BirdAnalyst
Species · BCR 10 · BBS 2025 Release · 1966–2024

Blue-winged Teal In Northern Rockies

All regionsNorthern RockiesWaterfowl

Blue-winged Teal in Northern Rockies has declined: down 42% on the route-weighted index since 1970.

-42%Since 1970TrendPercent 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 →
82Routes 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 →
56YearsYears 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 →

No notable trend signals for Blue-winged Teal in Northern Rockies. See the full index history below.

Blue-winged Teal In Northern Rockies Population Forecast

If the recent trend holds, Blue-winged Teal in Northern Rockies is projected to fall about 53% by 2029 — from 0.10 in 2024 to a central estimate of 0.05 (95% range 0.00–0.47). A 5-year backtest shows a typical error of ±53.8%, with 100% of held-out values landing inside the 95% band.

-53%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 →
0.05Projected 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 →
0.00–0.4795% 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 →
±53.8%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 Northern Rockies is projected to fall about 53% by 2029 — from 0.10 in 2024 to a central estimate of 0.05 (95% range 0.00–0.47). A 5-year backtest shows a typical error of ±53.8%, 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 →
20250.070.000.49
20260.060.000.49
20270.060.000.48
20280.050.000.48
20290.050.000.47

Routes In Northern Rockies

Routes recording Blue-winged Teal in Northern Rockies.
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 →
ArmintoWYOMING132004
MivodenIDAHO71977
AugustaMONTANA72021
AnchorWYOMING62016
ShirleyWYOMING61998
Pablo Res.MONTANA52023
Clover CreekOREGON51977
Saleratus CrUTAH52007
CurlewWASHINGTON51993
NowoodWYOMING52024
Lolo PassIDAHO42004
PolsonMONTANA41999
East Glacier ParkMONTANA42021
Green RiverWYOMING41978
CascadeIDAHO31975
Wise RiverMONTANA32018
Willow Creek 2MONTANA32001
SpartaOREGON31977
OttoWYOMING32005
RiversideWYOMING31997
Crazy WomanWYOMING32006
BoulderWYOMING32022
Rock RiverWYOMING31998
MaybellCOLORADO21982
LayCOLORADO22000

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