Most endangered species cannot survive any further reductions in their breeding populations, so it is important to prevent their exploitation. The legal mechanism for prohibiting trade in these species or their products is an international agreement called the Convention on International Trade in Endangered Species (CITES). CITES currently prohibits international trade in items such as whale meat, rhinoceros horns, and many species of parrots, orchids, and others.
The recent history of elephant poaching for ivory illustrates how complex it can be to prevent hunting of endangered species. CITES instituted a ban on international trade in African elephant ivory in 1989, but demand for ivory remains strong, especially in Asia. As a result, as we described above, poaching of elephants continues in the forests of central and east Africa, where the animals are threatened. However, some countries, including Malawi and Zambia, have so many elephants that government officials kill them to control populations and prevent the animals from damaging crops. This excess of elephants led to the controversial decision to sanction sales of ivory from Namibia, Botswana, Zimbabwe, and South Africa in 2008, the first such sales in close to a decade. More than 100 tons of elephant tusks—