Californian Coasts and Mountains

The Californian Coasts and Mountains sub-region of the Sonoran Joint Venture comprises southern California, Baja California, and the Pacific islands off the coast of these two states. This sub-region includes all or parts of Bird Conservation Regions 32, 39, and 63. The Mediterranean climate of hot, dry summers and cool, moist winters creates conditions for vegetation that includes coastal sage scrub, chaparral, pinyon-juniper, live oak woodlands, and pine as elevation increases. These habitats support such birds as California Gnatcatcher, California Quail, Mountain Quail, Wrentit, California Thrasher, Nuttall’s Woodpecker, Oak Titmouse, Bell’s “Least” Vireo, and California Condor. The coastal areas provide habitat for several waterfowl and shorebird species and are an important wintering area for Pacific Brant, Marbled Godwit, American Avocet, and Surfbird. The Channel Islands offer breeding sites for 14 species of seabirds, such as Ashy, Leach’s, and Black storm-petrels, Black Oystercatcher, and Cassin’s Auklet. Most of the world’s population of Ashy Storm-Petrel and Scripp’s (formerly Xantus’s, in part) Murrelet nest on a small number of offshore islands within this sub-region. A sizable proportion of the Elegant Tern and Heermann’s Gull populations spend the non-breeding season here, and millions of Sooty Shearwaters gather in pelagic waters each fall, joined by large numbers of other seabirds.

Sub-regions of the Sonoran Joint Venture