BirdAnalyst
Species · BCR 9 · BBS 2026 Release · 1966–2025

Green-winged Teal In Great Basin

All regionsGreat BasinWaterfowl

Green-winged Teal in Great Basin has surged: up 201% on the route-weighted index since 1971.

+201%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 →
99Routes 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 →
55YearsYears 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 →

Green-winged Teal has surged in Great Basin: up 201% on the route-weighted index since 1971.

Green-winged Teal In Great Basin Population Forecast

If the recent trend holds, Green-winged Teal in Great Basin is projected to fall about 48% by 2030 — from 0.35 in 2025 to a central estimate of 0.18 (95% range 0.00–0.52). A 5-year backtest shows a typical error of ±62.5%, with 100% of held-out values landing inside the 95% band.

-48%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 →
0.18Projected 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 →
0.00–0.5295% 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 →
±62.5%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, Green-winged Teal in Great Basin is projected to fall about 48% by 2030 — from 0.35 in 2025 to a central estimate of 0.18 (95% range 0.00–0.52). A 5-year backtest shows a typical error of ±62.5%, with 100% of held-out values landing inside the 95% band.19682030
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 →
20260.180.000.52
20270.180.000.52
20280.180.000.52
20290.180.000.52
20300.180.000.52

Routes In Great Basin

Routes recording Green-winged Teal 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 →
Fish LakeOREGON312025
CallaoUTAH302010
HarringtonWASHINGTON122000
Catlow RimOREGON102023
Dobbin CreekNEVADA82014
NighthawkWASHINGTON82019
Blizzard GapOREGON72004
Gardnerville 2NEVADA62025
WapatoWASHINGTON61990
SnowvilleUTAH52015
ZumwaltOREGON42004
TonasketWASHINGTON42013
Columbia NwrWASHINGTON42021
CedarvilleCALIFORNIA32025
Cedar HillIDAHO32022
Kyle CanyonIDAHO31998
JosephOREGON32023
Warner VallyOREGON32017
ChinchaloOREGON32025
Gold HillUTAH31999
Moses CouleeWASHINGTON31997
RavendaleCALIFORNIA22007
DorrisCALIFORNIA22017
MacdoelCALIFORNIA22011
Clear Lk ResCALIFORNIA22004

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