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

Mallard Population Trend in Maryland

All statesWaterfowl

Mallard in Maryland has held roughly steady: down 6% on the route-weighted index since 1968.

-6%Since 1968TrendPercent 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 →
74Routes 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 →
59YearsYears 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 MarylandNotable 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 Maryland. See the full index history below.

Mallard Population Forecast in Maryland

If the recent trend holds, Mallard in Maryland is projected to rise about 271% by 2030 — from 0.71 in 2025 to a central estimate of 2.6 (95% range 0.00–6.1). A 5-year backtest shows a typical error of ±322.5%, with 100% of held-out values landing inside the 95% band.

+271%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 →
2.6Projected 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 →
0.00–6.195% 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 →
±322.5%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 Maryland is projected to rise about 271% by 2030 — from 0.71 in 2025 to a central estimate of 2.6 (95% range 0.00–6.1). A 5-year backtest shows a typical error of ±322.5%, with 100% of held-out values landing inside the 95% band.19662030
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 →
20262.60.006.0
20272.60.006.1
20282.60.006.1
20292.60.006.1
20302.60.006.1

Mallard Survey Routes in Maryland

Routes recording Mallard in Maryland.
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 →
Smithsburg1320141970
Fair Hill1319961992
Williamsport1020251968
Oldtown919781978
Beltsville920121973
La Plata720091968
St. George'S Island620172015
Island Creek620241992
Mt Nebo519911978
Vindex520081967
Broomes Isl519961969
Randallstown419981973
Van Bibber420061973
Northeast420161969
Millington420251970
Madison420241966
Newark420181971
Berlin420161984
Upper Xrds320081969
Jones319941966
Pt Republic319741974
Harmony320171977
Easton320211971
Golden Hill320251971
Mardela320151968

Mallard Population Trend in Other States

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

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