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

Ring-billed Gull In Gulf Coastal Prairie

All regionsGulf Coastal PrairieWetland birds

Ring-billed Gull in Gulf Coastal Prairie has collapsed: down 77% on the route-weighted index since 1973.

-77%Since 1973TrendPercent 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 →
15Routes 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 →
19YearsYears 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 →

Ring-billed Gull has collapsed in Gulf Coastal Prairie: down 77% on the route-weighted index since 1973.

Forecast

If the recent trend holds, Ring-billed Gull in Gulf Coastal Prairie is projected to fall about 96% by 2029 — from 0.14 in 2024 to a central estimate of 0.01 (95% range 0.00–0.47). A 5-year backtest shows a typical error of ±215.5%, with 100% of held-out values landing inside the 95% band.

-96%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 →
0.01Projected 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 →
0.00–0.4795% 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 →
±215.5%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, Ring-billed Gull in Gulf Coastal Prairie is projected to fall about 96% by 2029 — from 0.14 in 2024 to a central estimate of 0.01 (95% range 0.00–0.47). A 5-year backtest shows a typical error of ±215.5%, 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 →
20250.040.000.50
20260.030.000.49
20270.020.000.48
20280.010.000.48
20290.010.000.47

Routes In Gulf Coastal Prairie

Routes recording Ring-billed Gull 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 →
Padre Island PaisTEXAS82015
CreoleLOUISIANA71980
Gran ChenierLOUISIANA41981
HackberryLOUISIANA31982
Grand IsleLOUISIANA32017
Oyster LakeTEXAS32024
WinnieTEXAS21989
StowellTEXAS21981
EstherLOUISIANA11997
RichardLOUISIANA11998
Forked IslandLOUISIANA12017
IndianolaTEXAS12004
Loyola Beach 2TEXAS12014
Moon Lake 2TEXAS12021
Bayside 3TEXAS12014

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