BirdAnalyst
Species · Maine · BBS 2025 Release · 1966–2024

American Black Duck Population Trend in Maine

All statesWaterfowl

American Black Duck in Maine has collapsed: down 88% on the route-weighted index since 1968.

-88%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 →
56Routes 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 →
54YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable American Black Duck Trends in MaineNotable 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 →

American Black Duck has collapsed in Maine: down 88% on the route-weighted index since 1968.

American Black Duck Population Forecast in Maine

If the recent trend holds, American Black Duck in Maine is projected to fall about 58% by 2029 — from 0.21 in 2024 to a central estimate of 0.09 (95% range 0.00–0.80). A 5-year backtest shows a typical error of ±357.2%, with 100% of held-out values landing inside the 95% band.

-58%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 →
0.09Projected 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 →
0.00–0.8095% 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 →
±357.2%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, American Black Duck in Maine is projected to fall about 58% by 2029 — from 0.21 in 2024 to a central estimate of 0.09 (95% range 0.00–0.80). A 5-year backtest shows a typical error of ±357.2%, with 100% of held-out values landing inside the 95% band.19662029
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 →
20250.130.000.85
20260.120.000.83
20270.110.000.82
20280.100.000.81
20290.090.000.80

American Black Duck Survey Routes in Maine

Routes recording American Black Duck in Maine.
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 →
Warren719891986
Harmony720151968
Hancock719981979
Horse Mtn520101984
Biddeford420001975
Manchester419951976
Carrabassett420001983
Benedicta419931993
Washburn419961987
Newcastle319941981
Otisfield Gr320111972
Hermon320112011
Seboomook Lk320141974
Medway320021976
Wilson Mills220241991
Reeds220241997
South Arm220121975
Bowdoin Ctr220031986
Brooks220061986
Deblois220071975
Northfield219761976
Carrying Pl220131980
Baxter219841984
Boundary219971993
Lake Moxie220162014

American Black Duck Population Trend in Other States

alabamaconnecticutdelawareindianamarylandmassachusettsmichiganminnesotanew-hampshirenew-jerseynew-yorknorth-carolinanorth-dakotaohiopennsylvaniarhode-islandvermontvirginiawest-virginiawisconsin

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