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

Blue-winged Teal In Great Basin

All regionsGreat BasinWaterfowl

Blue-winged Teal in Great Basin has fallen sharply: down 59% on the route-weighted index since 1972.

-59%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 →
77Routes 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 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 →

Blue-winged Teal has fallen sharply in Great Basin: down 59% on the route-weighted index since 1972.

Blue-winged Teal In Great Basin Population Forecast

If the recent trend holds, Blue-winged Teal in Great Basin is projected to fall about 75% by 2029 — from 0.08 in 2024 to a central estimate of 0.02 (95% range 0.00–0.42). A 5-year backtest shows a typical error of ±176.2%, with 100% of held-out values landing inside the 95% band.

-75%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 →
0.02Projected 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 →
0.00–0.4295% 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 →
±176.2%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, Blue-winged Teal in Great Basin is projected to fall about 75% by 2029 — from 0.08 in 2024 to a central estimate of 0.02 (95% range 0.00–0.42). A 5-year backtest shows a typical error of ±176.2%, 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 →
20250.050.000.45
20260.040.000.44
20270.030.000.43
20280.030.000.43
20290.020.000.42

Routes In Great Basin

Routes recording Blue-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 →
Moses CouleeWASHINGTON92002
DorrisCALIFORNIA62019
HarwoodWASHINGTON61993
Honey LakeCALIFORNIA52024
Mud LakeIDAHO52021
EllensburgWASHINGTON51987
NighthawkWASHINGTON52019
Iron SpringsIDAHO42021
CallaoUTAH42024
BrewsterWASHINGTON42018
HarringtonWASHINGTON42000
BartleCALIFORNIA31984
LeadoreIDAHO32012
Glenns FerryIDAHO31968
Moses LakeWASHINGTON32010
AsotinWASHINGTON32002
TonasketWASHINGTON32014
EwanWASHINGTON31999
Columbia NwrWASHINGTON32021
BentonCALIFORNIA22023
LikelyCALIFORNIA21989
Davis CreekCALIFORNIA21980
MacdoelCALIFORNIA21999
Iron GateCALIFORNIA22015
DuboisIDAHO21977

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