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

Great Blue Heron Population Trend in North Dakota

All statesWetland birds

Great Blue Heron in North Dakota has surged: up 224% on the route-weighted index since 1969.

+224%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 →
45Routes 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 Great Blue Heron 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 →

Great Blue Heron has surged in North Dakota: up 224% on the route-weighted index since 1969.

Great Blue Heron Population Forecast in North Dakota

If the recent trend holds, Great Blue Heron in North Dakota is projected to rise about 36% by 2029 — from 0.44 in 2024 to a central estimate of 0.61 (95% range 0.26–0.95). A 5-year backtest shows a typical error of ±21.3%, with 100% of held-out values landing inside the 95% band.

+36%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 →
0.61Projected 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 →
0.26–0.9595% 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 →
±21.3%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, Great Blue Heron in North Dakota is projected to rise about 36% by 2029 — from 0.44 in 2024 to a central estimate of 0.61 (95% range 0.26–0.95). A 5-year backtest shows a typical error of ±21.3%, 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 →
20250.580.230.92
20260.580.230.93
20270.590.240.94
20280.600.250.95
20290.610.260.95

Great Blue Heron Survey Routes in North Dakota

Routes recording Great Blue Heron 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 →
Regan620141984
Cooperstown420241969
Carson320231992
Emerado320231978
Ft Yates320031974
Danzig220061988
Wimbledon220221991
Buchanan220241973
Carpio220231974
Bowman220241987
Douglas Crk220211986
Danzig 2220222022
Forman120231971
Edgeley120241992
Lake George120021980
Kempton120051993
Horsehead Lk120241996
Nash119941991
Lakota120081972
Webster120002000
Rolla120191975
Niles120002000
Dickinson120211980
Dunn Center120221969
Loraine120181986

Great Blue Heron Population Trend in Other States

alabamaalaskaarizonaarkansascaliforniacoloradoconnecticutdelawarefloridageorgiaidahoillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinaohiooklahomaoregonpennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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