Resource Management


Delta National Wildlife Refuge is at the terminus of the central flyway for North American waterfowl. It is also one of the last areas of land available to neotropical migrants crossing the Gulf of Mexico on the way to Central and South America. The Refuge’s wetlands are key to supporting many species of these migratory birds, as well as wintering waterfowl and shorebirds. The Refuge's coastal wetlands also provide a nursery for several species of marine life which are the lifeblood of the sport and commercial fisheries of this region.

Resource management activities on the Refuge include:

  • Marsh building. The Refuge is part of a dynamic river delta system. Land subsidence and storm action have interacted to convert marsh to open water by allowing salt water to move into formerly brackish or fresh water zones, killing less salt-tolerant vegetation and causing erosion and loss of substrate. Refuge managers counter these forces with strategically located sediment splays (made by artificially breaching the natural levees via a cut or crevasse), to allow sediment to re-nourish the marsh and replace lost sediments. Managers also work with U.S. Army Corps of Engineers to place dredging spoils along shorelines to build land and protect the marsh from erosion.
  • Maintaining sanctuary for wintering waterfowl. Wintering ducks and geese have significant energy and nutrition requirements to support molting, growing new feathers, and getting ready for spring migration. Disturbance-free habitat allows waterfowl to prepare for spring migration and reproduction. Refuge managers and law enforcement work to maintain a sanctuary for wintering waterfowl in the interior of the Refuge. Managers also work to maintain a productive mix of emergent marsh and open water to provide food and cover for migratory bird species.
  • Monitoring migratory bird and wintering waterfowl use of the Refuge. U.S. Fish and Wildlife Service biologists conduct aerials surveys of bird populations while observing and evaluating marsh habitat. 
  • Removal of invasive species such as feral hogs, which cause habitat destruction.
  • Monitoring the extensive oil and gas activities that occur on the Refuge, working with the operators and partners to minimize the risk of oil spills, and mitigating the spills that occur.

Trapping Occurs on this Refuge

Trapping is a wildlife management tool used on some national wildlife refuges. Trapping may be used to protect endangered and threatened species or migratory birds or to control certain wildlife populations. The U.S. Fish and Wildlife Service also views trapping as a legitimate recreational and economic activity when there are harvestable surpluses of fur-bearing mammals. Outside of Alaska, refuges that permit trapping as a recreational use may require trappers to obtain a refuge special use permit. Signs are posted on refuges where trapping occurs. Contact the refuge manager for specific regulations. Click here for more information on trapping within the National Wildlife Refuge System.