BirdAnalyst
Species · BCR 4 · BBS 2025 Release · 1966–2024

Green-winged Teal In BCR 4

All regionsBCR 4Waterfowl

Green-winged Teal in BCR 4 has surged: up 100% on the route-weighted index since 1984.

+100%Since 1984TrendPercent 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 →
47Routes 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 →
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 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 BCR 4: up 100% on the route-weighted index since 1984.

Green-winged Teal In BCR 4 Population Forecast

If the recent trend holds, Green-winged Teal in BCR 4 is projected to fall about 48% by 2029 — from 2.2 in 2024 to a central estimate of 1.1 (95% range 0.03–2.2). A 5-year backtest shows a typical error of ±173.8%, with 100% of held-out values landing inside the 95% band.

-48%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 →
1.1Projected 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 →
0.03–2.295% 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 →
±173.8%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, Green-winged Teal in BCR 4 is projected to fall about 48% by 2029 — from 2.2 in 2024 to a central estimate of 1.1 (95% range 0.03–2.2). A 5-year backtest shows a typical error of ±173.8%, with 100% of held-out values landing inside the 95% band.19822029
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 →
20251.10.002.2
20261.10.002.2
20271.10.012.2
20281.10.022.2
20291.10.032.2

Routes In BCR 4

Routes recording Green-winged Teal in BCR 4.
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 →
SlanaALASKA192024
Hather CreekALASKA122024
Mud RiverALASKA112024
Unalakleet RiverALASKA82024
Kanuti CanynALASKA62024
Anvik RiverALASKA52024
Kanuti LakeALASKA52024
Bear CreekALASKA41990
Chena Hot Spring 2ALASKA42021
Pinoche Tral (Short)ALASKA41984
MaclarenALASKA32024
KalifonskyALASKA32016
ChickenALASKA32024
Paxson LakeALASKA31996
Mccarthy Rd2ALASKA31999
ChistochinaALASKA22023
L SalchaALASKA22002
Chena Hot SpALASKA21987
SourdoughALASKA22000
Hatcher PassALASKA22012
WasillaALASKA21983
PetersvilleALASKA22003
KachemakALASKA21998
Burma RoadALASKA22001
Donelly DomeALASKA22019

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