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Species · Texas · BBS 2026 Release · 1966–2025

Black-bellied Whistling-Duck Population Trend in Texas

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Black-bellied Whistling-Duck in Texas has surged: up 481% on the route-weighted index since 1969.

+481%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 →
113Routes In StateSurvey 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 Black-bellied Whistling-Duck Trends in TexasNotable 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 →

Black-bellied Whistling-Duck has surged in Texas: up 481% on the route-weighted index since 1969.

Black-bellied Whistling-Duck Population Forecast in Texas

If the recent trend holds, Black-bellied Whistling-Duck in Texas is projected to rise about 55% by 2030 — from 2.1 in 2025 to a central estimate of 3.3 (95% range 1.3–5.3). A 5-year backtest shows a typical error of ±35.5%, with 100% of held-out values landing inside the 95% band.

+55%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 →
3.3Projected 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 →
1.3–5.395% 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 →
±35.5%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, Black-bellied Whistling-Duck in Texas is projected to rise about 55% by 2030 — from 2.1 in 2025 to a central estimate of 3.3 (95% range 1.3–5.3). A 5-year backtest shows a typical error of ±35.5%, with 100% 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 →
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Black-bellied Whistling-Duck Survey Routes in Texas

Routes recording Black-bellied Whistling-Duck in Texas.
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 →
Indianola6220241967
Heidelberg6120242013
Pedro Creek5420051999
Loyola Beach4020091994
Port Acres3820252009
Bayside 23520041997
Lag Atascosa3420251969
Moon Lake 23120252012
Winnie2820251995
Bayside 32720242005
Raymondville2620251969
Progreso2620111994
Katy2520251977
Kingsville1820241967
Danbury1520251984
La Pryor1420172001
Oyster Lake1220251995
Petronila1120251968
Stowell1120251988
Lone Oak1120221970
Brite1120251994
L. Atascosa Nwr1020251998
Loyola Beach 21020252010
Chinquapin920251995
Creedmore720141995

Black-bellied Whistling-Duck Population Trend in Other States

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