Large numbers of other bird species can be found on the refuge, with numbers peaking during the spring and fall migrations. Large numbers of wading birds nest on the refuge, and thousands of shorebirds can be found on tidal mudflats and deltaic splays. Thousands of shorebirds use the refuge as a wintering area, and also as a resting and staging area during migration. Commonly observed species include greater and lesser yellowlegs, long-billed dowitchers, dunlins, western sandpipers, Wilson's plovers, killdeer, and willets. The most commonly observed species include American kestrels, northern harriers, red-tailed hawks, and turkey vultures.
Ospreys are common winter visitors to the refuge.
Deer are frequently observed by the refuge staff on the natural pass banks, manmade spoil banks, and the marshes associated with these features. Swamp rabbits are found over much of the refuge, and populations appear to be stable. The most abundant of these is the nutria. The marshes and waterways of the Delta NWR support a diversity of fish species. Speckled trout, redfish, flounder, blue crabs, and shrimp are important saltwater species found on the refuge.