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Species · Alabama · BBS 2026 Release · 1966–2025

Black-crowned Night Heron Population Trend in Alabama

All statesWetland birds

Black-crowned Night Heron in Alabama has surged: up 276% on the route-weighted index since 1972.

+276%Since 1972TrendPercent 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 →
17Routes 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 →
28YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Black-crowned Night 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 →

No notable trend signals for Black-crowned Night Heron in Alabama. See the full index history below.

Black-crowned Night Heron Population Forecast in Alabama

If the recent trend holds, Black-crowned Night Heron in Alabama is projected to fall about 45% by 2030 — from 0.16 in 2025 to a central estimate of 0.09 (95% range 0.02–0.16). A 5-year backtest shows a typical error of ±54.7%, with 40% of held-out values landing inside the 95% band.

-45%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 →
0.09Projected 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 →
0.02–0.1695% 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 →
±54.7%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, Black-crowned Night Heron in Alabama is projected to fall about 45% by 2030 — from 0.16 in 2025 to a central estimate of 0.09 (95% range 0.02–0.16). A 5-year backtest shows a typical error of ±54.7%, with 40% of held-out values landing inside the 95% band.19672030
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 →
20260.080.010.15
20270.080.010.15
20280.090.010.15
20290.090.020.16
20300.090.020.16

Black-crowned Night Heron Survey Routes in Alabama

Routes recording Black-crowned Night 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 Dam720252011
Valhermoso Spgs319751975
Drummond220072007
Seale220012001
St Florian119671967
Mclellan119891989
Nixburg 2120012001
Pine Grove120251992
Dauphin Is119761976
Dauphin Is 2120172001
Greensport120052005
Triana120042004
Greensboro120152015
Wallsboro120162016
Warrior Std119851970
Kymulga120042004
Grangeburg119821972

Black-crowned Night Heron Population Trend in Other States

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

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