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

Grasshopper Sparrow Population Trend in Iowa

All statesGrassland birds

Grasshopper Sparrow in Iowa has collapsed: down 94% on the route-weighted index since 1969.

-94%Since 1969
39Routes In State
57Years

Notable Grasshopper Sparrow Trends in Iowa

long arc declinecomputed index

Grasshopper Sparrow has collapsed in Iowa: down 94% on the route-weighted index since 1969.

Grasshopper Sparrow Population Forecast in Iowa

If the recent trend holds, Grasshopper Sparrow in Iowa is projected to fall about 100% by 2029 — from 0.50 in 2024 to a central estimate of 0.00 (95% range 0.00–3.3). A 5-year backtest shows a typical error of ±108.1%, with 100% of held-out values landing inside the 95% band.

-100%Change by 2029
0.00Projected 2029 index
0.00–3.395% range
±108.1%Backtest error
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 index95% low95% high
20250.000.003.3
20260.000.003.3
20270.000.003.3
20280.000.003.3
20290.000.003.3

Grasshopper Sparrow Survey Routes in Iowa

Routes recording Grasshopper Sparrow in Iowa.
Bedford1520181968
Zearing1019951967
College Spgs720041967
Garner519901971
Cedar Valley419971967
Alice419991972
Festina420241968
Melrose320231974
Bryant320241967
Prairieburg320181969
Mt Hamill220181967
Desmoines219741968
Neola220141968
Wales220181967
Maquoketa220241967
Dinsdale220151968
Clare220171967
Pierson220131968
Burchinal220242024
College Spgs 2220232005
Exline120231974
West Liberty120181968
Brooklyn120211967
Williamsburg120231967
Red Rock120231968

Grasshopper Sparrow Population Trend in Other States

alabamaarizonaarkansascaliforniacoloradoconnecticutdelawarefloridageorgiaidahoillinoisindianakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniasouth-carolinasouth-dakotatennesseetexasutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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