12/31/1996 117

PETITIONED FILED TO LIST SOUTHERN CALIFORNIA PLANT AS ENDANGERED-HCPs DRIVING IT EXTINCTION

The Southwest Center and the California Native Plant Society have submitted a petition to the Fish and Wildlife Service to list the San Diego ambrosia as endangered under the ESA. Always rare in the areas that today comprise Riverside, San Diego, and Baja California, in recent years San Diego ambrosia has been nearly wiped out by development. Two populations persist in Riverside County near Skunk Hollow and Lake Elsinor, and twelve remain in San Diego County in the San Luis Rey, San Diego, and Sweetwater river drainages. As few as three viable United States populations are all that may remain one year from today due to pending development.

The plight of the San Diego ambrosia is indicative of common problems with southern California habitat conservation planning efforts. All populations of this species "preserved" by the City of San Diego's Multiple Species Conservation Program for example were misidentified. Numerous ambrosia populations may have been lost while populations of another similar species were set-aside.