BirdAnalyst
Species · New Hampshire · BBS 2026 Release · 1966–2025

Mallard Population Trend in New Hampshire

All statesWaterfowl

Mallard in New Hampshire has surged: up 192% on the route-weighted index since 1968.

+192%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 →
26Routes 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 New HampshireNotable signalsLong-arc shifts the engine flags automatically — sustained declines or increases large enough to stand out from year-to-year noise.Full methodology →

long arc increasecomputed indexTrend sourceWhether the figure is our own computed route-weighted index or an official USGS modeled estimate. The current build labels every trend as computed.Full methodology →

Mallard has surged in New Hampshire: up 192% on the route-weighted index since 1968.

Mallard Population Forecast in New Hampshire

If the recent trend holds, Mallard in New Hampshire is projected to rise about 24% by 2030 — from 1.6 in 2025 to a central estimate of 1.9 (95% range 0.84–3.0). A 5-year backtest shows a typical error of ±14.7%, with 100% of held-out values landing inside the 95% band.

+24%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 →
1.9Projected 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 →
0.84–3.095% 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 →
±14.7%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 New Hampshire is projected to rise about 24% by 2030 — from 1.6 in 2025 to a central estimate of 1.9 (95% range 0.84–3.0). A 5-year backtest shows a typical error of ±14.7%, 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 →
20261.80.743.0
20271.90.763.0
20281.90.793.0
20291.90.813.0
20301.90.843.0

Mallard Survey Routes in New Hampshire

Routes recording Mallard in New Hampshire.
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 →
Epsom1020251980
Dover820241980
Gilmantn I W620251990
Franconia620251986
Peterborough519991984
Crawford Not519741967
Walpole420251994
Marlow420131990
East Kingston420251999
Concord320151966
Wilmot320131991
Brentwood219971997
Fitzwilliam220241970
Hopkinton220251980
Jefferson Hl220191992
Dixville Notch 2220182018
Strafford120251980
Canterbury120251978
Mt Chocorua120251973
Lempster120231975
Milan120241978
Stratford120241978
Dixvil Notch120091988
Clarksville120231977
Glen120221991

Mallard Population Trend in Other States

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

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