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

Green Heron Population Trend in Alabama

All statesWetland birds

Green Heron in Alabama has fallen sharply: down 54% on the route-weighted index since 1968.

-54%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 Green 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 declinecomputed 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 →

Green Heron has fallen sharply in Alabama: down 54% on the route-weighted index since 1968.

Green Heron Population Forecast in Alabama

If the recent trend holds, Green Heron in Alabama is projected to stay roughly flat through 2029, near 0.45 (95% range 0.00–1.1). A 5-year backtest shows a typical error of ±118.2%, with 100% of held-out values landing inside the 95% band.

-8%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 →
0.45Projected 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 →
0.00–1.195% 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 →
±118.2%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, Green Heron in Alabama is projected to stay roughly flat through 2029, near 0.45 (95% range 0.00–1.1). A 5-year backtest shows a typical error of ±118.2%, with 100% 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 →
20250.500.001.1
20260.490.001.1
20270.480.001.1
20280.460.001.1
20290.450.001.1

Green Heron Survey Routes in Alabama

Routes recording Green 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 →
Pine Grove420241968
Woodville420181997
Chacaloochee Bay420192009
Hillsboro319961969
Greensport320241967
Howard320191966
Calebee320231995
Valhermoso Spg 2320142014
Triana320122000
Swaim220141971
Dearmanville219831966
Smyer Lake220211967
Mt Olive220241966
Warrior Std220241966
Cottonton220211966
Newton219981998
Brantley220081968
South220091966
Alabama Pt220011966
Foley219821972
Blocton220161969
Guntersville220161980
Childersburg219981985
Youngtown220161994
Mt. Gilead220101995

Green Heron Population Trend in Other States

arizonaarkansascaliforniaconnecticutdelawarefloridageorgiaillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourinebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasvermontvirginiawashingtonwest-virginiawisconsin

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