BirdAnalyst
Species · Montana · BBS 2026 Release · 1966–2025

Mallard Population Trend in Montana

All statesWaterfowl

Mallard in Montana has edged down: down 20% on the route-weighted index since 1970.

-20%Since 1970TrendPercent 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 →
108Routes 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 Mallard Trends in MontanaNotable 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 Mallard in Montana. See the full index history below.

Mallard Population Forecast in Montana

If the recent trend holds, Mallard in Montana is projected to rise about 29% by 2030 — from 3.2 in 2025 to a central estimate of 4.1 (95% range 0.38–7.8). A 5-year backtest shows a typical error of ±35.5%, with 100% of held-out values landing inside the 95% band.

+29%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 →
4.1Projected 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 →
0.38–7.895% 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, Mallard in Montana is projected to rise about 29% by 2030 — from 3.2 in 2025 to a central estimate of 4.1 (95% range 0.38–7.8). A 5-year backtest shows a typical error of ±35.5%, with 100% of held-out values landing inside the 95% band.19682030
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 →
20264.10.457.8
20274.10.437.8
20284.10.417.8
20294.10.407.8
20304.10.387.8

Mallard Survey Routes in Montana

Routes recording Mallard in Montana.
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 →
Winnett6720252021
Ingomar3020251968
Oswego2820241978
St Xavier2520101979
Heart Butte2520192016
Chinook1420252016
Ester Lake1320252015
Jordan1120241968
Hebgen Lake1120252017
Winifred1020232023
Great Falls920251972
Reed Point920241981
Saco920252015
Westby820252015
Lambert820252022
Wise River720221993
Dinosaurs H.M.720252018
Virgelle620251979
Two Dot620251980
Shawmut620251979
Noxon620212000
East Glacier Park620242015
Philipsburg620242015
Roundup620252016
Cleveland520241979

Mallard Population Trend in Other States

alabamaalaskaarizonaarkansascaliforniacoloradoconnecticutdelawarefloridageorgiaidahoillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourinebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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