BirdAnalyst
Species · Iowa · BBS 2026 Release · 1966–2025

Red-eyed Vireo Population Trend in Iowa

All statesForest birds

Red-eyed Vireo in Iowa has increased: up 32% on the route-weighted index since 1969.

+32%Since 1969TrendPercent 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 →
37Routes 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 →
57YearsYears 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 IowaNotable 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 Red-eyed Vireo in Iowa. See the full index history below.

Red-eyed Vireo Population Forecast in Iowa

If the recent trend holds, Red-eyed Vireo in Iowa is projected to stay roughly flat through 2030, near 0.41 (95% range 0.14–0.69). A 5-year backtest shows a typical error of ±219.3%, with 80% of held-out values landing inside the 95% band.

-8%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 →
0.41Projected 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 →
0.14–0.6995% 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 →
±219.3%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 Iowa is projected to stay roughly flat through 2030, near 0.41 (95% range 0.14–0.69). A 5-year backtest shows a typical error of ±219.3%, with 80% of held-out values landing inside the 95% band.19672030
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 →
20260.400.130.68
20270.410.130.68
20280.410.130.68
20290.410.140.69
20300.410.140.69

Red-eyed Vireo Survey Routes in Iowa

Routes recording Red-eyed Vireo in Iowa.
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 →
Washta520141972
Desmoines319681968
Dinsdale320251983
Clare320191990
Mccallsburg320192019
Mt Hamill220251969
Red Rock220251969
Exline120251983
Melrose120061978
Bedford120132013
Burchinal120062000
Bryant120241975
West Liberty120141968
Cedar Valley119951973
Brooklyn120222004
Williamsburg120171972
Panther120211967
Washington120251975
Neola120021978
Wales120181967
Maquoketa120251984
Alice119991974
Prairieburg119901972
Hudson120251968
Kanawha119821982

Red-eyed Vireo Population Trend in Other States

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

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