Many protected areas have multiple uses. Na­tional parks may serve recreational needs, for ex­ample, and national forests may be open for logging grazing, and farming operations. The mineral rights m many refuges are privately owned, and some refuges have had oil, gas, and other mineral development. For example, the D'Arbonne Wild­life Refuge in Louisiana, a sanctuary for 145 species of birds, has soil and water pollution and vegetation damage from natural gas wells. Hunting is allowed in more than half of the wildlife refuges in the United States, and military exercises are conducted in several of them. The Air Force, for example, conducts low-flying jet exercises and live-fire exer­cises over portions of the Prieta Wildlife Refuge, an Arizona refuge for bighorn sheep.

Certain parts of the world are critically short of protected areas. Protected areas are urgently needed in tropical rain forests, the tropical grass­lands and savannahs of Brazil and Australia, and dry forests that are widely scattered around the world. The wildlife of tropical deserts is under-protected in northern Africa and Argentina, and the wildlife of many islands and lake systems needs protection.

Restoring Damaged or Destroyed Habitats

Scientists can reclaim disturbed lands and convert them into areas with high biological diversity. The most famous example of ecological restoration has been carried out since 1934 by the University of Wisconsin-Madison Arboretum (Figure 16-16). During that time, several different communities that are native to Wisconsin were carefully devel­oped on damaged agricultural land. These commu­nities include a tall grass prairie, a dry prairie, and several types of pine apple forests.

Restoration or disturbed lands not only creates wildlife habitats but has additional benefits such as the regeneration of soil that has been damaged by agriculture or mining. The disad­vantages of restoration include the expense and the amount of time it requires to restore an area. Even so, restoration is an important aspect of wildlife conservation.

Zoos, Aquaria, Botanical Gardens, and Seed Banks

Zoos, aquaria, and botanical gardens often make attempts to save species that are on the brink of extinction. Eggs may be collected from the wild, or the remaining few animals may be captured and bred in zoos and other research environments. Spe­cial techniques, such as artificial insemination, embryo transfer, and foster parenting, are used to increase the number of offspring (Figure 16-17). There have been a few spectacular successes in captive breeding programs, in which large enough numbers of a species have been produced to re­establish small populations in the wild (see Focus On: Reintroducing Endangered Species to the Wild). Whooping cranes, which had declined to the critically low population of 15 in 1941, now number over 100. Conservation biologists are hop­ing to have the whooping crane removed from the Endangered species list and classified as only threatened by the year 2000.

Attempting to save a species on the brink of extinction is prohibitively expensive.

Seed Banks Seed collections called seed banks exist around the world. They offer the advantage of storing a large amount of plant genetic material in a very small space. Seeds stored in seed banks are safe from habitat destruction. There have even been some instances of seeds from seed banks being used to reintroduce to the wild a plant species that was eliminated by habitat destruction.

There are also some disadvantages to seed banks, however. First, many types of plants, such as potatoes and orchids, cannot be stored as seeds. Second, seeds don't remain viable (alive) indefi­nitely, so periodically they must be germinated and new seeds collected.

Conservation Organizations

Conservation organizations are an essential part of the effort to maintain biological diversity (see Ap­pendix II). They help to educate policy makers and the public about the importance of biological di­versity- to certain instances they serve as cata­lysts by galvanizing public support for important wildlife preservation efforts. They also provide financial support for conservation projects, from basic research to the purchase of land that is a critical habitat for a particular organism or group of organisms.

The International Union for Conservation of Nature and Natural Resources (IUCN) assists countries with wildlife conservation projects. It and other conservation organizations are currently as­sessing how effective established wildlife areas are in maintaining biological diversity. In addition, IUCN and the World Wildlife Fund have identified major conservation priorities by determining which biomes and ecosystems are not represented by protected areas. IUCN maintains a data bank on the status of the world's species material is published in Red Data Bunks plants, animals, and habitats.

Policies and Laws

In 1973 the Endangered Species Act was passed in the United States, authorizing the U.S. Fish and Wildlife Service to protect from extinction endangered and threatened species in the United States and abroad. Since the passage of the act, approximately 600 species in the United States and more than 500 species worldwide have been endangered or threatened. The Endangered Species Act makes it illegal to sell or buy any product made from an endangered or threatened species.

The Endangered Species Act, which was up dated in 1982, 1985, and 1988 and is scheduled to be reauthorized by Congress in 1992, is considered one of the strongest pieces of environmental legislation in the United States, in part because spec.

are designated as endangered or threatened entirely on biological grounds—economic considerations cannot influence the designation. The Endangered Spades Act has also been one of the most contro­versial pieces of environmental legislation because it has interfered with several federally funded de­velopment projects.

Some critics—notably business interests— view the Endangered Species Act as an impedi­ment to economic progress. The construction of Tennessee's Tellico Dam was halted in 1977, for example, because it would have altered the habitat of an endangered fish called a snail darter. More recently, to protect the habitat of the spotted owl, the timber industry has been blocked from logging old-growth forest in certain parts of the Pacific Northwest. Those who defend the act point out that, of 34,000 past cases of endan­gered species versus "development," only 21 cases could not be resolved by some sort of compromise. The route of a new Illinois highway that would have destroyed a small population of the endan­gered prairie bush clover, for example, was changed to accommodate the plant's habitat. Also, when the black-footed ferret was reintroduced on the Wyoming prairie, it was classified as an "experi­mental, nonessential species" so that its reintroduction would not block ranching and mining in the area. Thus, the ferret release program obtained the support of local landowners, support that was deemed crucial to its survival in the wild.

Defenders of the Endangered Species Act agree that it is not perfect. Few endangered species have recovered enough to be removed from protection. The law is geared more to saving a few popular or unique endangered species rather than the much larger number of less glamorous species that per­form valuable ecosystem services; yet it is the less glamorous organisms such as fungi and insects that dominate ecosystems and contribute most to their functioning. Conservationists would like to see the Endangered Species Act strengthened in such a way us to preserve whole ecosystems and maintain complete biological diversity rather than attempt­ing to save individual endangered species.

International Policies and Laws the World Conservation Strategy, a plan designed to con­serve biological diversity worldwide, was formu­lated in 1980 by the IUCN, the World Wildlife Fund, and the United Nations Environment Pro­gram. In addition to conserving biological diversity, the World Conservation Strategy seeks to preserve the vital ecosystem processes upon which humans depend for survival and to develop sustainable uses of living organisms and ecosystems. Many countries are in varying stages of developing a national conservation strategy, a detailed plan of wildlife con­servation for a specific country.

The exploitation of endangered species can be somewhat controlled through legislation. At the international level, 87 countries now participate in the Convention on Trade in Endangered Species of Wild Flora and Fauna, which bans hunting, captur­ing, and selling of endangered and threatened spe­cies. Unfortunately, enforcement of this treaty var­ies from country to country, and even where enforcement exists, the penalties are not very se­vere. As a result, illegal trade in rare, commercially valuable species countries.