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

Mallard Population Trend in South Carolina

All statesWaterfowl

Mallard in South Carolina has declined: down 31% on the route-weighted index since 1979.

-31%Since 1979TrendPercent 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 →
19Routes 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 →
30YearsYears 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 CarolinaNotable 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 Carolina. See the full index history below.

Mallard Population Forecast in South Carolina

If the recent trend holds, Mallard in South Carolina is projected to fall about 67% by 2029 — from 0.38 in 2024 to a central estimate of 0.13 (95% range 0.00–0.46). A 5-year backtest shows a typical error of ±62.6%, with 100% of held-out values landing inside the 95% band.

-67%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 →
0.13Projected 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 →
0.00–0.4695% 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 →
±62.6%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, Mallard in South Carolina is projected to fall about 67% by 2029 — from 0.38 in 2024 to a central estimate of 0.13 (95% range 0.00–0.46). A 5-year backtest shows a typical error of ±62.6%, with 100% of held-out values landing inside the 95% band.19772029
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 →
20250.140.000.47
20260.140.000.47
20270.130.000.47
20280.130.000.46
20290.130.000.46

Mallard Survey Routes in South Carolina

Routes recording Mallard in South Carolina.
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 →
Prosperity820241998
Wagener620181978
Campobello620232021
Owings 2520102010
Walterboro320062006
Holly Hill220092008
Little Mtn219861977
Landrum219881988
Salem220142010
Bennettsville220082000
Pinewood220092009
Adams Run220102010
Anderson220032003
Bishopville120182018
Barton Creek120111983
Plum Branch120161979
Blacksburg120132003
Joanna120042004
Cauthens Xrd120092009

Mallard Population Trend in Other States

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

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