Located in a transition zone between the Sonoran and Mojave deserts, the 4760 acre Mission Creek Preserve has a rich species composition, with flora and fauna representing both deserts. Visitors are surprised to discover the center of the preserve is a lush wetlands juxtaposed with extensively eroded painted hills and Mount San Gorgonio looming in the background. The wetlands and perennial stream are important habitat the endangered least Bell's vireo and southwestern willow flycatcher. The preserve hosts deer, bear, big horn sheep and mountain lions and has spectacular displays of spring wildflowers in wet years. The preserve trail system leads onto the Pacific Crest Trail which is two miles from the stone house group campground.