BirdAnalyst
Species · South Dakota · BBS 2026 Release · 1966–2025

Mallard Population Trend in South Dakota

All statesWaterfowl

Mallard in South Dakota has edged down: down 19% on the route-weighted index since 1969.

-19%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 →
58YearsYears 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 166% by 2030 — from 4.9 in 2025 to a central estimate of 13 (95% range 2.5–24). A 5-year backtest shows a typical error of ±87.5%, with 100% of held-out values landing inside the 95% band.

+166%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 →
13Projected 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 →
2.5–2495% 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 →
±87.5%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 166% by 2030 — from 4.9 in 2025 to a central estimate of 13 (95% range 2.5–24). A 5-year backtest shows a typical error of ±87.5%, with 100% of held-out values landing inside the 95% band.19672030
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 →
2026132.324
2027132.324
2028132.424
2029132.424
2030132.524

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
Eagle Butte4220151990
Long Lake3620191967
White Lake3420111967
Roswell3220141967
Volga3120251967
Gorman3020101979
S. Pioneer2020231994
Wilmot1920251967
Britton1920231967
Tripp1620251971
Veblen1520231967
Howard1420251970
Cottonwood1420251992
Chamberlain1120111967
Volunteer1120191967
Forbes1020251967
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 2026-08-14.