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Species · Nevada · BBS 2025 Release · 1966–2024

Western Grebe Population Trend in Nevada

All statesWetland birds

Western Grebe in Nevada has collapsed: down 93% on the route-weighted index since 1994.

-93%Since 1994TrendPercent 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 →
7Routes 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 →
18YearsYears 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 NevadaNotable 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 →

Western Grebe has collapsed in Nevada: down 93% on the route-weighted index since 1994.

Western Grebe Population Forecast in Nevada

If the recent trend holds, Western Grebe in Nevada is projected to fall about 100% by 2027 — from 0.07 in 2022 to a central estimate of 0.00 (95% range 0.00–0.97). A 5-year backtest shows a typical error of ±558.2%, with 100% of held-out values landing inside the 95% band.

-100%Change by 2027TrendPercent 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 →
0.00Projected 2027 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–0.9795% 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 →
±558.2%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 Nevada is projected to fall about 100% by 2027 — from 0.07 in 2022 to a central estimate of 0.00 (95% range 0.00–0.97). A 5-year backtest shows a typical error of ±558.2%, with 100% of held-out values landing inside the 95% band.19882027
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 →
20230.000.000.97
20240.000.000.97
20250.000.000.97
20260.000.000.97
20270.000.000.97

Western Grebe Survey Routes in Nevada

Routes recording Western Grebe in Nevada.
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 →
Ash Meadows220011994
Nelson120071997
Bald Mtn.120181993
Virgin Creek119991995
Nixon120221988
Fallon119981995
Dobbin Creek120111993

Western Grebe Population Trend in Other States

arizonacaliforniacoloradoidahokansasminnesotamontananebraskanew-mexiconorth-dakotaoregonsouth-dakotautahwashingtonwyoming

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