This bill directs the U.S. Fish and Wildlife Service (USFWS) to establish the Western Riverside County National Wildlife Refuge in California. USFWS must include within the boundaries of the refuge the lands and waters within the Western Riverside County Multiple Species Habitat Conservation Plan Area that are owned by the federal government, a state, or a political subdivision of a state upon the establishment of the refuge. USFWS may enter into cooperative agreements with the State of California, any of its political subdivisions, or any other persons to (1) manage lands that are owned by California, the subdivision, or the other person and located within the refuge; (2) promote public awareness of the natural resources of the conservation area; or (3) encourage participation by the public in the conservation of such resources. USFWS may acquire by donation, purchase, or exchange the lands and waters or interests in them (including conservation easements) within the refuge, except those that are owned by California and its political subdivisions may be acquired by donation only. Federal property in the refuge must be assessed for inclusion in the refuge and must be transferred to USFWS if deemed suitable for inclusion.