BirdAnalyst
Species · BCR 27 · BBS 2025 Release · 1966–2024

Tricolored Heron In Southeastern Coastal Plain

All regionsSoutheastern Coastal PlainWetland birds

Tricolored Heron in Southeastern Coastal Plain has collapsed: down 87% on the route-weighted index since 1968.

-87%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 →
67Routes 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 →
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 SignalsNotable 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 →

Tricolored Heron has collapsed in Southeastern Coastal Plain: down 87% on the route-weighted index since 1968.

Tricolored Heron In Southeastern Coastal Plain Population Forecast

If the recent trend holds, Tricolored Heron in Southeastern Coastal Plain is projected to fall about 19% by 2029 — from 0.06 in 2024 to a central estimate of 0.05 (95% range 0.00–0.23). A 5-year backtest shows a typical error of ±78.4%, with 100% of held-out values landing inside the 95% band.

-19%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 →
0.05Projected 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 →
0.00–0.2395% 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 →
±78.4%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, Tricolored Heron in Southeastern Coastal Plain is projected to fall about 19% by 2029 — from 0.06 in 2024 to a central estimate of 0.05 (95% range 0.00–0.23). A 5-year backtest shows a typical error of ±78.4%, 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 →
20250.060.000.23
20260.060.000.23
20270.060.000.23
20280.050.000.23
20290.050.000.23

Routes In Southeastern Coastal Plain

Routes recording Tricolored Heron 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 →
Myrtle GroveNORTH-CAROLINA52024
Kiawah IslandSOUTH-CAROLINA42024
StocktonGEORGIA32007
Port St JoeFLORIDA22014
Santa RosaFLORIDA21995
St Vincent IFLORIDA22024
NashvilleGEORGIA21990
Holly HillSOUTH-CAROLINA21980
WalterboroSOUTH-CAROLINA21975
GrangeburgALABAMA12018
Dauphin IsALABAMA11990
Alabama PtALABAMA11995
EpesALABAMA12016
Dauphin Is 2ALABAMA12015
Alabama Pt 2ALABAMA12009
Gainestown FerryALABAMA12006
Chacaloochee BayALABAMA12017
Oak GroveFLORIDA11976
Ft Waltn BchFLORIDA11975
BlountstownFLORIDA12015
Broad BranchFLORIDA11998
MiccosukeeFLORIDA12021
CovingtonFLORIDA11979
SteinhatcheeFLORIDA12005
BelmontFLORIDA11974

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