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

Western Grebe Population Trend in Wyoming

All statesWetland birds

Western Grebe in Wyoming has increased: up 43% on the route-weighted index since 1989.

+43%Since 1989TrendPercent 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 →
27Routes 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 →
37YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Western Grebe Trends in WyomingNotable 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 Western Grebe in Wyoming. See the full index history below.

Western Grebe Population Forecast in Wyoming

If the recent trend holds, Western Grebe in Wyoming is projected to rise about 21% by 2029 — from 0.25 in 2024 to a central estimate of 0.30 (95% range 0.00–0.62). A 5-year backtest shows a typical error of ±33.7%, with 100% of held-out values landing inside the 95% band.

+21%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 →
0.30Projected 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 →
0.00–0.6295% 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 →
±33.7%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, Western Grebe in Wyoming is projected to rise about 21% by 2029 — from 0.25 in 2024 to a central estimate of 0.30 (95% range 0.00–0.62). A 5-year backtest shows a typical error of ±33.7%, with 100% of held-out values landing inside the 95% band.19872029
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 →
20250.290.000.61
20260.290.000.61
20270.290.000.62
20280.300.000.62
20290.300.000.62

Western Grebe Survey Routes in Wyoming

Routes recording Western Grebe in Wyoming.
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 →
Carter 21920242018
Dwyer920161992
Midvale819961990
Tensleep619971997
Brookhurst420151991
Ethete420231998
Dayton320111988
Rawlins 2320222016
Rock River320221994
Clark220012001
Alpine220221989
Mtn View220242002
Flamin Gorge220101988
Yellowstone120221991
Colter Bay119971997
Nowood119961996
Fontenelle120241989
Mammoth120051991
Moose120131989
Lovell120031990
Colter Bay 2120222021
Seedskadee120021997
Fiddler Lk120141987
Moran120092003
Walcott120151995

Western Grebe Population Trend in Other States

arizonacaliforniacoloradoidahokansasminnesotamontananebraskanevadanew-mexiconorth-dakotaoregonsouth-dakotautahwashington

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