U.S. Forest Service, National Park Service, U.S. Army Corps of Engineers, Bureau of Land Management and the U. S Fish and Wildlife Service, as well as numerous other Federal Agencies.
Texas Parks and Wildlife Department and Texas Forest Service. Each state has a similar entity or entities.
Municipalities, counties, or other local government entities often manage parks, museums, zoos or nature centers which employ park managers or interpreters.
Resorts and commercial camping, youth camps, ecotourism companies, outfitters, museums, nature centers.