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

Lesser Scaup Population Trend in Wyoming

All statesWaterfowl

Lesser Scaup in Wyoming has surged: up 121% on the route-weighted index since 1977.

+121%Since 1977TrendPercent 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 →
38Routes 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 →
47YearsYears 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 WyomingNotable 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 Wyoming: up 121% on the route-weighted index since 1977.

Lesser Scaup Population Forecast in Wyoming

If the recent trend holds, Lesser Scaup in Wyoming is projected to rise about 354% by 2029 — from 0.23 in 2024 to a central estimate of 1.0 (95% range 0.00–2.6). A 5-year backtest shows a typical error of ±405.6%, with 100% of held-out values landing inside the 95% band.

+354%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 →
1.0Projected 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 →
0.00–2.695% 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 →
±405.6%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 Wyoming is projected to rise about 354% by 2029 — from 0.23 in 2024 to a central estimate of 1.0 (95% range 0.00–2.6). A 5-year backtest shows a typical error of ±405.6%, with 100% of held-out values landing inside the 95% band.19682029
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 →
20251.00.002.6
20261.00.002.6
20271.00.002.6
20281.00.002.6
20291.00.002.6

Lesser Scaup Survey Routes in Wyoming

Routes recording Lesser Scaup in Wyoming.
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 →
Hayden Val2919861985
Mammoth1320241982
Clark1220012000
Yellowstone1120221987
Rock River820221990
Bucknum520011993
Hunter Peak420241996
Seedskadee419971997
Warbonnet420172002
Fontenelle319871987
Ervay320182018
Crazy Woman320101998
Fiddler Lk320111982
Dubois220112011
Brookhurst219921968
Cumberland219991977
Moose220191977
Boulder220222016
Pathfinder220011995
Harmony220212014
Welch219911991
Ne Entrance120211982
Cody119981998
Colter Bay119701970
Nowood120241993

Lesser Scaup Population Trend in Other States

alaskacaliforniacoloradoidahoiowakansasmichiganminnesotamontananebraskanevadanew-mexiconorth-dakotaoregonsouth-dakotautahwashingtonwisconsin

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