The California gnatcatcher, Polioptila californica californica , is a federally listed threatened species dependent upon coastal sage scrub. The California gnatcatcher is an insectivorous species. It feeds on arthropods gleaned from California sagebrush Artemisia californica and flat-topped buckwheat Eriogonum fasciculatum .
Gnatcatchers require large patches of coastal sage scrub.
Most nests are constructed less than 1m off the ground. These ranges tend to be smaller near the coast and larger in the drier, sparser inland areas. The existing stands of potential California gnatcatcher habitat are in southern Orange Country and on Camp Pendleton, as shown in figure 67 . The concentrations are located in coastal zone and foothills areas on Camp Pendleton, which are managed for military training, and Orange County in areas that are being considered for protection under several conservation plans. Plans Build-Out, shown in figure 68 threatens about half of the present 300,000ha.