BirdAnalyst
Species · BCR 9 · BBS 2025 Release · 1966–2024

American Wigeon In Great Basin

All regionsGreat BasinWaterfowl

American Wigeon in Great Basin has surged: up 88% on the route-weighted index since 1972.

+88%Since 1972TrendPercent 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 →
79Routes In RegionSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
54YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable SignalsNotable 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 →

American Wigeon has surged in Great Basin: up 87% on the route-weighted index since 1972.

American Wigeon In Great Basin Population Forecast

If the recent trend holds, American Wigeon in Great Basin is projected to fall about 34% by 2029 — from 0.39 in 2024 to a central estimate of 0.25 (95% range 0.00–0.68). A 5-year backtest shows a typical error of ±104.9%, with 100% of held-out values landing inside the 95% band.

-34%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 →
0.25Projected 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 →
0.00–0.6895% 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 →
±104.9%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, American Wigeon in Great Basin is projected to fall about 34% by 2029 — from 0.39 in 2024 to a central estimate of 0.25 (95% range 0.00–0.68). A 5-year backtest shows a typical error of ±104.9%, 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 →
20250.260.000.68
20260.260.000.68
20270.260.000.68
20280.260.000.68
20290.250.000.68

Routes In Great Basin

Routes recording American Wigeon in Great Basin.
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 →
Catlow RimOREGON242024
Fish LakeOREGON202024
PrincetonOREGON151981
Chimney Res.NEVADA102017
Iron SpringsIDAHO82024
Clear Lk ResCALIFORNIA72001
Gold HillUTAH72015
RimrockWASHINGTON62023
CratersIDAHO51987
MerrillOREGON52005
MadelineCALIFORNIA42011
Iron GateCALIFORNIA41994
Blizzard GapOREGON41994
Warner VallyOREGON42023
LynnUTAH42013
Turnbull NwrWASHINGTON42013
DorrisCALIFORNIA32017
Crowder FlatCALIFORNIA32018
Green Mtn.OREGON31997
DeltaUTAH32005
Bear RiverUTAH32022
NubieberCALIFORNIA22003
IngallsCALIFORNIA22001
LikelyCALIFORNIA22014
MacdoelCALIFORNIA21993

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