BirdAnalyst
Species · North Dakota · BBS 2026 Release · 1966–2025

Common Grackle Population Trend in North Dakota

All statesGeneralists

Common Grackle in North Dakota has surged: up 488% on the route-weighted index since 1969.

+488%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 →
51Routes 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 Common Grackle Trends in North DakotaNotable signalsLong-arc shifts the engine flags automatically — sustained declines or increases large enough to stand out from year-to-year noise.Full methodology →

long arc increasecomputed indexTrend sourceWhether the figure is our own computed route-weighted index or an official USGS modeled estimate. The current build labels every trend as computed.Full methodology →

Common Grackle has surged in North Dakota: up 488% on the route-weighted index since 1969.

Common Grackle Population Forecast in North Dakota

If the recent trend holds, Common Grackle in North Dakota is projected to stay roughly flat through 2030, near 101 (95% range 76–125). A 5-year backtest shows a typical error of ±16.1%, with 80% of held-out values landing inside the 95% band.

-3%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 →
101Projected 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 →
76–12595% 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 →
±16.1%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, Common Grackle in North Dakota is projected to stay roughly flat through 2030, near 101 (95% range 76–125). A 5-year backtest shows a typical error of ±16.1%, with 80% 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 →
20269671120
20279773121
20289874122
20299975124
203010176125

Common Grackle Survey Routes in North Dakota

Routes recording Common Grackle in North Dakota.
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 →
Edgeley23120251980
Buchanan22220251967
Wimbledon21520251981
Glen Ullin20520251982
Horsehead Lk19020251980
Sheyenne Lk16120251980
Lakota 215020252010
Bowman14620251967
Denbigh14520251968
Webster13520241989
Forman13220251968
Montpelier12820251990
Niles12220251989
Douglas Crk12120251982
Danzig 210920252019
Braddock9820231988
Rolla9220241969
Dickinson9220251968
Lake George8620231967
Zap8320241967
Loraine8220191982
Abercrombie7920121967
Cooperstown7320251969
Regan6920251968
Carpio6820231967

Common Grackle Population Trend in Other States

alabamaarkansascoloradoconnecticutdelawarefloridageorgiaidahoillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinaohiooklahomapennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasutahvermontvirginiawest-virginiawisconsinwyoming

Source: USGS North American Breeding Bird Survey, retrieved 2026-08-14.