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

Anhinga Population Trend in Alabama

All statesGeneralists

Anhinga in Alabama has increased: up 43% on the route-weighted index since 1978.

+43%Since 1978TrendPercent 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 →
19Routes 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 →
31YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Anhinga 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 Anhinga in Alabama. See the full index history below.

Anhinga Population Forecast in Alabama

If the recent trend holds, Anhinga in Alabama is projected to rise about 23% by 2029 — from 0.05 in 2024 to a central estimate of 0.07 (95% range 0.00–0.15). A 5-year backtest shows a typical error of ±53.5%, with 60% of held-out values landing inside the 95% band.

+23%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 →
0.07Projected 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 →
0.00–0.1595% 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 →
±53.5%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, Anhinga in Alabama is projected to rise about 23% by 2029 — from 0.05 in 2024 to a central estimate of 0.07 (95% range 0.00–0.15). A 5-year backtest shows a typical error of ±53.5%, with 60% of held-out values landing inside the 95% band.19722029
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 →
20250.060.000.14
20260.060.000.14
20270.060.000.14
20280.060.000.14
20290.070.000.15

Anhinga Survey Routes in Alabama

Routes recording Anhinga 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 →
Lanett620222022
Madrid420191994
Wallsboro220041999
Fairview220241992
Harrell119861972
Greensboro120002000
Billingsley120172017
Newton119981998
Grangeburg120161978
Brundidge120152015
Brantley120232023
Mclellan120092009
Millry120012001
Elamville120082008
Calebee120192019
Helicon120242024
St. Elmo120172017
Gainestown Ferry120091999
Chacaloochee Bay120192009

Anhinga Population Trend in Other States

arkansasfloridageorgialouisianamississippinorth-carolinaoklahomasouth-carolinatexasvirginia

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