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

White-eyed Vireo Population Trend in Delaware

All statesForest birds

White-eyed Vireo in Delaware has increased: up 31% on the route-weighted index since 1968.

+31%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 →
17Routes 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 DelawareNotable signalsLong-arc shifts the engine flags automatically — sustained declines or increases large enough to stand out from year-to-year noise.Full methodology →

No notable trend signals for White-eyed Vireo in Delaware. See the full index history below.

White-eyed Vireo Population Forecast in Delaware

If the recent trend holds, White-eyed Vireo in Delaware is projected to fall about 41% by 2029 — from 5.2 in 2024 to a central estimate of 3.1 (95% range 0.54–5.6). A 5-year backtest shows a typical error of ±38.8%, with 80% of held-out values landing inside the 95% band.

-41%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 →
3.1Projected 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 →
0.54–5.695% 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 →
±38.8%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 Delaware is projected to fall about 41% by 2029 — from 5.2 in 2024 to a central estimate of 3.1 (95% range 0.54–5.6). A 5-year backtest shows a typical error of ±38.8%, with 80% 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 →
20253.20.665.7
20263.20.635.7
20273.10.605.7
20283.10.575.7
20293.10.545.6

White-eyed Vireo Survey Routes in Delaware

Routes recording White-eyed Vireo in Delaware.
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 →
Millsboro1020242017
Pepperbox 21020242017
Pepperbox620161998
Frederica420141966
Holleyville420041966
Milton420151966
Dover319871968
Frankford320121966
Lowes Xrds319911966
Blackbird320241994
Georgetown320221992
Milton 2320172017
Mt Pleasant220181966
Wilmington220101969
Holleyville 2220242006
Harrington120241966
Bethany Bch119901966

White-eyed Vireo Population Trend in Other States

alabamaarkansasconnecticutfloridageorgiaillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganmississippimissourinebraskanew-jerseynew-yorknorth-carolinaohiooklahomapennsylvaniarhode-islandsouth-carolinatennesseetexasvirginiawest-virginiawisconsin

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