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

White-faced Ibis Population Trend in Nevada

All statesWetland birds

White-faced Ibis in Nevada has surged: up 30× on the route-weighted index since 1992.

30×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 →
15Routes 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 →
34YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable White-faced Ibis 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 increasecomputed 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 →

White-faced Ibis has surged in Nevada: up 30× on the route-weighted index since 1992.

White-faced Ibis Population Forecast in Nevada

If the recent trend holds, White-faced Ibis in Nevada is projected to fall about 73% by 2029 — from 12 in 2024 to a central estimate of 3.2 (95% range 0.00–87). A 5-year backtest shows a typical error of ±176.7%, with 100% of held-out values landing inside the 95% band.

-73%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 →
3.2Projected 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 →
0.00–8795% 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 →
±176.7%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, White-faced Ibis in Nevada is projected to fall about 73% by 2029 — from 12 in 2024 to a central estimate of 3.2 (95% range 0.00–87). A 5-year backtest shows a typical error of ±176.7%, with 100% of held-out values landing inside the 95% band.19902029
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 →
20258.10.0092
20266.90.0090
20275.60.0089
20284.40.0088
20293.20.0087

White-faced Ibis Survey Routes in Nevada

Routes recording White-faced Ibis 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 →
Ruby Valley 232520242004
Fallon13120231992
Hiko10520211998
Carson River2420022001
Cortez2420222018
Ruby Valley2020011997
Chimney Res.1620172016
Piute Mdws820182018
Majors Place820191990
Dobbin Creek720181998
Gardnerville 2720182013
Virgin Creek320152015
Gardnerville220122004
Bald Mtn.120152015
Ash Meadows120162012

White-faced Ibis Population Trend in Other States

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