BirdAnalyst
Species · BCR 2 · BBS 2025 Release · 1966–2024

Green-winged Teal In BCR 2

All regionsBCR 2Waterfowl

Green-winged Teal in BCR 2 has collapsed: down 80% on the route-weighted index since 1986.

-80%Since 1986TrendPercent 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 →
22Routes 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 →
39YearsYears 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 →

Green-winged Teal has collapsed in BCR 2: down 80% on the route-weighted index since 1986.

Forecast

If the recent trend holds, Green-winged Teal in BCR 2 is projected to fall about 67% by 2029 — from 1.7 in 2024 to a central estimate of 0.55 (95% range 0.00–3.2). A 5-year backtest shows a typical error of ±26%, with 100% of held-out values landing inside the 95% band.

-67%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 →
0.55Projected 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 →
0.00–3.295% 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 →
±26%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 BCR 2 is projected to fall about 67% by 2029 — from 1.7 in 2024 to a central estimate of 0.55 (95% range 0.00–3.2). A 5-year backtest shows a typical error of ±26%, with 100% of held-out values landing inside the 95% band.19832029
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 →
20250.750.003.4
20260.700.003.3
20270.650.003.3
20280.600.003.2
20290.550.003.2

Routes In BCR 2

Routes recording Green-winged Teal in BCR 2.
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 →
KotzebueALASKA112024
Kotzebue (Short)ALASKA91994
KodiakALASKA61983
Gweek RiverALASKA62002
Kanektok RivALASKA42003
Cape NomeALASKA32019
Goodnews BayALASKA32005
Cold Bay (Short)ALASKA31992
ChiniakALASKA22021
DillinghamALASKA21999
Kodiak 2ALASKA22019
Salmon LakeALASKA22019
TellerALASKA22024
Togiak RiverALASKA22004
TupuknukALASKA21995
Katmai N.P.ALASKA11995
Cold BayALASKA12024
King SalmonALASKA12024
CouncilALASKA12019
NomeALASKA12022
St. Mary'SALASKA11999
Selawik (Short)ALASKA11987

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