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

Bufflehead Population Trend in Oregon

All statesWaterfowl

Bufflehead in Oregon has collapsed: down 82% on the route-weighted index since 1971.

-82%Since 1971TrendPercent 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 →
14Routes 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 →
40YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Bufflehead Trends in OregonNotable 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 →

Bufflehead has collapsed in Oregon: down 82% on the route-weighted index since 1971.

Bufflehead Population Forecast in Oregon

If the recent trend holds, Bufflehead in Oregon is projected to fall about 54% by 2029 — from 0.12 in 2024 to a central estimate of 0.05 (95% range 0.00–0.44). A 5-year backtest shows a typical error of ±88.3%, with 100% of held-out values landing inside the 95% band.

-54%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 →
0.05Projected 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 →
0.00–0.4495% 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 →
±88.3%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, Bufflehead in Oregon is projected to fall about 54% by 2029 — from 0.12 in 2024 to a central estimate of 0.05 (95% range 0.00–0.44). A 5-year backtest shows a typical error of ±88.3%, with 100% of held-out values landing inside the 95% band.19692029
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 →
20250.060.000.45
20260.060.000.45
20270.060.000.45
20280.060.000.44
20290.050.000.44

Bufflehead Survey Routes in Oregon

Routes recording Bufflehead in Oregon.
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 →
Modoc Point1820001973
Catlow Rim820242017
Deschutes720222022
Barnes Val419871974
Elk Lake319861975
Bly 2220192014
Merrill120122012
Warner Vally120241994
Summit Pr120232023
Lapham Res.120241993
Dell Spring119901969
Newbridge120242024
Wedderburn119941994
Blizzard Gap120222003

Bufflehead Population Trend in Other States

alaskacaliforniacoloradoidahominnesotamontananevadanorth-dakotasouth-dakotautahwashingtonwisconsinwyoming

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