Humboldt Bay National Wildlife Refuge is located on Humboldt Bay, on the California North Coast near the cities of Eureka and Arcata. The refuge exists primarily to protect and enhance wetland habitats for migratory water birds using the bay area, including tens of thousands of shorebirds, ducks, geese, swans, and the black brant. Humboldt Bay National Wildlife Refuge, along with other public and private lands around Humboldt Bay, is one of the key stopovers for the millions of migratory birds that rely on the Pacific Flyway.