Protected Area

The International Union for the Conservation of Nature (IUCN) recognizes six categories of protected areas:

• Category 1 is the highest level of protection. This category includes scientific reserves and wilderness areas. They are managed to maintain native species and natural ecosystems, although use for research may be allowed. These types of highly protected areas are often relatively small, and present in most U.S. states.
• Category 2 includes national parks and equivalent reserves. These are managed primarily to protect species and ecosystems, although outdoor recreation and ecotourism is usually permitted. Two famous protected areas in the United States are Yellowstone and Yosemite National Parks.
• Category 3 includes national monuments and geological phenomena. Sites of aesthetic or cultural importance are also included.
• Category 4 includes habitatand species-management areas, intended to conserve conditions required in support of productive populations of hunted species.
• Category 5 includes protected landscapes and seascapes. It is intended to sustain recreational use of such areas by humans, while also accommodating the needs of most wild species and ecosystems.
• Category 6 includes managed-resource protected areas, which are primarily managed to yield a sustainable harvest of renewable natural resources (such as timber), while also accommodating the needs of native species and ecosystems.

In 1997, there were about 10,400 protected areas covering a total of 2.1 billion acres (841 million hectares) worldwide (IUCN categories 1-5; World Resources Institute, 1998). Of this total area, about 4,500 sites, amounting to 1.2 billion acres (499 million ha), were fully conserved (IUCN categories 1-3) and could be considered true protected areas.