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

Pied-billed Grebe Population Trend in Nevada

All statesWetland birds

Pied-billed Grebe in Nevada has fallen sharply: down 57% on the route-weighted index since 1992.

-57%Since 1992TrendPercent 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 →
10Routes 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 →
31YearsYears 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 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 →

Pied-billed Grebe has fallen sharply in Nevada: down 57% on the route-weighted index since 1992.

Pied-billed Grebe Population Forecast in Nevada

If the recent trend holds, Pied-billed Grebe in Nevada is projected to rise about 80% by 2028 — from 0.11 in 2023 to a central estimate of 0.20 (95% range 0.00–0.91). A 5-year backtest shows a typical error of ±282.3%, with 100% of held-out values landing inside the 95% band.

+80%Change by 2028TrendPercent 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 →
0.20Projected 2028 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–0.9195% 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 →
±282.3%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 Nevada is projected to rise about 80% by 2028 — from 0.11 in 2023 to a central estimate of 0.20 (95% range 0.00–0.91). A 5-year backtest shows a typical error of ±282.3%, with 100% of held-out values landing inside the 95% band.19862028
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 →
20240.200.000.92
20250.200.000.92
20260.200.000.91
20270.200.000.91
20280.200.000.91

Pied-billed Grebe Survey Routes in Nevada

Routes recording Pied-billed 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 →
Cortez220232018
Dobbin Creek220181987
Bald Mtn.120191992
Sand Pass120122012
Ash Meadows120191994
Virgin Creek120161997
Nixon120222022
Fallon120072007
Gardnerville120111994
Beatty119861986

Pied-billed Grebe Population Trend in Other States

alabamaalaskaarizonaarkansascaliforniacoloradoconnecticutdelawarefloridageorgiaidahoillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniasouth-carolinasouth-dakotatennesseetexasutahvermontvirginiawashingtonwisconsinwyoming

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