Don Edwards San Francisco Bay National Wildlife Refuge

Don Edwards San Francisco Bay National Wildlife Refuge is the largest urban national wildlife refuge in the United States, encompassing over 30,000 acres of open bay, salt marsh, mudflat, salt pond, and upland habitats along the southern end of San Francisco Bay. More than 280 bird species have been documented, and the refuge supports one of the highest concentrations of wintering shorebirds in North America.

The Environmental Education Center in Alviso and the Visitor Center in Fremont provide excellent trail access to prime birding areas. At low tide, the mudflats attract vast numbers of Western Sandpipers, Dunlin, and Long-billed Dowitchers, while the salt ponds host American Avocets, Black-necked Stilts, and Snowy Plovers. The refuge is a critical stronghold for the endangered Ridgway's Rail and Salt Marsh Harvest Mouse.