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

Mallard Population Trend in Connecticut

All statesWaterfowl

Mallard in Connecticut has fallen sharply: down 73% on the route-weighted index since 1968.

-73%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 →
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 →
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 ConnecticutNotable 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 declinecomputed 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 fallen sharply in Connecticut: down 73% on the route-weighted index since 1968.

Mallard Population Forecast in Connecticut

If the recent trend holds, Mallard in Connecticut is projected to rise about 281% by 2030 — from 0.38 in 2025 to a central estimate of 1.4 (95% range 0.00–4.3). A 5-year backtest shows a typical error of ±569.2%, with 100% of held-out values landing inside the 95% band.

+281%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 →
1.4Projected 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 →
0.00–4.395% 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 →
±569.2%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 Connecticut is projected to rise about 281% by 2030 — from 0.38 in 2025 to a central estimate of 1.4 (95% range 0.00–4.3). A 5-year backtest shows a typical error of ±569.2%, 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 →
20261.50.004.4
20271.50.004.4
20281.50.004.3
20291.50.004.3
20301.40.004.3

Mallard Survey Routes in Connecticut

Routes recording Mallard in Connecticut.
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 →
Buckingham2220221966
New Hartford720211994
Sherman520181980
Danbury420221971
Southington420241973
No Woodbury320111967
E Hartland219921971
Woodstock219961970
Westbrook220251974
Woodstock 2220172017
Mystic120231973
Uncasville120191989
Willimantic120171974
Greenwich120071968
Warren120111973
Long Hill120191972
Mid Haddam120241973
New Hartford119871973
Granby120251988

Mallard Population Trend in Other States

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

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