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

European Starling Population Trend in Iowa

All statesGeneralists

European Starling in Iowa has edged down: down 15% on the route-weighted index since 1969.

-15%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 →
39Routes 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 European Starling 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 European Starling in Iowa. See the full index history below.

European Starling Population Forecast in Iowa

If the recent trend holds, European Starling in Iowa is projected to fall about 35% by 2029 — from 53 in 2024 to a central estimate of 34 (95% range 14–54). A 5-year backtest shows a typical error of ±33%, with 100% of held-out values landing inside the 95% band.

-35%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 →
34Projected 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 →
14–5495% 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 →
±33%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, European Starling in Iowa is projected to fall about 35% by 2029 — from 53 in 2024 to a central estimate of 34 (95% range 14–54). A 5-year backtest shows a typical error of ±33%, with 100% of held-out values landing inside the 95% band.19672029
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 →
2025361656
2026361656
2027351555
2028351554
2029341454

European Starling Survey Routes in Iowa

Routes recording European Starling 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 →
Red Rock33820241968
Desmoines14819791968
Panther13220241967
Scranton9520241967
Tipton9120241993
Mt Hamill7620241967
Cedar Valley7519971967
College Spgs6920041967
Hudson6520221967
Garner6119931971
Bryant6020241967
Dinsdale5220241968
Mccallsburg4620241996
Zearing4519951967
Brooklyn3920221967
West Liberty3620241968
Sioux City3420241968
Gaza3320231969
Alice3019991967
Festina3020241968
Davis Corner2820241968
Rock Valley2320241968
Clare2220191967
Washta2120141967
Maquoketa2020241967

European Starling Population Trend in Other States

alabamaalaskaarizonaarkansascaliforniacoloradoconnecticutdelawarefloridageorgiaidahoillinoisindianakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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