BirdAnalyst
Species · South Dakota · BBS 2025 Release · 1966–2024

Mallard Population Trend in South Dakota

All statesWaterfowl

Mallard in South Dakota has held roughly steady: down 9% on the route-weighted index since 1969.

-9%Since 1969TrendPercent 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 →
64Routes 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 South DakotaNotable 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 South Dakota. See the full index history below.

Mallard Population Forecast in South Dakota

If the recent trend holds, Mallard in South Dakota is projected to rise about 71% by 2029 — from 8.0 in 2024 to a central estimate of 14 (95% range 3.2–24). A 5-year backtest shows a typical error of ±48.5%, with 100% of held-out values landing inside the 95% band.

+71%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 →
14Projected 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 →
3.2–2495% 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 →
±48.5%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 South Dakota is projected to rise about 71% by 2029 — from 8.0 in 2024 to a central estimate of 14 (95% range 3.2–24). A 5-year backtest shows a typical error of ±48.5%, with 100% of held-out values landing inside the 95% band.19672029
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 →
2025143.024
2026143.024
2027143.124
2028143.224
2029143.224

Mallard Survey Routes in South Dakota

Routes recording Mallard in South Dakota.
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 →
Conde19619841967
Gettysburg13720231969
Raymond8620211967
Promise5320151971
Isabel4520151990
Volga4420241967
Eagle Butte4220151990
Wilmot4120241967
Long Lake3620191967
White Lake3420111967
Roswell3220141967
Gorman3020101979
S. Pioneer2020231994
Britton1920231967
Forbes1820241967
Cottonwood1620241992
Veblen1520231967
Howard1420241970
Lodgepole1320241995
Chamberlain1120111967
Volunteer1120191967
Lane919991967
Laplant920151971
Norbeck820021995
Lane 2820142000

Mallard Population Trend in Other States

alabamaalaskaarizonaarkansascaliforniacoloradoconnecticutdelawarefloridageorgiaidahoillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniarhode-islandsouth-carolinatennesseetexasutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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