holds, Yellow-throated Vireo in Massachusetts is projected to fall about 39% by 2029 — from 1.1 in 2024 to a central estimate of 0.69 (95% range 0.19–1.2). A 5-year backtest shows a typical error of ±61.4%, with 0% of held-out values landing inside the 95% band.

-39%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 →
0.69Projected 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 →
0.19–1.295% 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 →
±61.4%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, Yellow-throated Vireo in Massachusetts is projected to fall about 39% by 2029 — from 1.1 in 2024 to a central estimate of 0.69 (95% range 0.19–1.2). A 5-year backtest shows a typical error of ±61.4%, with 0% of held-out values landing inside the 95% band.19712029
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 →
20250.650.151.2
20260.660.161.2
20270.670.171.2
20280.680.181.2
20290.690.191.2

Yellow-throated Vireo Survey Routes in Massachusetts

Routes recording Yellow-throated Vireo in Massachusetts.
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 →
Belchertown520241978
S Barre420241977
Warren320081974
Sheffield320221971
Monterey320242019
Holden320241987
Warren 2320232011
Maynard220221997
N Oxford220041995
Cummington219861975
Hancock220152009
Ware River120211995
Prattville120141997
Littleton120181978
E Pepperell119771977
N Orange120181972
Chesterfield120241971
Cheshire119921972
Pittsfield120061972
N. Andover120241995
Cummington 2120192019

Yellow-throated Vireo Population Trend in Other States

alabamaarkansasconnecticutdelawarefloridageorgiaillinoisindianaiowakansaskentuckylouisianamainemarylandmichiganminnesotamississippimissourinebraskanew-hampshirenew-jerseynew-yorknorth-carolinanorth-dakotaohiooklahomapennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasvermontvirginiawest-virginiawisconsin

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