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Species · Connecticut · BBS 2026 Release · 1966–2025

Red-eyed Vireo Population Trend in Connecticut

All statesForest birds

Red-eyed Vireo in Connecticut has surged: up 101% on the route-weighted index since 1968.

+101%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 →
59YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Red-eyed 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 →

Red-eyed Vireo has surged in Connecticut: up 101% on the route-weighted index since 1968.

Red-eyed Vireo Population Forecast in Connecticut

If the recent trend holds, Red-eyed Vireo in Connecticut is projected to rise about 15% by 2030 — from 28 in 2025 to a central estimate of 32 (95% range 22–41). A 5-year backtest shows a typical error of ±17.3%, with 100% of held-out values landing inside the 95% band.

+15%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 →
32Projected 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 →
22–4195% 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 →
±17.3%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, Red-eyed Vireo in Connecticut is projected to rise about 15% by 2030 — from 28 in 2025 to a central estimate of 32 (95% range 22–41). A 5-year backtest shows a typical error of ±17.3%, with 100% of held-out values landing inside the 95% band.19662030
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 →
2026302139
2027312140
2028312240
2029312240
2030322241

Red-eyed Vireo Survey Routes in Connecticut

Routes recording Red-eyed 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 →
Warren12820111972
Woodstock 27620252016
Warren 24320252012
Woodstock4020071968
Granby3520251988
New Hartford3120241994
Willimantic2720181967
New Hartford2619871972
Mid Haddam2120251973
Uncasville2020251973
Sherman1920191972
E Hartland1819921966
Long Hill1520191972
No Woodbury1120251967
Danbury1120231968
Southington1020251973
Mystic920231973
Buckingham620221966
Greenwich620181967
Westbrook420251969

Red-eyed Vireo Population Trend in Other States

alabamaalaskaarkansascoloradodelawarefloridageorgiaidahoillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasvermontvirginiawashingtonwest-virginiawisconsinwyoming

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