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Species · Connecticut · BBS 2025 Release · 1966–2024

Yellow-throated Vireo Population Trend in Connecticut

All statesForest birds

Yellow-throated Vireo in Connecticut has risen sharply: up 56% on the route-weighted index since 1968.

+56%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 →
20Routes 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 Yellow-throated Vireo Trends in ConnecticutNotable 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 risen sharply in Connecticut: up 56% on the route-weighted index since 1968.

Yellow-throated Vireo Population Forecast in Connecticut

If the recent trend holds, Yellow-throated Vireo in Connecticut is projected to stay roughly flat through 2029, near 1.9 (95% range 0.76–3.1). A 5-year backtest shows a typical error of ±16.5%, with 100% of held-out values landing inside the 95% band.

-8%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 →
1.9Projected 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 →
0.76–3.195% 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 →
±16.5%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, Yellow-throated Vireo in Connecticut is projected to stay roughly flat through 2029, near 1.9 (95% range 0.76–3.1). A 5-year backtest shows a typical error of ±16.5%, 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 →
20251.90.743.1
20261.90.743.1
20271.90.753.1
20281.90.753.1
20291.90.763.1

Yellow-throated Vireo Survey Routes in Connecticut

Routes recording Yellow-throated Vireo in Connecticut.
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 →
Willimantic720181967
Warren 2720232012
Woodstock 2620242016
Uncasville420241973
Warren420111973
Long Hill420191972
E Hartland319921968
No Woodbury320241967
Granby320241988
Buckingham220221966
Sherman220191974
Mid Haddam220241974
New Hartford219871974
Mystic120231974
Woodstock120071968
Westbrook120191977
Greenwich120101969
Danbury120131968
Southington120221973
New Hartford120241994

Yellow-throated Vireo Population Trend in Other States

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

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