BirdAnalyst
Species · BCR 37 · BBS 2025 Release · 1966–2024

Great Blue Heron In Gulf Coastal Prairie

All regionsGulf Coastal PrairieWetland birds

Great Blue Heron in Gulf Coastal Prairie has risen sharply: up 59% on the route-weighted index since 1969.

+59%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 →
48Routes 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 →
57YearsYears 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 increasecomputed 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 →

Great Blue Heron has risen sharply in Gulf Coastal Prairie: up 59% on the route-weighted index since 1969.

Great Blue Heron In Gulf Coastal Prairie Population Forecast

If the recent trend holds, Great Blue Heron in Gulf Coastal Prairie is projected to rise about 24% by 2029 — from 2.0 in 2024 to a central estimate of 2.5 (95% range 0.91–4.2). A 5-year backtest shows a typical error of ±55.4%, with 100% of held-out values landing inside the 95% band.

+24%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 →
2.5Projected 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 →
0.91–4.295% 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 →
±55.4%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, Great Blue Heron in Gulf Coastal Prairie is projected to rise about 24% by 2029 — from 2.0 in 2024 to a central estimate of 2.5 (95% range 0.91–4.2). A 5-year backtest shows a typical error of ±55.4%, with 100% of held-out values landing inside the 95% band.19672029
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 →
20252.50.904.1
20262.50.904.2
20272.50.904.2
20282.50.914.2
20292.50.914.2

Routes In Gulf Coastal Prairie

Routes recording Great Blue Heron in Gulf Coastal Prairie.
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 →
Gran ChenierLOUISIANA151982
MauriceLOUISIANA82024
Ville PlatteLOUISIANA72019
Ltl Chenier 2LOUISIANA72011
Bayside 2TEXAS72004
RichardLOUISIANA62024
WoodlawnLOUISIANA62021
Lag AtascosaTEXAS62024
Padre Island PaisTEXAS52015
HackberryLOUISIANA42016
Grand IsleLOUISIANA42019
Bayside 3TEXAS42024
Sabine Nwr 2LOUISIANA32017
Forked IslandLOUISIANA32024
Vinton 2LOUISIANA32024
Forked Island 2LOUISIANA32011
WinnieTEXAS32023
StowellTEXAS32023
Loyola BeachTEXAS32009
ChinquapinTEXAS32024
Oyster LakeTEXAS32024
Moon LakeTEXAS32011
Loyola Beach 2TEXAS32023
L. Atascosa NwrTEXAS32023
LafitteLOUISIANA21991

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