BirdAnalyst
Species · North Dakota · BBS 2025 Release · 1966–2024

Common Grackle Population Trend in North Dakota

All statesGeneralists

Common Grackle in North Dakota has surged: up 477% on the route-weighted index since 1969.

+477%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 →
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 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 476% 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 fall about 15% by 2029 — from 116 in 2024 to a central estimate of 99 (95% range 74–123). A 5-year backtest shows a typical error of ±16.2%, with 80% of held-out values landing inside the 95% band.

-15%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 →
99Projected 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 →
74–12395% 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 →
±16.2%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 fall about 15% by 2029 — from 116 in 2024 to a central estimate of 99 (95% range 74–123). A 5-year backtest shows a typical error of ±16.2%, with 80% 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 →
20259469118
20269571120
20279672121
20289873122
20299974123

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 →
Douglas Crk32220241982
Edgeley29920241980
Wimbledon27120241981
Horsehead Lk24320241980
Montpelier19420241990
Braddock16620221988
Buchanan15420241967
Sheyenne Lk15420241980
Danzig 214120242019
Webster13520241989
Cooperstown12720241969
Denbigh12720241968
Bowman12220241967
Niles12020241989
Lakota 211620242010
Lake George9220221967
Rolla9220241969
Zap8320241967
Loraine8220191982
Abercrombie7920121967
Dickinson7320241968
Forman7220241968
Carpio6820231967
Powers Lake6120241980
Solen6120242005

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 2026-05-22.