 Snakes such as the ringneck snake , western yellow @-@ bellied racer , striped <unk> , and Pacific gopher snake live in the oak savanna region . Birds such as the oak titmouse , ash @-@ throated flycatcher , white @-@ breasted nuthatch , western bluebird , violet @-@ green swallow , acorn woodpecker , black @-@ headed grosbeak , and American kestrel have also been found in this region . The rocks are known to be the northernmost place blue @-@ gray gnatcatchers inhabit . Gall wasps live in this area , often creating galls in oak trees by injecting their larva into their leaves and branches . 
