BirdAnalyst
Species · Wyoming · BBS 2025 Release · 1966–2024

Gadwall Population Trend in Wyoming

All statesWaterfowl

Gadwall in Wyoming has surged: up 167% on the route-weighted index since 1971.

+167%Since 1971TrendPercent 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 →
67Routes 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 →
54YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Gadwall Trends in WyomingNotable 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 →

Gadwall has surged in Wyoming: up 167% on the route-weighted index since 1971.

Gadwall Population Forecast in Wyoming

If the recent trend holds, Gadwall in Wyoming is projected to rise about 80% by 2029 — from 0.53 in 2024 to a central estimate of 0.95 (95% range 0.00–2.2). A 5-year backtest shows a typical error of ±155.4%, with 100% of held-out values landing inside the 95% band.

+80%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 →
0.95Projected 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 →
0.00–2.295% 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 →
±155.4%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, Gadwall in Wyoming is projected to rise about 80% by 2029 — from 0.53 in 2024 to a central estimate of 0.95 (95% range 0.00–2.2). A 5-year backtest shows a typical error of ±155.4%, with 100% of held-out values landing inside the 95% band.19682029
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 →
20250.920.002.2
20260.930.002.2
20270.930.002.2
20280.940.002.2
20290.950.002.2

Gadwall Survey Routes in Wyoming

Routes recording Gadwall in Wyoming.
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 →
Rock River9920221991
Rozet1520172017
Brookhurst1120131968
Yellowstone820221987
Seedskadee820161994
Harmony820221982
Clarkelen719751971
Bill719991993
Rawlins 2720172016
Bucknum720241993
Natrona619901969
Sussex620241992
Green River619841977
Wyarno520241975
Kaycee520222022
Sybille Cyn520142014
Hayden Val419861986
Buford420242019
Carter 2420242019
Crowheart420042004
Newcastle420241988
Walcott420211982
Fontenelle320241989
Recluse320221991
Seely319981990

Gadwall Population Trend in Other States

alaskaarizonacaliforniacoloradodelawareidahoillinoisiowakansasmassachusettsmichiganminnesotamissourimontananebraskanevadanew-jerseynew-mexiconew-yorknorth-dakotaoklahomaoregonpennsylvaniarhode-islandsouth-dakotatexasutahvermontwashingtonwisconsin

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