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

Gadwall Population Trend in Minnesota

All statesWaterfowl

Gadwall in Minnesota has declined: down 29% on the route-weighted index since 1978.

-29%Since 1978TrendPercent 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 StateSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
38YearsYears 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 MinnesotaNotable signalsLong-arc shifts the engine flags automatically — sustained declines or increases large enough to stand out from year-to-year noise.Full methodology →

No notable trend signals for Gadwall in Minnesota. See the full index history below.

Gadwall Population Forecast in Minnesota

If the recent trend holds, Gadwall in Minnesota is projected to fall about 42% by 2029 — from 0.11 in 2024 to a central estimate of 0.06 (95% range 0.00–0.36). A 5-year backtest shows a typical error of ±270.7%, with 100% of held-out values landing inside the 95% band.

-42%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 →
0.06Projected 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 →
0.00–0.3695% 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 →
±270.7%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 Minnesota is projected to fall about 42% by 2029 — from 0.11 in 2024 to a central estimate of 0.06 (95% range 0.00–0.36). A 5-year backtest shows a typical error of ±270.7%, with 100% of held-out values landing inside the 95% band.19742029
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 →
20250.070.000.36
20260.070.000.36
20270.070.000.36
20280.060.000.36
20290.060.000.36

Gadwall Survey Routes in Minnesota

Routes recording Gadwall in Minnesota.
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 →
Tenney420151990
Glenwood320011993
Ash Creek219941994
Courtland219851978
Redwood Fall220082008
Osseo220012001
Appleton220241981
Gluek219901990
Chokio220241979
Glyndon220241990
Beltrami219781978
Lake Bronson220032003
New London220001994
Chokio North220102010
Lakeville119911991
Big Stone120081995
Dawson120061974
Erie119931984
Grygla119921983
Tracy120192006
Greenbush120072004

Gadwall Population Trend in Other States

alaskaarizonacaliforniacoloradodelawareidahoillinoisiowakansasmassachusettsmichiganmissourimontananebraskanevadanew-jerseynew-mexiconew-yorknorth-dakotaoklahomaoregonpennsylvaniarhode-islandsouth-dakotatexasutahvermontwashingtonwisconsinwyoming

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