Species · Alaska · BBS 2025 Release · 1966–2024

Harlequin Duck Population Trend in Alaska

Harlequin Duck in Alaska has collapsed: down 76% on the route-weighted index since 1983.

-76%Since 1983
38Routes In State
43Years

Notable Harlequin Duck Trends in Alaska

long arc declinecomputed index

Harlequin Duck has collapsed in Alaska: down 76% on the route-weighted index since 1983.

Harlequin Duck Population Forecast in Alaska

If the recent trend holds, Harlequin Duck in Alaska is projected to fall about 100% by 2029 — from 0.22 in 2024 to a central estimate of 0.00 (95% range 0.00–1.6). A 5-year backtest shows a typical error of ±135.9%, with 100% of held-out values landing inside the 95% band.

-100%Change by 2029
0.00Projected 2029 index
0.001.695% range
±135.9%Backtest error
19752029
Projection of the recent trend (dashed) with 80/95% bands — a projection, not a prediction. Habitat, climate, and land use are not modeled.
YearProjected index95% low95% high
20250.000.001.6
20260.000.001.6
20270.000.001.6
20280.000.001.6
20290.000.001.6

Harlequin Duck Survey Routes in Alaska

Routes recording Harlequin Duck in Alaska.
Zarembo4720012001
Thorne Bay1819941993
Adak1620011983
Mitkof Isle1619951988
Sourdough1419941994
Chiniak1220231985
Skagway820241993
Thorne Bay 2820232023
Zimovia Strt720241988
Unalakleet River620231996
Cape Nome520181993
Salmon Lake520181994
Teller520181995
Sitka (Short)519921984
Juneau420231993
Petersburg419871987
Juneau Alt319851984
Stikine River220072007
Council220181994
Haines220221975
Nome220121999
Hyder220072003
Kotzebue220192019
Kodiak 2220211985
Savage220071994

Harlequin Duck Population Trend in Other States

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