Aldo Leopold (January 11, 1887 – April 21, 1948) was an American author, scientist ecologist, forester, and environmentalist. He was a professor at the University of Wisconsin and is best known for his book A Sand County Almanac (1949), which has sold over two million copies. He was influential in the development of modern environmental ethics and in the movement for wilderness conservation. His ethics of nature and wildlife preservation had a profound impact on the environmental movement, with his biocentric or holistic ethics regarding land. He emphasized biodiversity and ecology and was a founder of the science of wildlife management.

Early on Leopold was assigned to hunt and kill bears, wolves, and mountain lions in New Mexico. Local ranchers hated these predators because of livestock losses. However, Leopold came to respect the animals. He developed an ecological ethic that replaced the earlier wilderness ethic that stressed the need for human dominance. Rethinking the importance of predators in the balance of nature resulted in the return of bears and mountain lions to New Mexico wilderness areas.

By the 1930s Leopold was the nation's foremost expert on wildlife management. He advocated the scientific management of wildlife habitats by both public and private landholders rather than a reliance on game refuges, hunting laws, and other methods intended to protect specific species of desired game. Leopold viewed wildlife management as a technique for restoring and maintaining diversity in the environment rather than primarily as a means of producing a shootable surplus. (Full article...)