BirdAnalyst
Species · Oregon · BBS 2026 Release · 1966–2025

Lesser Scaup Population Trend in Oregon

All statesWaterfowl

Lesser Scaup in Oregon has surged: up 249% on the route-weighted index since 1971.

+249%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 →
21Routes 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 →
46YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Lesser Scaup 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 increasecomputed 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 →

Lesser Scaup has surged in Oregon: up 248% on the route-weighted index since 1971.

Lesser Scaup Population Forecast in Oregon

If the recent trend holds, Lesser Scaup in Oregon is projected to rise about 14% by 2030 — from 0.20 in 2025 to a central estimate of 0.23 (95% range 0.00–0.77). A 5-year backtest shows a typical error of ±414.2%, with 100% of held-out values landing inside the 95% band.

+14%Change by 2030TrendPercent 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 →
0.23Projected 2030 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–0.7795% 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 →
±414.2%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, Lesser Scaup in Oregon is projected to rise about 14% by 2030 — from 0.20 in 2025 to a central estimate of 0.23 (95% range 0.00–0.77). A 5-year backtest shows a typical error of ±414.2%, with 100% of held-out values landing inside the 95% band.19692030
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 →
20260.230.000.77
20270.230.000.77
20280.230.000.77
20290.230.000.77
20300.230.000.77

Lesser Scaup Survey Routes in Oregon

Routes recording Lesser Scaup 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 →
Blizzard Gap1020171995
Modoc Point 2820252025
Princeton719751972
Catlow Rim720251994
Clover Creek619971997
Modoc Point520091974
Fish Lake520251974
Lapham Res.219981994
Dell Spring219721970
Wedderburn219941994
Bly 2220152015
Joseph219941994
Barnes Val219741974
Donnelly220062005
Chinchalo219991993
Winberry119691969
Elk Lake119781978
Warner Vally120241994
Umatilla119921992
Sheaville120142014
Trout Creek119981998

Lesser Scaup Population Trend in Other States

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Source: USGS North American Breeding Bird Survey, retrieved 2026-08-14.