BirdAnalyst
Species · BCR 13 · BBS 2025 Release · 1966–2024

American Black Duck In Lower Great Lakes / St. Lawrence Plain

All regionsLower Great Lakes / St. Lawrence PlainWaterfowl

American Black Duck in Lower Great Lakes / St. Lawrence Plain has collapsed: down 92% on the route-weighted index since 1968.

-92%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 →
42Routes In RegionSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
38YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable SignalsNotable 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 Lower Great Lakes / St. Lawrence Plain: down 92% on the route-weighted index since 1968.

Forecast

If the recent trend holds, American Black Duck in Lower Great Lakes / St. Lawrence Plain is projected to stay roughly flat through 2021, near 0.00 (95% range 0.00–0.20). A 5-year backtest shows a typical error of ±312.3%, with 100% of held-out values landing inside the 95% band.

n/aChange by 2021TrendPercent 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 →
0.00Projected 2021 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–0.2095% 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 →
±312.3%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 Lower Great Lakes / St. Lawrence Plain is projected to stay roughly flat through 2021, near 0.00 (95% range 0.00–0.20). A 5-year backtest shows a typical error of ±312.3%, with 100% of held-out values landing inside the 95% band.19662021
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 →
20170.000.000.20
20180.000.000.20
20190.000.000.20
20200.000.000.20
20210.000.000.20

Routes In Lower Great Lakes / St. Lawrence Plain

Routes recording American Black Duck in Lower Great Lakes / St. Lawrence Plain.
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 →
BranchportNEW-YORK141970
West BangorNEW-YORK101998
Ballston LkNEW-YORK91983
FowlerNEW-YORK51968
SalemNEW-YORK41982
GhentNEW-YORK31973
N WilmurtNEW-YORK31997
CloverPENNSYLVANIA31995
HighlandNEW-YORK22006
Oriskany FlsNEW-YORK21968
MacdougallNEW-YORK21977
HamburgNEW-YORK21973
West SenecaNEW-YORK21972
SheridanNEW-YORK21975
PulaskiNEW-YORK21974
North EastonNEW-YORK21991
WillsboroNEW-YORK21976
Ferris CrnrsPENNSYLVANIA22016
North PownalVERMONT21975
RhinebeckNEW-YORK11996
W ShokanNEW-YORK11991
AusterlitzNEW-YORK11999
CatskillsNEW-YORK11969
DuanesburgNEW-YORK11984
RushvilleNEW-YORK11973

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