BirdAnalyst
Species · Wyoming · BBS 2026 Release · 1966–2025

Great Blue Heron Population Trend in Wyoming

All statesWetland birds

Great Blue Heron in Wyoming has risen sharply: up 57% on the route-weighted index since 1974.

+57%Since 1974TrendPercent 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 →
90Routes 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 →
52YearsYears 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 WyomingNotable 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 risen sharply in Wyoming: up 57% on the route-weighted index since 1974.

Great Blue Heron Population Forecast in Wyoming

If the recent trend holds, Great Blue Heron in Wyoming is projected to fall about 85% by 2030 — from 0.38 in 2025 to a central estimate of 0.06 (95% range 0.00–1.8). A 5-year backtest shows a typical error of ±33.1%, with 100% of held-out values landing inside the 95% band.

-85%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 →
0.06Projected 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 →
0.00–1.895% 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 →
±33.1%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, Great Blue Heron in Wyoming is projected to fall about 85% by 2030 — from 0.38 in 2025 to a central estimate of 0.06 (95% range 0.00–1.8). A 5-year backtest shows a typical error of ±33.1%, with 100% of held-out values landing inside the 95% band.19682030
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 →
20260.160.001.9
20270.130.001.9
20280.110.001.8
20290.080.001.8
20300.060.001.8

Great Blue Heron Survey Routes in Wyoming

Routes recording Great Blue Heron in Wyoming.
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 →
Green River1319841977
Cody1120251983
Yellowstone820251987
Lusk720001999
Wyarno620171990
Daniel619881980
Basin520171972
Yoder520251982
Seely520001992
Otto420081974
Big Sandy420081990
Soda Well320191987
Anchor320162016
Rawlins320051989
Moran320162002
Colter Bay219981994
Brookhurst220171968
Dwyer220161995
Cumberland220191988
Meeteetse220252001
Crazy Woman220142010
Arvada220161982
Recluse220161988
Alpine220241979
Mayoworth220181982

Great Blue Heron Population Trend in Other States

alabamaalaskaarizonaarkansascaliforniacoloradoconnecticutdelawarefloridageorgiaidahoillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasutahvermontvirginiawashingtonwest-virginiawisconsin

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