BirdAnalyst
Species · BCR 27 · BBS 2026 Release · 1966–2025

Least Bittern In Southeastern Coastal Plain

All regionsSoutheastern Coastal PlainWetland birds

Least Bittern in Southeastern Coastal Plain has collapsed: down 78% on the route-weighted index since 1969.

-78%Since 1969TrendPercent 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 →
27Routes In RegionSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
51YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable SignalsNotable 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 Least Bittern in Southeastern Coastal Plain. See the full index history below.

Least Bittern In Southeastern Coastal Plain Population Forecast

If the recent trend holds, Least Bittern in Southeastern Coastal Plain is projected to stay roughly flat through 2030, near 0.03 (95% range 0.00–0.07). A 5-year backtest shows a typical error of ±417.5%, with 100% of held-out values landing inside the 95% band.

n/aChange 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 →
0.03Projected 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 →
0.00–0.0795% 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 →
±417.5%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, Least Bittern in Southeastern Coastal Plain is projected to stay roughly flat through 2030, near 0.03 (95% range 0.00–0.07). A 5-year backtest shows a typical error of ±417.5%, with 100% of held-out values landing inside the 95% band.19662030
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 →
20260.030.000.07
20270.030.000.07
20280.030.000.07
20290.030.000.07
20300.030.000.07

Routes In Southeastern Coastal Plain

Routes recording Least Bittern in Southeastern Coastal Plain.
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 →
LovedaleFLORIDA42011
Alabama PtALABAMA31990
MashoesNORTH-CAROLINA21975
KinstonNORTH-CAROLINA22001
BillingsleyALABAMA12001
GrangeburgALABAMA12002
BrantleyALABAMA11973
Dauphin IsALABAMA11977
WhitehallALABAMA12021
Alabama Pt 2ALABAMA12007
Gainestown FerryALABAMA12003
Chacaloochee BayALABAMA12019
Port St JoeFLORIDA12008
SteinhatcheeFLORIDA11993
St Vincent IFLORIDA12025
DarienGEORGIA12019
NashvilleGEORGIA12016
LacombeLOUISIANA11969
Mt CarmelMISSISSIPPI12002
LatimerMISSISSIPPI12015
MerrimonNORTH-CAROLINA12012
Myrtle GroveNORTH-CAROLINA12003
SpeedNORTH-CAROLINA11981
SupplyNORTH-CAROLINA12006
Jarvisburg 2NORTH-CAROLINA12022

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