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

American Crow Population Trend in Iowa

All statesGeneralists

American Crow in Iowa has declined: down 39% on the route-weighted index since 1969.

-39%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 American Crow 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 American Crow in Iowa. See the full index history below.

American Crow Population Forecast in Iowa

If the recent trend holds, American Crow in Iowa is projected to fall about 23% by 2030 — from 13 in 2025 to a central estimate of 9.7 (95% range 2.4–17). A 5-year backtest shows a typical error of ±14.2%, with 100% of held-out values landing inside the 95% band.

-23%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 →
9.7Projected 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 →
2.4–1795% 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 →
±14.2%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, American Crow in Iowa is projected to fall about 23% by 2030 — from 13 in 2025 to a central estimate of 9.7 (95% range 2.4–17). A 5-year backtest shows a typical error of ±14.2%, 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 →
2026113.418
2027103.118
2028102.918
202910.02.617
20309.72.417

American Crow Survey Routes in Iowa

Routes recording American Crow 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 →
Mt Hamill6220251967
Hudson5120251967
Red Rock4020251968
Zearing3119951967
Exline2520251974
Alice2519991967
Cedar Valley2319971967
Festina2220251968
Brooklyn2120251967
Melrose2020251974
Davis Corner2020251968
Garner1819931971
Bedford1620251968
Williamsburg1520231967
Wales1520251967
Dinsdale1420251968
Kanawha1220251967
Titonka1020251968
College Spgs920041967
Prairieburg920251967
College Spgs 2820252005
Neola720251968
Sioux City720241968
Burchinal720251995
Mccallsburg720251996

American Crow 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.