BirdAnalyst
Species · New Mexico · BBS 2025 Release · 1966–2024

Gadwall Population Trend in New Mexico

All statesWaterfowl

Gadwall in New Mexico has held roughly steady: down 2% on the route-weighted index since 1978.

-2%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 →
13Routes 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 →
35YearsYears 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 New MexicoNotable 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 New Mexico. See the full index history below.

Gadwall Population Forecast in New Mexico

If the recent trend holds, Gadwall in New Mexico is projected to stay roughly flat through 2029, near 0.18 (95% range 0.00–0.39). A 5-year backtest shows a typical error of ±98.6%, with 100% of held-out values landing inside the 95% band.

-9%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 →
0.18Projected 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 →
0.00–0.3995% 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 →
±98.6%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 New Mexico is projected to stay roughly flat through 2029, near 0.18 (95% range 0.00–0.39). A 5-year backtest shows a typical error of ±98.6%, with 100% of held-out values landing inside the 95% band.19732029
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 →
20250.180.000.39
20260.180.000.39
20270.180.000.39
20280.180.000.39
20290.180.000.39

Gadwall Survey Routes in New Mexico

Routes recording Gadwall in New Mexico.
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 →
Stinking Lk.1019961992
Grenville619791977
Clovis520132013
Dulce520242000
Capulin419931993
Wagon Mound419731973
Angel Fire 2420242005
Maxwell420132002
Gallinas420122012
Angel Fire220021993
Laborcita120021994
La Plata120122012
Red Rock119931992

Gadwall Population Trend in Other States

alaskaarizonacaliforniacoloradodelawareidahoillinoisiowakansasmassachusettsmichiganminnesotamissourimontananebraskanevadanew-jerseynew-yorknorth-dakotaoklahomaoregonpennsylvaniarhode-islandsouth-dakotatexasutahvermontwashingtonwisconsinwyoming

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