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

European Starling Population Trend in Iowa

All statesGeneralists

European Starling in Iowa has edged down: down 24% on the route-weighted index since 1969.

-24%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 →
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 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 rise about 18% by 2030 — from 28 in 2025 to a central estimate of 33 (95% range 13–53). A 5-year backtest shows a typical error of ±28.3%, with 100% of held-out values landing inside the 95% band.

+18%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 →
33Projected 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 →
13–5395% 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 →
±28.3%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, European Starling in Iowa is projected to rise about 18% by 2030 — from 28 in 2025 to a central estimate of 33 (95% range 13–53). A 5-year backtest shows a typical error of ±28.3%, with 100% 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 →
2026351555
2027341554
2028341454
2029331453
2030331353

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 →
Desmoines14819791968
Mt Hamill9920251967
Panther8220251967
Cedar Valley7519971967
Red Rock7420251968
Hudson7220251967
College Spgs6920041967
Sioux City6520251968
Garner6119931971
Neola5320251968
Zearing4519951967
Scranton4220251967
Mccallsburg4020251996
Brooklyn3920221967
Festina3520251968
Washington3120251967
Alice3019991967
Bryant2920251967
Rock Valley2920251968
Pierson2620251968
Maquoketa2520251967
Clare2220191967
West Liberty1820251968
College Spgs 21820232005
Melrose1720251974

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 2026-08-14.