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

Mallard Population Trend in Montana

All statesWaterfowl

Mallard in Montana has edged down: down 19% on the route-weighted index since 1970.

-19%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 →
105Routes 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 →
56YearsYears 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 26% by 2029 — from 3.3 in 2024 to a central estimate of 4.2 (95% range 0.47–7.9). A 5-year backtest shows a typical error of ±26.7%, with 100% of held-out values landing inside the 95% band.

+26%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 →
4.2Projected 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 →
0.47–7.995% 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 →
±26.7%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, Mallard in Montana is projected to rise about 26% by 2029 — from 3.3 in 2024 to a central estimate of 4.2 (95% range 0.47–7.9). A 5-year backtest shows a typical error of ±26.7%, 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 →
20254.20.538.0
20264.20.518.0
20274.20.507.9
20284.20.487.9
20294.20.477.9

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 →
Great Falls3120241972
Oswego2820241978
St Xavier2520101979
Heart Butte2520192016
Ester Lake2420242015
Hay Lake2020221989
Saco1920232015
Pablo Res.1720241995
Chinook1720242016
Westby1720242015
Webster1620241978
Hebgen Lake1620242017
Jordan1120241968
Shawmut1120241979
Winifred1020232023
Reed Point920241981
Locate820241986
Elliston720231970
Ingomar720231968
Wise River720221993
Brandenberg620141968
Noxon620212000
East Glacier Park620242015
Philipsburg620242015
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 2026-05-22.