BirdAnalyst
Species · BCR 33 · BBS 2026 Release · 1966–2025

Costa's Hummingbird In Sonoran and Mojave Deserts

All regionsSonoran and Mojave DesertsForest birds

Costa's Hummingbird in Sonoran and Mojave Deserts has risen sharply: up 56% on the route-weighted index since 1970.

+56%Since 1970TrendPercent 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 →
55Routes 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 →
57YearsYears 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 →

Costa's Hummingbird has risen sharply in Sonoran and Mojave Deserts: up 56% on the route-weighted index since 1970.

Costa's Hummingbird In Sonoran and Mojave Deserts Population Forecast

If the recent trend holds, Costa's Hummingbird in Sonoran and Mojave Deserts is projected to rise about 45% by 2030 — from 0.57 in 2025 to a central estimate of 0.83 (95% range 0.00–1.8). A 5-year backtest shows a typical error of ±38.8%, with 100% of held-out values landing inside the 95% band.

+45%Change by 2030TrendPercent 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 →
0.83Projected 2030 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–1.895% 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 →
±38.8%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, Costa's Hummingbird in Sonoran and Mojave Deserts is projected to rise about 45% by 2030 — from 0.57 in 2025 to a central estimate of 0.83 (95% range 0.00–1.8). A 5-year backtest shows a typical error of ±38.8%, with 100% of held-out values landing inside the 95% band.19682030
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 →
20260.810.001.7
20270.810.001.8
20280.820.001.8
20290.820.001.8
20300.830.001.8

Routes In Sonoran and Mojave Deserts

Routes recording Costa's Hummingbird 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 →
GlamisCALIFORNIA181995
Bates WellARIZONA132023
Willow Beach 2ARIZONA62019
Joshua Tree 2CALIFORNIA62025
Cibola LakeARIZONA42015
Organ PipeARIZONA42023
Willow SpgsCALIFORNIA41977
Anza BorregoCALIFORNIA42025
Cabeza PrietARIZONA32025
WickenburgARIZONA32023
Calif CityCALIFORNIA32012
Eureka ValCALIFORNIA32024
IvanpahCALIFORNIA32019
Iron MtnsCALIFORNIA32011
BlytheCALIFORNIA31979
BeattyNEVADA32024
Alamo Res.ARIZONA22023
Ajo 2ARIZONA22018
OnyxCALIFORNIA21998
Valley WellsCALIFORNIA22019
Kelso ValleyCALIFORNIA22017
Cholla Gard.CALIFORNIA22017
AlamoNEVADA21969
OatmanARIZONA12018
WikieupARIZONA11998

Source: USGS North American Breeding Bird Survey, retrieved 2026-08-14.