The National Wildlife Refuge System Improvement Act defines a unifying mission for all refuges, including a process for determining compatible uses on refuges, and requiring that each refuge be managed according to a CCP.
The NWRS Improvement Act expressly states that wildlife conservation is the priority of Refuge System lands and that the Secretary of the Department of the Interior shall ensure that the biological integrity, diversity, and environmental health of refuge lands are maintained.
Each refuge must be managed to fulfill the specific purposes for which the refuge was established and the Refuge System mission. The first priority of each refuge is to conserve, manage, and if needed, restore fish and wildlife populations and habitats according to its purpose.
See the NWRS Improvement Act