Bird Conservation Region 33

Sonoran and Mojave Deserts

An ecological region spanning Arizona, California, Nevada, with 89 survey routes. BCRs are the natural unit for bird trends.

What Is Moving Here

long arc declinecomputed index

Eared Grebe has collapsed in Sonoran and Mojave Deserts: down 98% on the route-weighted index since 1980.

long arc increasecomputed index

Common Yellowthroat has surged in Sonoran and Mojave Deserts: up 12× on the route-weighted index since 1970.

long arc declinecomputed index

LeConte's Thrasher has collapsed in Sonoran and Mojave Deserts: down 97% on the route-weighted index since 1970.

long arc increasecomputed index

Great-tailed Grackle has surged in Sonoran and Mojave Deserts: up 969% on the route-weighted index since 1970.

long arc declinecomputed index

Brewer's Blackbird has collapsed in Sonoran and Mojave Deserts: down 97% on the route-weighted index since 1970.

long arc increasecomputed index

Black Phoebe has surged in Sonoran and Mojave Deserts: up 827% on the route-weighted index since 1971.

How Guilds Are Faring

Survey Routes

Species By Family

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