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The End of Eden?

Madagascar's forests¿home to thousands of species found nowhere else¿are disappearing at an alarming rate
aging



J. W. Stewart
Gray Bamboo Lemur
Image: KATE WONG

GRAY BAMBOO LEMUR

In the cool mist of morning, the Analamazoatra rain forest is surprisingly quiet. My guide stops to point out a leaf-tailed gecko blending almost imperceptibly into the bark of the tree it is hugging. Seconds later he calls my attention to the quinine plant, known for its antimalarial effects. A blue-feathered bird flits by, and we press on in silence. Then out of nowhere, an eerie wail floats through the trees, an utterance unlike any I have ever heard. It is the call of the Indri, the largest of Madagascar¿s unique primates, the lemurs. A chorus ensues as Indris from up to several kilometers away reply, reminding each other of territory boundaries. They are the lucky ones. As residents of a well-managed national park, these lemurs enjoy a protected habitat, and Malagasy culture forbids the killing of their kind. Elsewhere in Madagascar¿s forests, however, trespassing abounds. The perpetrators are not rogue lemurs. Rather they are people, destroying the country¿s forests at a staggering rate.

Uroplatus ebenaui
Image: KATE WONG

LEAF-TAILED GECKO

Habitat destruction on Madagascar is particularly devastating because it houses such high levels of biodiversity. Moreover, the vast majority of its plants and animals are endemic¿that is, they are found no place else on Earth. Indeed, according to a report published last February in the journal Nature, 9,704 of the country¿s 12,000 plant species are endemic; of its 987 vertebrate species, 771 are likewise unique, with new species continuing to come to light.

Brown lemur
Image: KATE WONG

BROWN LEMUR

Such figures are extraordinary considering that Madagascar is a small nation roughly the size of Texas. The island¿s myriad unique organisms are the result of its biogeographic history. Once it formed part of the giant supercontinent known as Gondwana, flanked by Africa and Australia. But millions of years ago the continents began to shift, and Madagascar drifted out to sea toward its present-day location in the Indian Ocean, some 250 miles off the eastern coast of Africa. Thus, for more than 160 million years it has been separated from other landmasses, a divorce that has enabled its plants and animals to evolve in isolation. The result is an unsurpassed density of plants and animals that are endemic not only at the species level but in many cases also in the broader scientific categories of genus and family.

Chamaeleo brevicornis
Image: KATE WONG

CHAMELEON (Chamaeleo brevicornis)

Madagascar¿s wealth of biodiversity contrasts greatly with the poverty of its people. With a per capita income of around 300 dollars a year, it is one of the poorest nations in the world. It also has one of the highest population growth rates¿3.1 percent annually. Consequently, human pressures have increasingly taken their toll on the country¿s natural resources. Indeed, in the 2,000 years since humans first arrived, intact forests on the island, which is believed to have once been almost entirely forested, have dwindled to a mere 5 percent of their original extent¿a level of destruction that is among the highest on the planet.

Ringtailed lemur
Image: KATE WONG

RINGTAILED LEMUR

One especially destructive practice is the annual burning of grass and brush in the west and in the central highlands of the island, where people raise cattle. They burn in the dry season so that they¿ll have a better regrowth of grasses when the rains come again, explains Ronald Nussbaum of the University of Michigan. Burning that grass is not in and of itself problematic because the grasses in these regions have largely been introduced. The problem is that these fires get away from

fire
Image: KATE WONG

BRUSH FIRE

them and burn up to the edges of the forest. Though they usually burn themselves out soon thereafter, he says, "you¿re losing about 10 meters or 20 meters of peripheral forest around every reserve every year." (Ironically, the cattle are not really used for milk or meat. Instead they serve primarily as indicators of prestige.) "You can see their logic on a short-term basis, but on a long-term basis it¿s a losing strategy," Nussbaum warns. Continued burning will consume the forests that protect their water sources and exacerbate the already serious erosion problem, he says. "Eventually the burning regime is clearly going to be a major factor in the destruction of the entire environment."

No one is more painfully aware of Madagascar's plight than the biologists who work there, Nussbaum among them. Over the past decade he and his colleagues have discovered more than 150 new species of amphibians and reptiles in Madagascar, in addition to the 400 that were already known.

Chamaeleo parsoni
Image: KATE WONG

CHAMELEON (Chamaeleo parsoni)

But the discoveries are somewhat bittersweet. "Simple logic tells us that over the last 30 to 50 years there have probably been hundreds of amphibian and reptile species that have been wiped out," Nussbaum rues. "They¿re just blinking out when the forest blinks out on us."

Dyscophus antongili
Image: KATE WONG

TOMATO FROG (Dyscophus antongili

New species of primates continue to emerge as well. A paper in the October 10 issue of the Proceedings of the National Academy of Sciences describes newly recognized species of mouse lemurs, the most diminutive primates. They are also the subject of a paper in the October issue of the International Journal of Primatology. But for these creatures, too, the bad news overshadows the good. In a paper currently in review at the journal Oryx Hamburg University zoologist J¿rg Ganzhorn and his colleagues report that at least three of Madagascar¿s unique ecosystems have sustained so much damage that many of the resident large animal species, including a number of lemurs, have disappeared from them. Furthermore, the researchers suspect that even if habitat destruction were to halt in these areas, the remaining large animal species would have little chance of maintaining viable populations beyond the next few decades. Ganzhorn is particularly worried about smaller, high-risk regions such as the coastal forests and the dry deciduous forests in the west, which he notes tend not to receive the attention of conservation organizations who want to maximize their chances of having success stories to bring back to their donors. Too often such areas are overlooked in favor of the more "fashionable" rain forests.

Radiated Tortoise
Image: KATE WONG

RADIATED TORTOISE

Ruffed lemur
Image: KATE WONG

BLACK AND WHITE RUFFED LEMUR

Madagascar's abysmal situation is not for lack of trying among conservationists. The international community has been funding conservation efforts in Madagascar since 1985, says Russell Mittermeier, president of Conservation International. But "the commitment of the government leaves a bit to be desired," he says. Problematically, although the government has established a number of reserves around the country, "there¿s only a relatively small number of existing protected areas that are getting the full-scale management that they need to be effective over the long term," Mittermeier observes. "What you see happening at reserves is not what one expects," Nussbaum says. "You see people cutting trees, you see people burning down the edge of the forest so they can clear land to plant crops or raise cattle. Although these reserves are supposed to be left alone, it¿s not being enforced."

Charcoal
Image: KATE WONG

CHARCOAL FOR SALE

In a country where people have to worry about where their next meal is coming from, contemplating conservation is a luxury. "They need wood to build houses and for fires, and charcoal to cook their food. They need land cleared so they can raise more cattle and raise more crops. That¿s how they survive," Nussbaum points out. Ganzhorn agrees. You can¿t just tell these people not to use the wood, he insists¿you have to give them alternatives.

Sifaka verreauxi
Image: KATE WONG

VERREAUX'S SIFAKA

Yet even in cases where workers have provided alternatives, conservation efforts have still floundered. "Sometimes what¿s been lacking is a clear message to the local people about why [the international community is] working with them," Mittermeier remarks. "If we¿re helping them improve their lifestyle they¿ve got to understand that it¿s also because we¿re interested in maintaining this ecosystem and that there is a responsibility on their part to respect the legislation in place and not continue to destroy the forest." In a number of cases, there has not been enough emphasis on that, he observes, thus "the objectives of the conservation and development program may not have been sufficiently realized because the messages to the local people were not entirely clear. They didn¿t really understand why it was that we were there in the first place."

Educating children and students at the college level is of utmost importance, Mittermeier says. Just as kids in the U.S. are exposed to issues concerning habitat preservation, children in Madagascar should be as well. And college students with an interest in conservation should be provided with seed money for projects. Education efforts should be aimed at developing a cadre of future conservationists in Madagascar, he says.

A sea change in the way the government handles conservation is likewise critical. Continued failure of Madagascar¿s decision makers to enforce the protection of these reserves may do an added disservice to its people by losing foreign aid. "Madagascar gets significant resources from the international community beyond what would go into another comparably poor country because of its biodiversity," Mittermeier says. "I don¿t think they fully recognize how critical that is and how much of a role it¿s played in bringing resources in." In the end, then, the decision rests with the people of Madagascar. As I sit in my New York office sorting through snapshots of marvelous animals and plants, I remember the haunting cry of the Indri and hope that they make the right choice.

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