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

Yellow Warbler In Sonoran and Mojave Deserts

All regionsSonoran and Mojave DesertsForest birds

Yellow Warbler in Sonoran and Mojave Deserts has surged: up 89% on the route-weighted index since 1971.

+89%Since 1971TrendPercent 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 →
42Routes 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 →
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 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 →

Yellow Warbler has surged in Sonoran and Mojave Deserts: up 89% on the route-weighted index since 1971.

Forecast

If the recent trend holds, Yellow Warbler in Sonoran and Mojave Deserts is projected to rise about 54% by 2029 — from 0.60 in 2024 to a central estimate of 0.92 (95% range 0.14–1.7). A 5-year backtest shows a typical error of ±117.5%, with 100% of held-out values landing inside the 95% band.

+54%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 →
0.92Projected 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 →
0.14–1.795% 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 →
±117.5%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, Yellow Warbler in Sonoran and Mojave Deserts is projected to rise about 54% by 2029 — from 0.60 in 2024 to a central estimate of 0.92 (95% range 0.14–1.7). A 5-year backtest shows a typical error of ±117.5%, with 100% of held-out values landing inside the 95% band.19692029
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 →
20250.860.071.6
20260.880.091.7
20270.890.111.7
20280.910.121.7
20290.920.141.7

Routes In Sonoran and Mojave Deserts

Routes recording Yellow Warbler 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 →
Jean LakeNEVADA682007
Cutter 2ARIZONA352018
Anza BorregoCALIFORNIA82024
Willow SpgsCALIFORNIA71971
Palo Verde 2ARIZONA42024
DatelandARIZONA32016
AntaresARIZONA32018
Cactus ForestARIZONA32012
Red Rock 2ARIZONA32019
Kelso ValleyCALIFORNIA32018
QuartzsiteARIZONA22024
New RiverARIZONA22016
Alamo Res.ARIZONA22019
ArabyARIZONA22006
Casa GrandeARIZONA22023
Eureka ValCALIFORNIA22004
PearblossomCALIFORNIA22024
BeattyNEVADA22015
FlorenceARIZONA11988
RivieraARIZONA12024
Cibola LakeARIZONA12018
Palo VerdeARIZONA12012
Red RockARIZONA12011
WickenburgARIZONA12023
HopeARIZONA11996

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