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

American Crow Population Trend in Iowa

All statesGeneralists

American Crow in Iowa has declined: down 37% on the route-weighted index since 1969.

-37%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 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 21% by 2029 — from 12 in 2024 to a central estimate of 9.8 (95% range 2.4–17). A 5-year backtest shows a typical error of ±18.1%, with 100% of held-out values landing inside the 95% band.

-21%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 →
9.8Projected 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 →
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 →
±18.1%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 21% by 2029 — from 12 in 2024 to a central estimate of 9.8 (95% range 2.4–17). A 5-year backtest shows a typical error of ±18.1%, 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 →
2025113.418
2026113.218
2027102.918
2028102.718
20299.82.417

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 →
Hudson4520221967
Red Rock4120241968
Mt Hamill3820241967
Zearing3119951967
Melrose2720241974
Bedford2720181968
Festina2620241968
Alice2519991967
Dinsdale2520241968
Cedar Valley2319971967
Garner1819931971
Davis Corner1620241968
Williamsburg1520231967
Panther1520241967
College Spgs 21420232005
Brooklyn1320221967
Washta1320141967
Burchinal1320241995
Neola1220161968
Washington1120241967
Exline920241974
College Spgs920041967
Kanawha920241967
Sioux City720241968
Titonka720241968

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 2026-05-22.