Species · Oregon · BBS 2025 Release · 1966–2024

American Bittern Population Trend in Oregon

American Bittern in Oregon has fallen sharply: down 61% on the route-weighted index since 1973.

-61%Since 1973
22Routes In State
47Years

Notable American Bittern Trends in Oregon

long arc declinecomputed index

American Bittern has fallen sharply in Oregon: down 61% on the route-weighted index since 1973.

American Bittern Population Forecast in Oregon

If the recent trend holds, American Bittern in Oregon is projected to stay roughly flat through 2029, near 0.00 (95% range 0.00–0.24). A 5-year backtest shows a typical error of ±76.3%, with 100% of held-out values landing inside the 95% band.

n/aChange by 2029
0.00Projected 2029 index
0.000.2495% range
±76.3%Backtest error
19702029
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
20250.020.000.25
20260.010.000.25
20270.010.000.24
20280.010.000.24
20290.000.000.24

American Bittern Survey Routes in Oregon

Routes recording American Bittern in Oregon.
Merrill420131998
Warner Vally419991996
Bly220012001
Tualatin119941994
Nicolai Mtn.119971997
Days Creek120112011
Modoc Point119841970
Alvord Lake119721972
Bly 2120212007
Adair120121997
Dayton119931993
Elk Lake120241976
Silver Creek120182018
Princeton119841975
Fish Lake120241972
Coquille120232023
Harney Lake120021999
Catlow Rim120152015
Crooked Riv.120022002
Sheaville120222012
Chinchalo120221996
Sams Valley119941994

American Bittern Population Trend in Other States

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