Management of federal lands is complicated
There are 425 units in the National Park System but only 63 National Parks created by acts of Congress. There are 133 National Monuments created by Congress or by Presidential proclamation (using the Antiquities Act of 1906) but only 86 are managed by the National Park System. Wilderness areas are managed by the National Park Service, Bureau of Land Management, US Fish and Wildlife Service, and US Forest Service.
Currently, approximately 640 million acres of surface land are managed by the federal government, accounting for nearly 28% of the 2.3 billion acres of land in the 50 states and
District of Columbia. Four federal land management agencies administer 606 million acres (95%) of these federal lands:
1) Forest Service, in the Department of Agriculture, manages the 193 million acre National Forest System.
2) Bureau of Land Management (BLM), in the Department of the Interior (DOI), manages 244 million acres of public lands.
3) U. S. Fish and Wildlife Service, in DOI, manages 89 million acres as part of the National Wildlife Refuge System.
4) National Park Service, in DOI, manages 80 million acres in the National Park System.
The remaining federal acreage is managed by several other agencies, including the
Department of Defense.[Source: Wikipedia]