An estimated 8 to 10 million different species live on the planet. Of these, only about 1.5 million have been named.
Documented animal extinctions peaked in the 1930s, and the number of extinctions has been declining since then.
Thirty-nine percent of the extinctions resulted from the introduction of nonnative species, 36 percent from habitat destruction, and 23 percent from hunting (for sport and products for sale) and deliberate elimination of a species. The remaining 2 percent became extinct for a variety of causes, including pollution.
More than 75 percent of the land on every continent except Europe is available for wildlife. It is this undeveloped land in developing countries that is of greatest importance to conserving biodiversity over the long term.
Well over a billion hectares of the earths surface have been set aside as protected areas, representing over 10 percent of the land area.
Since 1973, only twenty-three species have been removed from the U.S. Endangered Species list: eight were listed in error a court invalidated the listing of one, seven recovered, and seven became extinct. In other words, there is an equal probability that a species listed on the Endangered species Act will recover or become extinct.
Governments and conservation organizations need to begin to promote harvesting and using wild species rather than stopping such uses.
Trade in wildlife products is of the same order of magnitude as trade in forestry and fish products. In 1986, international trade in primates, ivory, orchids, reptile skins, fur-bearers, and tropical fish was worth $5 billion.
To enhance the probability of sustaining the wild harvest or use, the rural people living in developing countries with wildlife resources must have sufficient incentives to conserve the resources, free from excessive government interference. Environmentalists need to recognize that rural people can be allies in conservation, and not treat them as environmental criminals.
Listing species to achieve legal protection is not working. More land and marine areas are being designated as protected; however, it is difficult to assess how effective protected areas are at conserving biodiversity.