BirdAnalyst
Species · Alabama · BBS 2025 Release · 1966–2024

Great Blue Heron Population Trend in Alabama

All statesWetland birds

Great Blue Heron in Alabama has surged: up 259% on the route-weighted index since 1968.

+259%Since 1968TrendPercent 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 →
106Routes 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 Great Blue Heron Trends in AlabamaNotable 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 Alabama: up 259% on the route-weighted index since 1968.

Great Blue Heron Population Forecast in Alabama

If the recent trend holds, Great Blue Heron in Alabama is projected to rise about 275% by 2029 — from 0.81 in 2024 to a central estimate of 3.0 (95% range 1.5–4.6). A 5-year backtest shows a typical error of ±143.6%, with 20% of held-out values landing inside the 95% band.

+275%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 →
3.0Projected 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 →
1.5–4.695% 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 →
±143.6%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 Alabama is projected to rise about 275% by 2029 — from 0.81 in 2024 to a central estimate of 3.0 (95% range 1.5–4.6). A 5-year backtest shows a typical error of ±143.6%, with 20% of held-out values landing inside the 95% band.19662029
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 →
20252.81.34.4
20262.91.44.4
20272.91.44.5
20283.01.44.5
20293.01.54.6

Great Blue Heron Survey Routes in Alabama

Routes recording Great Blue Heron in Alabama.
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 →
Wheeler Dam11420231993
Riverside4120131999
Triana1820121999
Alabama Pt 21520192004
Alabama Pt1320031966
Dauphin Is1119901970
Greensport720241988
Billingsley520221968
Valhermoso Spg 2520142014
Stevenson520241996
Dauphin Is 3520212021
Guntersville420171986
Talladega420241996
Summitt319781968
Liberty320221975
Riderwood320171966
Courtland320211997
Brooksville320231988
Dauphin Is 2320191991
Autaugaville320081996
Sprott-Cahaba Riv320141999
Gainestown Ferry320151999
Chacaloochee Bay320192009
St Florian220241991
Valhermoso Spgs220101970

Great Blue Heron Population Trend in Other States

alaskaarizonaarkansascaliforniacoloradoconnecticutdelawarefloridageorgiaidahoillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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