BirdAnalyst
Species · BCR 19 · BBS 2025 Release · 1966–2024

Green-winged Teal In Central Mixed Grass Prairie

All regionsCentral Mixed Grass PrairieWaterfowl

Green-winged Teal in Central Mixed Grass Prairie has fallen sharply: down 61% on the route-weighted index since 1971.

-61%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 →
13Routes 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 →
35YearsYears 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 fallen sharply in Central Mixed Grass Prairie: down 61% on the route-weighted index since 1971.

Green-winged Teal In Central Mixed Grass Prairie Population Forecast

If the recent trend holds, Green-winged Teal in Central Mixed Grass Prairie is projected to stay roughly flat through 2029, near 0.01 (95% range 0.00–0.16). A 5-year backtest shows a typical error of ±76.8%, with 100% of held-out values landing inside the 95% band.

n/aChange 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 →
0.01Projected 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 →
0.00–0.1695% 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 →
±76.8%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 Central Mixed Grass Prairie is projected to stay roughly flat through 2029, near 0.01 (95% range 0.00–0.16). A 5-year backtest shows a typical error of ±76.8%, 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 →
20250.010.000.17
20260.010.000.16
20270.010.000.16
20280.010.000.16
20290.010.000.16

Routes In Central Mixed Grass Prairie

Routes recording Green-winged Teal in Central Mixed Grass Prairie.
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 →
AlbertKANSAS101987
St JohnKANSAS22017
StrattonNEBRASKA22015
GordonNEBRASKA22018
Crescent LkNEBRASKA22016
BrownleeNEBRASKA22002
MisslerKANSAS11980
HopewellKANSAS12009
Swan LakeNEBRASKA11997
Piester LakeNEBRASKA12017
KennedyNEBRASKA12024
TableNEBRASKA12016
Wheeler CoNEBRASKA12024

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