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

Common Grackle Population Trend in Montana

All statesGeneralists

Common Grackle in Montana has surged: up 178% on the route-weighted index since 1970.

+178%Since 1970
75Routes In State
56Years

Notable Common Grackle Trends in Montana

long arc increasecomputed index

Common Grackle has surged in Montana: up 178% on the route-weighted index since 1970.

Common Grackle Population Forecast in Montana

If the recent trend holds, Common Grackle in Montana is projected to fall about 48% by 2029 — from 6.2 in 2024 to a central estimate of 3.3 (95% range 0.59–6.0). A 5-year backtest shows a typical error of ±38.3%, with 80% of held-out values landing inside the 95% band.

-48%Change by 2029
3.3Projected 2029 index
0.59–6.095% range
±38.3%Backtest error
19682029
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
20253.20.555.9
20263.20.565.9
20273.30.575.9
20283.30.585.9
20293.30.596.0

Common Grackle Survey Routes in Montana

Routes recording Common Grackle in Montana.
Westby7620242015
Glasgow5620241968
Harlem4520211968
Glentana3920242015
Lambert3220242021
Custer 22820242024
Webster2620241979
Miles City2620242015
Redstone2020241975
Chinook2020242015
Church Hill2020242017
St Xavier1620111979
Winifred1620232023
Sun River1520192016
Lindsay1220242015
Saco1120242015
Wolf Point1120242015
Custer1120222019
Great Falls1020241972
Reed Point1020241977
Albion1020241982
St Mary919711971
Cleveland920241985
Powderville920241970
Gildford920242018

Common Grackle Population Trend in Other States

alabamaarkansascoloradoconnecticutdelawarefloridageorgiaidahoillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourinebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomapennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasutahvermontvirginiawest-virginiawisconsinwyoming

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