Land Protection
Many governments have been quite active in preserving natural areas within their jurisdiction. If effort is measured by the percentage of the natural landscape so protected, the little country of Costa Rica in Central America would be a winner. The Nature Conservancy is the non-profit organization that has probably preserved the most land worldwide. The Trust for Public Land (TPL) is an American land conservation organization that preserves natural areas. There are numerous local organizations working to directly preserve land by using privately donated funds. The Peninsula Open Space Trust has been active in the San Francisco Bay Area.
International Advocates
The World Conservation Union’s mission is to influence, encourage and assist societies throughout the world to conserve the integrity and diversity of nature and to ensure that any use of natural resources is equitable and ecologically sustainable. The World Wildlife Fund directs its conservation efforts toward three global goals: saving endangered species, protecting endangered habitats and addressing global threats such as toxic pollution, over-fishing and climate change. Conservation International aims to conserve the Earth's living heritage, our global biodiversity, and to demonstrate that human societies are able to live harmoniously with nature. The Global Forest Watch is an international organization that works toward preserving the remaining natural forests worldwide.
North American Advocates
The Wilderness Society focuses on advocating wilderness preservation in the United States through government action. The Wildlands Project works to reconnect the continent beginning with "MegaLinkages"--vast pathways that tie natural places together. Within each continental MegaLinkage it proposes regional systems of core protected areas connected to one another by "wildlife linkages," mosaics of public and private lands that provide safe passageways for wildlife to travel freely from place to place. The Rewilding Institute works to advance continental-scale conservation in North America, particularly the need for large carnivores and a permeable landscape for their movement.
Information
The International Union for Conservation of Nature and Natural Resources maintains a database of endangered species throughout the world. The World Wildlife Fund has a map-driven, searchable database of more than 26,000 species worldwide, with a powerful search tool that allows users to discover where species live or explore wild places to find out what species live there. Conservation International maintains information on biodiversity hotspots around the world. World deer provides information on deer species throughout the world. Wilderness.net provides a database regarding wilderness in the USA.