With so many species facing extinction, conservationists have their work cut out. Conservationists try to protect habitats and provide safe places for threatened animals to thrive, but the activities of ordinary people can often also have an adverse effect on the future of natural habitats.
People give many reasons why wildlife should be conserved. Some argue that if all the forests were cleared and the oceans polluted, the delicate balance of nature would be so ruined that Earth would not be able to support any life, including humans. Others suggest that if vulnerable species were allowed to die, the natural world would not be sufficiently diverse to cope with future changes in the environment. Another reason to save diversity is that we have not yet fully recorded it. Also, there are undoubtedly many as yet unknown species - especially of plants - which could be useful to humankind, for example in the field of medicine. But perhaps the strongest argument for the conservation of wildlife is that it would be totally irresponsible to let it disappear.
Whatever the reasons, the best way to protect species in danger of being wiped out is to protect their habitats so that the complex communities of plants and animals can continue to live. However, with the human population growing so rapidly, people are often forced to choose between promoting their own interests and protecting wildlife. Of course, people invariably put themselves first, which means that the conservationists have to employ a range of techniques in order to save wildlife.
In many countries it has now become illegal to hunt certain endangered animals, or to trade in any products made from their bodies. Whales, gorillas and elephants are protected in this way. Many governments and charitable organizations have also set up wildlife reserves, where the animals stand a good chance of thriving. The oldest protected areas are in North America and Europe, where it is illegal to ruin areas of forest wilderness and wetland. Consequently, these places have become wildlife havens. Other protected areas include semi-natural landscapes which double as beauty spots and tourist attractions. Although these areas often have to be extensively altered and managed to meet the needs of the visitors, most still support wildlife communities.
In the developing world, wildlife refuges are a newer phenomenon. Huge areas of Africa's savannahs are protected and populated with many amazing animals. However, the enormous size of these parks makes it very hard to protect the animals, especially elephants and rhinoceroses, from poachers.
Large areas of tropical forests are now protected in countries such as Brazil and Costa Rica, but often conservation efforts come too late because many animals have either become rare or are completely absent after years of human damage. However, several conservation programmes have reintroduced animals bred in zoos into the wild.
To reintroduce a group of zoo-bred animals successfully into the wild, conservationists need to know how the animal fits into the habitat and interacts with the other animals living there. In addition, for example when trying to reintroduce orang-utans to the forests of Borneo, people have to teach the young animals how to find food and fend for themselves.
Once zoos were places where exotic animals were merely put on display. Such establishments were increasingly regarded as cruel. Today, the world's best zoos are an integral part of conservation. Several animals, which are classified as extinct in the wild, can only be found in zoos where they are being bred. These breeding programmes are heavily controlled to make sure that closely related animals do not breed with each other. Later, individual animals may be sent around the world to mate in different zoos to avoid in-breeding.
A full understanding of how animals live in the wild is also vitally important when conservationists are working in a habitat that has been damaged by human activity. For example, in areas of rainforest which are being heavily logged, the trees are often divided into isolated islands of growth surrounded by cleared ground. This altered habitat is no good for monkeys, which need large areas of forest to swing through throughout the year. The solution is to plant strips of forest to connect the islands of untouched habitat, creating a continuous mass again.
Another example of beneficial human intervention involves protecting rare frogs in the process of migrating to a breeding pond. If their migration necessitates crossing a busy road, it is likely that many of them will be run over. Conservationists now dig little tunnels under the roads so that the frogs can travel in safety. Similar protection schemes have been set up for hedgehogs and ducks, to allow them safe passageways.