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

Common Grackle Population Trend in Wisconsin

All statesGeneralists

Common Grackle in Wisconsin has fallen sharply: down 59% on the route-weighted index since 1968.

-59%Since 1968
98Routes In State
58Years

Notable Common Grackle Trends in Wisconsin

long arc declinecomputed index

Common Grackle has fallen sharply in Wisconsin: down 59% on the route-weighted index since 1968.

Common Grackle Population Forecast in Wisconsin

If the recent trend holds, Common Grackle in Wisconsin is projected to fall about 45% by 2029 — from 16 in 2024 to a central estimate of 9.0 (95% range 0.00–26). A 5-year backtest shows a typical error of ±20.6%, with 100% of held-out values landing inside the 95% band.

-45%Change by 2029
9.0Projected 2029 index
0.00–2695% range
±20.6%Backtest error
19662029
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
2025120.0029
2026110.0029
2027110.0028
20289.80.0027
20299.00.0026

Common Grackle Survey Routes in Wisconsin

Routes recording Common Grackle in Wisconsin.
Kiel10620221998
Omro8220011966
Mount Horeb7819901967
Pt Washingtn7620241966
Weyerhauser7520241966
Annaton6020241998
Raymond5220241966
Grimms5220211998
Stratford4320241966
Viroqua4220241966
Mukwonago4120041998
Verona4020241991
Brownsville3720241966
Eden3720241966
Holland3520241998
Hazel Green3420241966
Manitowoc3220241966
Hebron3220241966
Hudson3120241966
Trempealeau3120241966
Beloit2720241998
Stetsonville2420241990
Meridean2420241999
Newburg Crns2320241966
N Andover2320241967

Common Grackle Population Trend in Other States

alabamaarkansascoloradoconnecticutdelawarefloridageorgiaidahoillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomapennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasutahvermontvirginiawest-virginiawyoming

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