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Species · Texas · BBS 2025 Release · 1966–2024

Black-bellied Whistling-Duck Population Trend in Texas

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Black-bellied Whistling-Duck in Texas has surged: up 602% on the route-weighted index since 1969.

+602%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 →
111Routes 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 →
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 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 602% 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 24% by 2029 — from 2.7 in 2024 to a central estimate of 3.4 (95% range 1.3–5.4). A 5-year backtest shows a typical error of ±47.8%, 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 →
3.4Projected 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 →
1.3–5.495% 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 →
±47.8%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 24% by 2029 — from 2.7 in 2024 to a central estimate of 3.4 (95% range 1.3–5.4). A 5-year backtest shows a typical error of ±47.8%, 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 →
20253.21.25.3
20263.31.25.3
20273.31.35.3
20283.31.35.4
20293.41.35.4

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
Winnie5420241995
Pedro Creek5420051999
Loyola Beach4020091994
Lag Atascosa3520241969
Bayside 23520041997
Port Acres2820242009
Bayside 32720242005
Progreso2620111994
Kingsville1820241967
Katy1720241977
Loyola Beach 21720242010
Oyster Lake1620241995
La Pryor1420172001
George West1320231968
Stowell1220231988
Lone Oak1120221970
Raymondville1120241969
Hondo920241975
Petronila820231968
Creedmore720141995
Agua Nueva620141975
Danbury620241984
Rock Island620231969

Black-bellied Whistling-Duck Population Trend in Other States

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