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Species · Wyoming · BBS 2025 Release · 1966–2024

Pied-billed Grebe Population Trend in Wyoming

All statesWetland birds

Pied-billed Grebe in Wyoming has collapsed: down 85% on the route-weighted index since 1973.

-85%Since 1973TrendPercent 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 →
35Routes 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 →
50YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Pied-billed 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 →

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 →

Pied-billed Grebe has collapsed in Wyoming: down 85% on the route-weighted index since 1973.

Pied-billed Grebe Population Forecast in Wyoming

If the recent trend holds, Pied-billed Grebe in Wyoming is projected to stay roughly flat through 2029, near 0.04 (95% range 0.00–0.21). A 5-year backtest shows a typical error of ±57.7%, 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 →
0.04Projected 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 →
0.00–0.2195% 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 →
±57.7%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, Pied-billed Grebe in Wyoming is projected to stay roughly flat through 2029, near 0.04 (95% range 0.00–0.21). A 5-year backtest shows a typical error of ±57.7%, with 100% of held-out values landing inside the 95% band.19712029
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 →
20250.040.000.22
20260.040.000.22
20270.040.000.21
20280.040.000.21
20290.040.000.21

Pied-billed Grebe Survey Routes in Wyoming

Routes recording Pied-billed 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 →
Rawlins 21220162015
Brookhurst320191971
Tensleep320152015
Kaycee320242022
Wyarno219871975
Natrona219871974
Recluse220161992
Lamont219991987
Green River219821978
Ne Entrance120011992
Clarkelen119781972
Yellowstone120012001
Midvale120002000
Seely 2120142014
Mckinnon119801978
Patrick Draw119801980
Mammoth120151988
Hunter Peak120031983
Clark120032003
Carter 2120242021
Lovell120051993
Dayton119931981
Seely120001994
Crowheart120212008
Teapot Dome119831983

Pied-billed Grebe Population Trend in Other States

alabamaalaskaarizonaarkansascaliforniacoloradoconnecticutdelawarefloridageorgiaidahoillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniasouth-carolinasouth-dakotatennesseetexasutahvermontvirginiawashingtonwisconsin

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