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

White-eyed Vireo Population Trend in Illinois

All statesForest birds

White-eyed Vireo in Illinois has surged: up 554% on the route-weighted index since 1968.

+554%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 →
65Routes 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 White-eyed Vireo Trends in IllinoisNotable 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 →

White-eyed Vireo has surged in Illinois: up 554% on the route-weighted index since 1968.

White-eyed Vireo Population Forecast in Illinois

If the recent trend holds, White-eyed Vireo in Illinois is projected to stay roughly flat through 2029, near 2.1 (95% range 1.3–2.9). A 5-year backtest shows a typical error of ±28.7%, with 60% of held-out values landing inside the 95% band.

+4%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 →
2.1Projected 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 →
1.3–2.995% 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 →
±28.7%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, White-eyed Vireo in Illinois is projected to stay roughly flat through 2029, near 2.1 (95% range 1.3–2.9). A 5-year backtest shows a typical error of ±28.7%, with 60% 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 →
20252.01.22.8
20262.01.22.9
20272.11.32.9
20282.11.32.9
20292.11.32.9

White-eyed Vireo Survey Routes in Illinois

Routes recording White-eyed Vireo in Illinois.
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 →
Sandusky6720231993
Cave In Rock3320241993
Delwood3120241970
Beaverdam Lk2320231970
Belknap1920241970
Bremen1820241969
Pulaski1720241970
Royalton1520242002
Karnak920232001
Belleview520241967
York520242000
Mascoutah Lk420231971
Brownville320231994
Athensville220041974
Concord220231969
Pawnee220031967
Le Roy219981998
Eldred220211993
Cherry Val119911972
Athens120131995
Payson120012001
Clayton120232018
Sheffield120191986
Wayne120052005
Sherburnvill120192009

White-eyed Vireo Population Trend in Other States

alabamaarkansasconnecticutdelawarefloridageorgiaindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganmississippimissourinebraskanew-jerseynew-yorknorth-carolinaohiooklahomapennsylvaniarhode-islandsouth-carolinatennesseetexasvirginiawest-virginiawisconsin

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