Beginning with the next full fiscal year and for each fiscal year thereafter, all revenues received by the Secretary of the Interior from the sale or other disposition of animals, salmonoid carcassas, timber, hay, grass, or other products of the soil, minerals, shells, sand, or gravel, from other privileges, or from leases for public accommodations or facilities incidental to but not in conflict with the basic purposes for which those areas of the National Wildlife Refuge System were established, during each fiscal year in connection with the operation and management of those areas of the National Wildlife Refuge System, National Fish Hatcheries, or other areas, that are solely or primarily administered by him, through the United States Fish and Wildlife Service, shall be covered into the United States Treasury and be reserved in a separate fund for disposition as hereafter prescribed. Amounts in the fund shall remain available until expended, and may be expended by the Secretary without further appropriation in the manner hereafter prescribed. The National Wildlife Refuge System (hereafter referred to as the “system”) includes those lands and waters administered by the Secretary as wildlife refuges, lands acquired or reserved for the protection and conservation of fish and wildlife that are listed pursuant to section
1533 of this title as endangered species or threatened species, wildlife ranges, game ranges, wildlife management areas, and waterfowl production areas established under any law, proclamation. Executive, or public land order.