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

Clapper Rail In Gulf Coastal Prairie

All regionsGulf Coastal PrairieWetland birds

Clapper Rail in Gulf Coastal Prairie has fallen sharply: down 68% on the route-weighted index since 1969.

-68%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 →
21Routes 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 →
55YearsYears 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 →

Clapper Rail has fallen sharply in Gulf Coastal Prairie: down 68% on the route-weighted index since 1969.

Forecast

If the recent trend holds, Clapper Rail in Gulf Coastal Prairie is projected to stay roughly flat through 2029, near 0.99 (95% range 0.00–2.4). A 5-year backtest shows a typical error of ±30.6%, with 100% of held-out values landing inside the 95% band.

+10%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 →
0.99Projected 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 →
0.00–2.495% 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 →
±30.6%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, Clapper Rail in Gulf Coastal Prairie is projected to stay roughly flat through 2029, near 0.99 (95% range 0.00–2.4). A 5-year backtest shows a typical error of ±30.6%, 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 →
20250.990.002.4
20260.990.002.4
20270.990.002.4
20280.990.002.4
20290.990.002.4

Routes In Gulf Coastal Prairie

Routes recording Clapper Rail 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 →
Ltl ChenierLOUISIANA162024
Grand IsleLOUISIANA102019
Sabine Nwr 2LOUISIANA102016
Sabine NwrLOUISIANA82001
Gran ChenierLOUISIANA61982
Forked Island 2LOUISIANA52011
CreoleLOUISIANA41980
Forked IslandLOUISIANA32019
GlencoeLOUISIANA21997
EstherLOUISIANA22010
Oyster LakeTEXAS22023
HackberryLOUISIANA12012
WoodlawnLOUISIANA12017
Lag AtascosaTEXAS11972
IndianolaTEXAS12022
WinnieTEXAS11995
StowellTEXAS12017
DanburyTEXAS12024
ChinquapinTEXAS12024
Bayside 2TEXAS12004
Bayside 3TEXAS12024

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