BirdAnalyst
Species · BCR 33 · BBS 2025 Release · 1966–2024

White-faced Ibis In Sonoran and Mojave Deserts

All regionsSonoran and Mojave DesertsWetland birds

White-faced Ibis in Sonoran and Mojave Deserts has surged: up 131% on the route-weighted index since 1985.

+131%Since 1985TrendPercent 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 RegionSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
41YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable SignalsNotable 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 Sonoran and Mojave Deserts: up 130% on the route-weighted index since 1985.

White-faced Ibis In Sonoran and Mojave Deserts Population Forecast

If the recent trend holds, White-faced Ibis in Sonoran and Mojave Deserts is projected to rise about 38% by 2029 — from 8.1 in 2024 to a central estimate of 11 (95% range 0.00–29). A 5-year backtest shows a typical error of ±814.6%, with 100% of held-out values landing inside the 95% band.

+38%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 →
11Projected 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 →
0.00–2995% 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 →
±814.6%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 Sonoran and Mojave Deserts is projected to rise about 38% by 2029 — from 8.1 in 2024 to a central estimate of 11 (95% range 0.00–29). A 5-year backtest shows a typical error of ±814.6%, with 100% of held-out values landing inside the 95% band.19812029
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 →
2025100.0028
2026110.0028
2027110.0029
2028110.0029
2029110.0029

Routes In Sonoran and Mojave Deserts

Routes recording White-faced Ibis in Sonoran and Mojave Deserts.
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 →
BrawleyCALIFORNIA2052012
NilandCALIFORNIA1852024
Alamo RiverCALIFORNIA1221992
Palo VerdeCALIFORNIA582024
Cibola LakeARIZONA182012
Calif CityCALIFORNIA132012
Ash MeadowsNEVADA12016

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