Defenders of Wildlife is dedicated to the protection of all native wild animals and plants in their natural communities.
National Wildlife Federation focuses on five core issues (Endangered Habitat, Water Quality, Land Stewardship, Wetlands, and Sustainable Communities), and pursues a range of educational projects, and activist, advocacy, and litigation initiatives, within these core areas.
The Wilderness Society calls for "spirited people who will fight for the freedom of the wilderness." The site gives updates on efforts to preserve wild spaces.
World Wildlife Fund is dedicated to protecting the world's wildlife and wildlands. WWF's U.S. web site has updates on their environmental efforts, like the passage of laws they've lobbied for, and also gives results of scientific reports, such as their recent report on the effects of global warming.
The Jane Goodall Center For Excellence in Environmental Studies, a collaboration between the Jane Goodall Institute and Western Connecticut State University.