Madagascar. Arrival and Impact of Man. Endangered Species. Environmental Protection

With a land surface of 587,042 square kilometers, Madagascar is the world's fourth-largest island, approximately the size of Texas. Variations in latitude, altitude, and climate have produced there a number of distinct ecoregions with a high percentage of native species. The island possesses probably the world's greatest concentration of unique flora and fauna: 98 percent of Madagascar's land mammals, 92 percent of its reptiles, 68 percent of its plants, and 41 percent of its indigenous bird species are found nowhere else.

Madagascar's environmental peculiarity stems from its geological origins. Some 150 to 180 million years ago Madagascar split from Africa and settled into its current position in the Indian Ocean, some 400 kilometers from the coast of continental Africa. For millions of years, it has been separated from East Africa by a minimum of 200 kilometers of ocean by the Mozambique Channel notorious for its hazardous winds and currents.

Thus many African species, including the elephant, giraffe, lion, and leopard, are unknown in Madagascar. Moreover, its flora and fauna are as much South American as African in origin: Dinosaur remains suggest a land bridge linked Madagascar to South America, probably via Antarctica, until some 65 million years ago.

Arrival and Impact of Man. The natural environment was a stronger force in Madagascar than in most other areas of comparable size as it possessed no human population until the first millennium се. Even when it began to be settled, its generally mountainous topography (with deserts in the south) ensured scattered and low-density settlement.

Humans have had a major environmental impact over the last 2,000 years. The first settlers introduced new species from Southeast Asia and Africa, some deliberately (such as rice, bananas, dogs, and oxen) and some inadvertently (such as the rat and plasmodium protozoa, the infectious agent of malaria). They probably hunted to extinction such species as the pygmy hippopotamus and the world's largest bird species (Aepyornis maximus), among numerous others.

More harmful than hunting has been the burning of forest to create agricultural plots (central and eastern Madagascar) and pasture (in the south and west). Since the 1980s rapid impoverishment and population growth (averaging 3.2 percent per annum from 1990 to 1995) has driven small farmers ever deeper into the forested hills and enfeebled governmental efforts to protect environmentally endangered areas. Forest wood and charcoal still meets 80 percent of domestic fuel needs.

Also, economic liberalization has attracted foreign investors eager to exploit Madagascar's valuable mineral and precious-stone reserves, many of which lie within environmentally sensitive areas. Although forest still covers 20.2 percent (12 million hectares) of the island's surface, it is disappearing at an annual rate of 2,000 square kilometers and, except in the northeast, primary forest has been largely replaced by secondary growth.

An estimated 97 percent of the island's dry deciduous western forests have been destroyed by burning and clearing for grazing and agriculture. One-third of Madagascar's land area is still burned each year to encourage new grass growth for cattle; the practice causes widespread soil erosion. In the central highlands, human activity has reduced Madagascar's subhumid montane forest to a few fragmented areas where remaining endemic species risk imminent extinction.

Moreover, the 14,000 to 17,000 square kilometers of spiny forest in the semidesert of the south, traditionally less threatened than woodlands because of hunting taboos and lower population density, is increasingly threatened by expanding agriculture, timber exploitation, the flower and pet trades, and migration. Also the El Nino Southern Oscillation (ENSO) event, the chief source of global interannual climate variability, occurs every two to ten years, accentuating the south's vulnerability to drought and famine.

Madagascar's marine waters are extensively fished by other national fleets. Its west-coast mangrove forests are threatened by urban development, erosion (due to tree felling in the highlands), rice cultivation, salt production, overfishing, and petroleum and timber exploitation. In addition, global warming has damaged coral reefs that protect mangroves from strong ocean tides.

Endangered Species. Madagascar's primate species, second only to Brazil in variety, are the world's most endangered. The island's endangered plants have considerable potential economic value. Sales of drugs derived from the rosy periwinkle of the south, used to treat childhood leukemia and Hodgkin's disease (remission rates of 99 and 58 percent respectively), have reached about $160 million a year, while the eastern rain forest contains over 50 rare but potentially exploitable species of wild coffee.

Subequatorial East Coast. Warm and wet throughout the year, this ecoregion possesses extensive marshland and on the interior escarpment supported a tropical rain forest. Twenty-two of the forest's twenty-five mammal species are endangered, including such lemurs as the sifaka and the indri; other endangered animal and plant species include the serpent eagle, red owl, and many freshwater fish and orchids.

Central Highlands. At over 1,300 meters altitude, the highlands experience considerably lower temperature and rainfall levels than the east coast. Dominated by mixed savannah and woodland, the highlands possess a number of minor ecoregions. There are fragmented wetlands and semihumid forests that contain many highly endangered native species, including the Alaotran gentle lemur, several species of shrew, tenrec, and rodent, some twenty-five reptiles, and over twenty amphibians. Of the bird species, the Alaotra little grebe and pochard may already be extinct and several other species are threatened.

The montane zone, comprising ericoid (heathlike) thickets above 1,800 meters on Madagascar's four main massifs, forms another important ecoregion. There, a small number of native mammal, reptile, and amphibian species as well as several native bird species are threatened, mostly by fire used to create cattle pasture.

Western Madagascar. The west supports savannah and woodland, is drier than the center and east, and, as on the plateau, humidity falls progressively as one moves south. Its most vulnerable ecoregion is the coastal mangrove forest, one of the world's ten most endangered forests, only 1.3 percent of which was protected in 2001. There, threatened species include the dugong (an aquatic mammal similar to a sea manatee), turtle species, the Madagascar heron, and other birds.

In the succulent woodlands of the southwest and central regions, hunting threatens the tenrec (a spiny insectivore), fruit bats, and the red-fronted brown lemur. Several endemic bird species are vulnerable, including the Madagascar plover and especially the Madagascar teal, as are the gecko Paroedura vazimba and snake Liophidium chabaudi. Also threatened are native species of trees, exploited for construction wood.

The few remaining fragmented patches of Madagascar's dry, deciduous forest and associated river systems and wetlands are characterized by very high levels of native plants and animals. Endangered species include four of Madagascar's five native and endangered lemurs and two species of tortoise that are possibly the world's rarest: the ploughshare, or spurred, tortoise and the angonoka tortoise.

The South. Once more humid, southern Madagascar became progressively drier from about 2000 все. Much of the interior receives less than 500 millimeters of rainfall, and the southwest coast less than 350 millimeters of rainfall a year. This region is home to the spiny or deciduous thicket, under 3 percent of which is protected. Endangered species include the Aloe suzannae, the palm, Dypsis decaryi, tiny Euphorbia herbs and Hibiscus shrubs, Grandidier's mongoose, lemur species, tortoise species, and birds such as the red-shouldered vanga.

Environmental Protection. The government of Madagascar has responded to environmental pressure by designating protected areas (covering over 1 million hectares by 2000) and marine national parks, by trying to develop sustainable levels of forest exploitation and by encouraging alternatives to slash-and-burn agriculture, by teaching about overpopulation and environmental degradation at school, and by trying to control population growth and migration.

However, paralyzed by social and political instability and by financial constraints, the government has relinquished responsibility for protected zones to international agencies, environmental groups, and the private sector. These include the World Wildlife Fund (WWF), the Lemur Conservation Foundation, Primate Conservation Inc., the Madagascar Fauna Group, the Wildlife Trust, Conservation International, the Missouri Botanical Garden, the Wildlife Conservation Society, and the U.S. Peace Corps.

In addition, a 1990 World Bank program increased the planting of pine and eucalyptus to satisfy fuel needs. Notable individuals involved in conservation efforts include Henri and Jean de Heaulme, the 1985 Getty Prize Winners for work in preserving Madagascar's wildlife, and Dr. Pat Wright of the State University of New York, whose work in helping to establish the Ranomafana National Park and initiate sustainable agricultural practices among small farmers gained her a MacArthur "genius" grant and a knighthood from the government of Madagascar.

In developing conservation programs, all agencies attempt to involve the local community. Thus in 1990, the World Wildlife Fund brokered a $4.5-million debt- for-nature exchange scheme to help Madagascar's Department of Waters and Forests protect the island's forests, initiate reforestation programs, and train over four hundred local conservation agents. Alongside UNESCO (United Nations Educational, Scientific, and Cultural Organization) and the Kew Botanical Gardens (London), the WWF promotes research into traditional plant remedies and the sustainable harvesting of valuable plants.

In addition, it and other conservation organizations help to preserve habitats, establish reserves of native plants and animals in captivity outside the country, and reintroduce such species to native protected habitats. Both commercial and nonprofit organizations have also initiated ecotourism, designed to compensate for potential revenue lost when commercial exploitation of areas is forbidden and to pay for the required tourist infrastructure and park management.

Poverty and the Environment. Poverty is a major force behind peasant destruction of forest: Madagascar is one of the world's poorest countries, with an annual gross national product (GNP) of $4 billion in 1999 and over 70 percent of its population below the poverty line. Foreign debt (which stood at $3.3 billion in 2001) represented 105 percent of GNP in 1998.

The situation has been aggravated by International Monetary Fund and World Bank austerity measures imposed from the mid-1980s and by natural disasters, notably drought and cyclones. For instance, in early 1994 Geralda, the worst cyclone to hit Madagascar since 1927, left 500,000 homeless and severely affected agriculture and infrastructure, especially on the northeast coast, causing an estimated $45 million of damage.

In the early 1980s, the debate over the conflict between human and conservation needs resulted in a recognition that conservation cannot be separated from the human condition. Only timely, well-funded, and competently managed external aid can hope to quickly alleviate poverty and thus remove the major impediment to conserving Madagascar's unique flora and fauna.