BirdAnalyst
Species · BCR 37 · BBS 2026 Release · 1966–2025

Fulvous Whistling-Duck In Gulf Coastal Prairie

All regionsGulf Coastal PrairieWaterfowl

Fulvous Whistling-Duck in Gulf Coastal Prairie has surged: up 86% on the route-weighted index since 1969.

+86%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 →
38Routes 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 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 →

Fulvous Whistling-Duck has surged in Gulf Coastal Prairie: up 86% on the route-weighted index since 1969.

Fulvous Whistling-Duck In Gulf Coastal Prairie Population Forecast

If the recent trend holds, Fulvous Whistling-Duck in Gulf Coastal Prairie is projected to rise about 216% by 2030 — from 3.7 in 2025 to a central estimate of 12 (95% range 2.4–21). A 5-year backtest shows a typical error of ±148.1%, with 60% of held-out values landing inside the 95% band.

+216%Change 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 →
12Projected 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 →
2.4–2195% 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 →
±148.1%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, Fulvous Whistling-Duck in Gulf Coastal Prairie is projected to rise about 216% by 2030 — from 3.7 in 2025 to a central estimate of 12 (95% range 2.4–21). A 5-year backtest shows a typical error of ±148.1%, with 60% of held-out values landing inside the 95% band.19672030
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 →
2026111.921
2027112.021
2028122.221
2029122.321
2030122.421

Routes In Gulf Coastal Prairie

Routes recording Fulvous Whistling-Duck 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 →
WoodlawnLOUISIANA382021
BaysideTEXAS292003
L. Atascosa NwrTEXAS232025
Ltl Chenier 2LOUISIANA152011
Rock IslandTEXAS142023
Loyola Beach 2TEXAS142025
KaplanLOUISIANA132023
Ltl ChenierLOUISIANA132024
Forked Island 2LOUISIANA132011
WinnieTEXAS132025
Bayside 2TEXAS132004
MauriceLOUISIANA112024
RichardLOUISIANA102025
PetronilaTEXAS102019
StowellTEXAS102021
Goliad PrairieTEXAS102012
Ville PlatteLOUISIANA92019
KatyTEXAS62025
Moon Lake 2TEXAS62024
ChinquapinTEXAS52023
Bayside 3TEXAS52025
Sabine Nwr 2LOUISIANA42015
Sabine NwrLOUISIANA32008
Vinton 2LOUISIANA32025
Hinkles FerTEXAS32010

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