The combination of Assateague Island's natural assets and Chincoteague National Wildlife Refuge's wildlife habitat enhancement has established the area as one of eastern North America's most important shorebird management areas. In regards to numbers of shorebirds using an area during the southward migration, Chincoteague NWR ranks fourth among 454 sites where a census was taken in the U.S., east of the Rockies, and is important for many species on an international scale. The refuge also provides excellent nesting habitat for colonial and other beach nesting birds. Colonial species include common, least, and gull-billed terns, and black skimmers. Willets and oystercatchers nest on the cove side beach and around the natural freshwater marsh in the Hook interior.
Oystercatchers also nest in the dunes.
Two active bald eagle nests are found on the refuge, and eagles can often be seen by the sharp eyed visitor. Refuge's marshes and pools are fished heavily by ospreys, who typically nest on hunting blinds over open water in Assateague Channel and Chincoteague Bay. Osprey populations in the area have recovered from a decline caused by DDT and are once again abundant. Red-tailed hawks nest in forests on the refuge. Large numbers of hawks stop to rest and feed during their fall migration, including kestrels, merlins, sharp-shinned, and Cooper's hawks.