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

Blue-winged Teal Population Trend in North Dakota

All statesWaterfowl

Blue-winged Teal in North Dakota has surged: up 173% on the route-weighted index since 1969.

+173%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 →
50Routes 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 Blue-winged Teal 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 →

Blue-winged Teal has surged in North Dakota: up 173% on the route-weighted index since 1969.

Blue-winged Teal Population Forecast in North Dakota

If the recent trend holds, Blue-winged Teal in North Dakota is projected to stay roughly flat through 2029, near 21 (95% range 11–32). A 5-year backtest shows a typical error of ±21.8%, with 100% of held-out values landing inside the 95% band.

-7%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 →
21Projected 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 →
11–3295% 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 →
±21.8%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, Blue-winged Teal in North Dakota is projected to stay roughly flat through 2029, near 21 (95% range 11–32). A 5-year backtest shows a typical error of ±21.8%, with 100% 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 →
2025201031
2026211131
2027211131
2028211131
2029211132

Blue-winged Teal Survey Routes in North Dakota

Routes recording Blue-winged Teal 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 →
Wild Rose10420241982
Wimbledon7420241981
Horsehead Lk6520241980
Niles6220241989
Danzig 25020242019
Sheyenne Lk4620241980
Danzig4320141982
Lakota 24120242010
Braddock3920221988
Lakota3820091968
Montpelier3320241990
Buchanan3120241967
Carpio3120231969
Forman2820241968
Sydney2819831968
Lake George2120221967
Bowman1720241967
Cooperstown1520241969
Rolla1220241969
Parshall1220131982
Webster1120241991
Edgeley920241980
Regan720221968
Lark519821969
Gorham520181968

Blue-winged Teal Population Trend in Other States

alabamaalaskaarizonaarkansascaliforniacoloradodelawarefloridaidahoillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanevadanew-hampshirenew-mexiconew-yorkohiooklahomaoregonpennsylvaniarhode-islandsouth-dakotatennesseetexasutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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