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

Blue-winged Teal Population Trend in Idaho

All statesWaterfowl

Blue-winged Teal in Idaho has declined: down 44% on the route-weighted index since 1971.

-44%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 →
24Routes 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 →
41YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Blue-winged Teal Trends in IdahoNotable 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 Idaho. See the full index history below.

Blue-winged Teal Population Forecast in Idaho

If the recent trend holds, Blue-winged Teal in Idaho is projected to fall about 100% by 2028 — from 0.06 in 2023 to a central estimate of 0.00 (95% range 0.00–0.33). A 5-year backtest shows a typical error of ±251.7%, with 80% of held-out values landing inside the 95% band.

-100%Change by 2028TrendPercent 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 →
0.00Projected 2028 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–0.3395% 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 →
±251.7%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 Idaho is projected to fall about 100% by 2028 — from 0.06 in 2023 to a central estimate of 0.00 (95% range 0.00–0.33). A 5-year backtest shows a typical error of ±251.7%, with 80% of held-out values landing inside the 95% band.19682028
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 →
20240.000.000.33
20250.000.000.33
20260.000.000.33
20270.000.000.33
20280.000.000.33

Blue-winged Teal Survey Routes in Idaho

Routes recording Blue-winged Teal in Idaho.
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 →
Mivoden719771977
Mud Lake520211989
Lolo Pass420041992
Iron Springs420211988
Cascade319751969
Leadore320121980
Glenns Ferry319681968
Naples220221972
Nezperce219961996
Dubois219771977
Blacks Creek219881971
Springfield220021972
Acequia219791979
Crane Creek219911991
Bates219941992
Cedar Hill220232002
Pasadena Val219921991
Blackft Res120101986
Baker119941974
Joel119961996
Picabo120052005
Preston119941990
Nezperce Nf119921992
Cabarton119921992

Blue-winged Teal Population Trend in Other States

alabamaalaskaarizonaarkansascaliforniacoloradodelawarefloridaillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanevadanew-hampshirenew-mexiconew-yorknorth-dakotaohiooklahomaoregonpennsylvaniarhode-islandsouth-dakotatennesseetexasutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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