ENDANGERED SPECIES
The Scope of the Problem

DODOES have become a symbol of extinction. The last of these flightless birds died about 1680 on the island of Mauritius. Many of the species presently at risk live on islands too. In the last 400 years, 85 out of 94 species of birds known to have disappeared have been island birds.

Animals on vast continents are also in danger of extinction. Consider the tigers that once roamed throughout Russia. Now only the Amur subspecies remains in Siberia, and its numbers have dwindled to a mere 180 to 200. The tigers of southern China reportedly number only 30 to 80. In Indochina these animals face extinction "within ten years," reports The Times of London. Likewise, in India, home to some two thirds of the world's tigers, authorities estimate that these majestic creatures could be extinct in a decade.

Rhinoceroses and cheetahs are on the decline. Only about a thousand giant pandas are now found in the wild. Pine marten are nearly extinct in Wales, and red squirrels "may disappear from mainland England and Wales in the next ten to 20 years," claims The Times. Across the Atlantic in the United States, bats are the most endangered land mammal.

The outlook in the world's oceans is no less bleak. The Atlas of Endangered Species labels marine turtles as "perhaps the most endangered group" of sea creatures. Amphibians appear to fare better; however, according to New Scientist magazine, 89 species of amphibians have come to be "at risk of extinction" in the last 25 years. Some 11 percent of the world's bird species face extinction too.*

But what of smaller creatures, such as butterflies? The picture is similar. Over a quarter of Europe's 400 butterfly species are in danger—19 being threatened by imminent extinction. Britain's large tortoiseshell butterfly joined the dodo on the list of extinct species in 1993.

Growing Concern

How many species of creatures become extinct every year? The answer depends on which expert you ask. Though scientists disagree, all accept the fact that many species are in danger of becoming extinct. Ecologist Stuart Pimm observes: "The controversy about how fast we are losing [species] is fundamentally a debate about our future." He adds: "Over the past centuries, we have accelerated the rate of extinction of species far beyond the natural rate. Our future is poorer as a consequence."

Our planet, Earth, is like a house. Some people who care about endangered species study ecology, a term coined in the latter part of the 19th century from the Greek word oi'kos, "a house." This field of interest focuses on relationships between living things and their environment. The 19th century saw a growing interest in conservation, heightened no doubt by reports of extinctions. In the United States, this led to the establishment of national parks and protected areas that offer creatures sanctuary. Presently, there are an estimated 8,000 internationally recognized wildlife protection areas worldwide. Together with a further 40,000 sites that help maintain habitat, they constitute nearly 10 percent of the world's land area.

Many concerned people now espouse so-called green causes, either through movements that publicize the threats of extinction or those that simply educate people about the interdependency of life. And since the 1992 Rio Earth Summit, a greater awareness of environmental issues generally characterizes government thinking.

The problem of endangered species is global and growing. But why? Are any attempts to prevent the extinction of species currently successful? And what of the future? How are you involved? Our next articles offer answers.

*  An extinct species is defined as one that has not been seen in the wild for 50 years, whereas an endangered species refers to those in danger of extinction if there is no change in their current circumstances.