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 Madagascar and other IslandsThe Biological Wealth of an Impoverished Country: Mammals: Page 2 Far better known to the world, the lemurs are the focus of many programs to conserve them, as well as research on their wild behavior and biology. New species continue to be discovered; most recently in 2000, three new species of tiny mouse lemurs. Three more have been rediscovered, an indication that other species may yet be discovered to add to the present total of 33 species (Garbutt 1999). This is the only country with five families of primates, making up more than one-third of all primate families; it is home to 12 percent of all primate species and 21 percent of all primate genera (Mittermeier et al. 1999). Unlike Brazil, however, which is another center for endemic mammals, Madagascar is far smaller, the size of Kenya, covering 226,656 square miles, or 0.4 percent of Earth's surface (NYT 2000). The number of lemur species is not an indication of their variety since many subspecies differ so radically from one another that in the future, each may be accorded full species status. One species of sifaka, a long-legged kind of lemur, has one subspecies that is pitch black, and another that is pure white. At least 51 species and subspecies of lemurs are known to exist (Mittermeier et al. 1999).
The most gregarious of the lemurs are the Ring‑tailed Lemurs (Lemur catta), who travel about in boisterous, friendly troops, living mainly on the ground. These lemurs have long, fox-like muzzles, large, soft golden-brown eyes, fluffy, gray fur, and black-and-white striped tails. Their body length is 15 to 17 inches, but their rope-like tails are half-again as long, from 21 to 24 inches (Nowak 1999). These 5-pound primates use their boldly patterned tails in a complex language of mutual visual and scent signals. They wave them about to show dominance, as a signal to follow other group members, or rub them on their wrist glands to wave at their rivals in territorial battles (Sleeper 1997). Moving about in troops of up to 25 individuals, they walk rapidly on the ground with the tail held high, waving it about. They wrap their tails around themselves for warmth on chilly nights. Extremely affectionate and playful, their core group is dominated by females (Jolly 1988).
In reserves where they are strictly protected, Ring-tailed Lemurs become very tame, napping on the ground in piles of leaves near tourists. Sometimes they sprawl out on their backs with arms spread wide apart. Females usually have a single young, but when twins are born, one may be "adopted" by a non-pregnant female, who may begin to produce milk in response to her surrogate role (Preston-Mafham 1991). Aunts also help in raising the young, and the daughter born the previous year babysits (Jolly 1988). Lemur babies are a source of great interest to the entire troop, females gathering around the mother and her young, grooming one another and the babies, forming a "grooming pod" (Preston-Mafham 1991). Only half of the infants survive their first year, and only 30 percent reach adulthood (Garbutt 1999). "A Lemur's Tale," shown on PBS in 1996, is a touching film about the death of a young Ring-tailed Lemur. Some fall from high branches, are killed by small carnivores or hawks, die of undiagnosed illness or starve in years of drought in their arid habitat. Ring-tailed Lemurs communicate with one another in a variety of sounds, from soft mewing contact calls to a territorial "bark-howl." Sometimes chasing and cuffing other members of their group, they are mainly peaceful, spending many hours a day in mutual grooming and in "snoozing-huddles," in which several animals form a complicated embrace from which tails and feet stick out in all directions (Preston-Mafham 1991).
In recent years, Ring‑tailed Lemurs have been classified "high priority" for conservation by the IUCN and the Species Survival Commission (SSC) Primate Specialist Group because their habitat of dry woodlands in southern Madagascar is disappearing at an alarming rate due to fires, overgrazing by livestock and tree cutting; they are also hunted with dogs in some areas, and captured as pets (Mittermeier et al. 1992, Garbutt 1999). Their distribution has become increasingly patchy as forests are cut (Garbutt 1999). The 2000 IUCN Red List of Threatened Species lists the Ring-tailed Lemur as Vulnerable, or declining toward endangered status.
One of the strangest mammals in the world is the Aye‑aye (Daubentonia madagascariensis), so unique that it is assigned to its own family, Daubentoniidae. When first discovered, scientists classified it as a squirrel because of its long, bushy tail and short‑legged body. In 1863, however, after anatomical studies, the Aye‑aye was revealed to be a lemur, in spite of incisor teeth that never stop growing, long, clawed fingers and other unlemur‑like characteristics. Aye-ayes have a perpetually startled expression: huge, round protruding eyes dominate the face, the pupils completely surrounded by deep golden irises. Dark rings surround their eyes, heightening the eerie appearance. The rest of the face and body are gray to black, with long grizzled guard hairs. Spending the day in their twig and leaf nests, Aye-ayes emerge at night to forage for insects and fruit (Garbutt 1999). The Aye-aye's enormous ears are sensitive to the movements of insects under tree bark. At Duke University Primate Center, which has the world's largest number of captive lemurs, Aye‑ayes have been filmed using their middle finger, which is twice the length of the other fingers, and skeletally thin, to tap on wood, listening for the movement of insects under the bark. When presented with a block of wood containing insect larvae in holes, the Aye‑aye taps the wood and, cocking its head, can tell, even in the case of a hidden hole, the location of the insects, which it then extracts almost surgically, with its middle finger. This primate fills the ecological role of a woodpecker. Aye‑ayes eat fruit as well, biting holes into the hard shells of coconuts and scraping the meat out with their middle fingers (Petter 1965). They have also been seen eating nuts of a native tree, nectar from the Traveller's Tree, fungus and lychee nuts (Garbutt 1999).
Aye-ayes have been heavily persecuted by the Malagasy, who consider them to be the embodiment of evil. In general, they are killed whenever seen. Dr. Ian Tattersall once found a dead Aye‑aye with a wire pulled tight around its neck (McNulty 1975). In 1990, apparently to dispel the bad luck caused by its having entered a village, local people set an Aye‑aye tail on a pole next to the road (Simons 1993). At one time, Aye-ayes were considered among the most endangered animals in the world, facing imminent extinction. To prevent their extinction, a few were captured and released on Nosy Mangabe, a small islet off the northeast coast. Fortunately, Aye‑ayes survived on the main island, perhaps because coconut plantations provided food when their forests were cut. Feeding at night, they remained undetected until recently. The Malagasy continue to persecute them.
Since the early 1980s, field surveys have revealed that Aye-ayes have a larger distribution than was originally thought. In 1991, they were seen for the first time in western Madagascar in the northern mountains (Simons 1993). With confirmed sightings in many eastern and northern forests and a few western localities, Aye-ayes inhabit a variety of forest types (Garbutt 1999). They can survive in secondary forest, coming out of their stick nests only at night. And while once thought solitary, groups of three to four individuals have been seen traveling together and feeding at foraging sites (Garbutt 1999). In spite of the greater distribution, the Aye-aye is an endangered species and almost certainly is declining (Garbutt 1999). Aye-ayes require large tracts of forest to maintain viable populations and to protect them from the persecution that often results in their deaths (Garbutt 1999). Although very rare in captivity, several captive births have occurred in recent years at the Duke University Primate Center and Jersey Wildlife Preservation Society zoo in England.
One lemur has recently been rediscovered in the wild and, in the process, an entirely new species was found. The Greater Bamboo Lemur (Hapalemur simus) seemed to have disappeared in the wild some time in the mid-19th century. Not until 1964 was this 5-pound, grizzled, gray-olive lemur seen again in a village market, where it was purchased by a French scientist. Unfortunately, it escaped. A pair captured in 1972 in a southeastern rainforest lived in the zoo in Madagascar's capital city, Antananarivo, until both male and female and their two offspring died (Quammen 1996).
Patricia Wright, an American primatologist, decided to search for this species in 1986 in its supposed range. Fossil evidence indicates that 1,000 years ago, the Greater Bamboo Lemur was widely distributed throughout most of Madagascar's forests, and European naturalists saw it fairly regularly in the 19th century. When she saw a russet-colored lemur clinging to a trunk, making loud "tonking" calls, Wright assumed that she had rediscovered the Greater Bamboo Lemur. Although a different color, she concluded that these animals probably represented a color variation (Quammen 1996). A German primatologist, Bernhard Meier, made independent studies in this patch of rainforest at the same time, also discovering the reddish-gold lemur. Both scientists had great difficulty making observations because of its extreme shyness (Quammen 1996). Finally one was caught, and in 1987, after chromosomal and anatomical studies were done in France, this lemur was found to be an entirely new species (Jolly 1988). It was named the Golden Bamboo Lemur (Hapalemur aureus) in a joint zoological paper by Meier, Wright and three other biologists (Preston-Mafham 1991). After months of unsuccessful attempts, Wright took the first photographs of the Golden Bamboo Lemur in the wild. Its beautiful golden-red face mask and belly contrast with darker brown fur on the rest of its body. (See color photographs in Garbutt 1999, Jolly 1988 and Preston-Mafham 1991). This lemur has been found at another location further north, and it is not known whether these populations are isolated from one another. Its population is apparently very low, as only about 1,000 animals have been estimated in the original location of discovery, and its habitat continues to be cleared (Garbutt 1999). The 2000 IUCN Red List of Threatened Species has classified the Golden Bamboo Lemur as Critical, the most endangered category. Its limited range places it in great jeopardy, and it has been hunted with slingshots; its long-term survival is not secure (Garbutt 1999).
The Greater Bamboo Lemur, the animal first sought, was later found in the same forest, resembling original descriptions and clearly a separate species from the Golden Bamboo Lemur; a third species of bamboo lemur, the Gray Bamboo Lemur (Hapalemur griseus), weighs only 2 pounds. It has smoky gray fur and golden eyes, and lives alongside the latter two species in this same forest. This lemur lives in other parts of Madagascar as well (Preston-Mafham 1991).
Each of these three bamboo lemurs eats different parts or species of bamboo plants. One eats the leaves, another the pith, and the third confines itself to new shoots, leaf bases and pith from narrow stems (Quammen 1996). Amazingly, chemical analyses of the plants eaten by the Golden Bamboo Lemur found them to have high concentrations of cyanide, a chemical usually toxic to mammals. Golden Bamboo Lemurs weigh only about 2.2 pounds, and Wright and her co-workers found that, based on toxicity tests of other mammals, they eat 12 times the amount of cyanide that should kill them (Quammen 1996). This is another example of the biological mysteries of Madagascan wildlife.
The Ranomafana forest, with its rare and endemic lemurs and other unusual fauna and flora, would likely have been cut by the Malagasy for more farmland, but Wright spent five years in a successful effort to protect it in the newly‑created Ranomafana National Park (Bohlen 1993, Mittermeier et al. 1992). This new park covers 108,000 acres of old-growth eastern lowland rainforest. Giant rosewood and other ancient trees tower above a lush understory. It is an extremely important--perhaps the most important--forest for lemurs. Fourteen species of lemurs and 18 other endemic species of mammals live in the park (Jolly 1988). Local people cooperated fully in setting the park’s boundaries, aware of the importance of saving forests. They had experienced a major catastrophe when a cyclone caused landslides, burying entire families in their homes, all precipitated by deforestation (Jolly 1988). In spite of these remarkable achievements, some tree cutting still occurs in Ranomafana National Park (Garbutt 1999).
Wright has continued to study lemurs, now specializing in the exquisite Diademed Sifaka (Propithecus diadema) (Brody 1998). Sifakas are the most acrobatic lemurs, leaping from tree to tree, but they have a unique means of locomotion to cross open spaces between trees. Standing on their long hind legs in an upright posture, they hop sideways, with their arms raised high above their heads. Sifakas can move very quickly in this amazing, dance-like gait, covering distances of more than 100 yards. They are also able to leap vertically to tree branches from a standing position, even carrying babies on their backs. One of their spectacular leaps, some 30 feet up, is the equivalent of a person jumping to the top of a telephone pole. The Golden-crowned or Tattersall's Sifaka (Propithecus tattersalli) is a beautiful, nearly all‑white species with rich yellow-orange on the crown and tinges of this color on its back, legs and chest. Orange eyes contrast with a furless black face. The smallest of the sifakas, it is confined to a tiny area of only about 15 square miles of forest fragments in northeast Madagascar. The Golden-crowned Sifaka's small population of fewer than 8,000 animals, fragmented into isolated populations, is threatened by forest cutting, brush fires, loss of habitat to agriculture and hunting (Garbutt 1999). Distributed in discontinuous patches of forest, these sifakas may become inbred if corridors are not acquired to link populations. A core part of their forest had been scheduled for cutting for charcoal when scientists named these sifakas. The PBS Nature program, “Madagascar. Island of Ghosts,” was the first to film these delicate lemurs (see Video section, Regional - Africa and Indian Ocean Islands). They move about in small groups and feed on a variety of unripe fruits, seeds, shoots, leaves, bark and flowers (Garbutt 1999). No reserve has been set aside for this highly endangered sifaka, although a three-parcel national park covering 20,000 hectares (49,420 acres) has been proposed to protect this species from extinction (Garbutt 1999). The IUCN classifies this species as Critical (Hilton-Taylor 2000).
Although many Malagasy have become far more aware of the need to protect lemurs, some do not understand their rarity or the importance of conserving them. Many rural people still hunt them for food or kill them because of superstitious beliefs. In some areas, the Malagasy try to sell lemurs to foreign scientists. Visiting zoologists studying lemurs have been approached by Malagasy holding captive, and usually injured or dying lemurs, in hopes of a reward. On one occasion, an endangered species of sifaka was brought to primatologist Dr. Alison Jolly, dragged half‑choked by a vine around its neck, with one arm dangling loose below the elbow, a jagged bone protruding; blood oozed down its white fur, and it gasped for air through a muzzle smashed by a flung stone (Jolly 1980). Jolly expressed horror at its condition and refused to pay them any reward. She then amazed them by telling them it was a unique sifaka, found only in that small part of Madagascar. They were incredulous . . . not in Antananarivo? . . . Not in France? . . . Not in America? (Jolly 1980). For the majority of people, lemurs are familiar animals, easy to capture and valuable as food. Malagasy schools, established by the French colonial government, taught them only about European animals, encouraging people to assume that their lemurs were unimportant. Fortunately, many Malagasy are becoming concerned about protecting lemurs, and conservation education is taught in an increasing number of schools.
Some lemurs have bred in captivity in zoos and breeding centers, but most, like the endangered Indri (Indri indri), have never survived in captivity long enough to breed. In their rainforests, they perch high up, clinging to tree trunks to feed, and suddenly leaping vertically to a neighboring tree, pushing off with their extremely muscular, long legs. Panda-like fur of contrasting black and white--black faces and bodies and white arms and legs--gives them a dramatic appearance. Nearly tailless and heavy--but graceful--their eerie songs, sung at dawn and sometimes during the day, form a loud chorus of high-pitched voices that carries for long distances. Indris were once very common in the eastern rainforest, but much of their habitat has been burned away, making them extremely sensitive to the danger of fires. When a 1992 fire threatened a group in a reserve, they raised such a loud cry that the guards were alerted. They rushed to the scene and put out the fire (Rajaonson 1993).
Although originally found in the far north and central highlands, the Indri is now limited to a narrow strip encompassing only half the rainforests on the island (Garbutt 1999). Indris do not reach sexual maturity until between 7 and 9 years of age, and females are thought to give birth only every second or third year (Garbutt 1999). With such a low reproductive rate, they have been very vulnerable to habitat loss and hunting, especially by immigrants (Garbutt 1999). Moving about in small family groups, they are conspicuous to hunters. The Indri is one of the few lemurs whose killing is considered taboo by the Malagasy, but the old taboos are breaking down, resulting in capture and killing. In some cases, religious leaders encourage such killing. A lemur scientist met a Catholic priest who killed several Indris, roasted them and served them to his congregation, as recorded by Faith McNulty in 1975, and this killing has not ceased. In Mammals of Madagascar (Garbutt 1999), two terrified Indris were photographed clinging to poles in a hut, awaiting slaughter for food.
In contrast to the Indri, mouse lemurs (Microcebus spp) are so small that it is hard to think of them as primates. The tiniest is the newly discovered Pygmy Mouse Lemur (Microcebus myoxinus), with an average weight of only 30 grams, or 1.05 ounces, smaller than any other primate (Garbutt 1999). This tiny mammal is 2.73 inches long, with a tail just under 6 inches in length (Garbutt 1999). The other species are slightly larger, with body lengths ranging up to about 5 inches, and tails of equal or greater length (Garbutt 1999). These nocturnal lemurs have huge dark eyes and are agile and active, resembling African bushbabies. They feed on insects, spiders, and even small frogs and lizards, as well as fruit, flowers and nectar (Nowak 1999). Females form groups and sleep in a nest together with up to nine individuals, while males usually nest alone or in pairs; occasionally males are found in a group of females (Nowak 1999).
A key to protecting lemurs and their forest homes is educating the people of Madagascar about them. The Jersey Wildlife Preservation Trust has put up posters with pictures of lemurs and their protected status around the island. Habitat protection is obviously key to conserving lemurs, and another recent development is the protection of the largest remaining area of rainforest in Madagascar. The Masoala Peninsula in the northeast is the sole home of the Red Ruffed Lemur (Varecia variegata rubra), a 9-pound, reddish subspecies of the Ruffed Lemur, but bearing little resemblance to the latter black-and-white species. With $3 million from USAID (United States Agency for International Development) and three years of planning, the new Masoala National Park, covering 210,000 hectares (518,910 acres or 840 square miles), was announced in June 1996 (Terry 1996). This immense park was formally signed into law on October 18, 1997 (Kremen 1998). Thai and Indonesian timber companies had hoped to log these virgin rainforests, but this new law will prevent clearcutting and slash-and-burn agriculture that would have destroyed the forest within less than 50 years. A coalition of organizations helped establish this park, including the Wildlife Conservation Society, CARE and the Peregrine Fund (Garbutt 1999). It will prevent the extinction of the endangered Red Ruffed Lemur, as well as that of the newly rediscovered Madagascar Serpent Eagle (Eutriorchis astur) (see below).
In 1997, five Ruffed Lemurs born and raised in the Duke University Primate Center in North Carolina were released in the Betampona Reserve in the northeast to bolster a small, isolated population of this species (Welch 1997). This reintroduction represented a goal in the captive-breeding program at Duke University, which has long planned such a return of these highly endangered primates to the wild. John Cleese, actor and a member of the 1970s British comedy team, Monty Python's Flying Circus, took an interest in the reintroduction program as an enthusiastic lemur admirer. After contributing to the Ruffed Lemur reintroduction program, he wanted to see how they were faring in the wild, and trekked to their remote release site. A delightful film based on this experience, "Lemurs with John Cleese," was shown on PBS in 1999. These Ruffed Lemurs have been released in an area of dense rainforest and rugged hillsides, a long hike from the nearest road. The biologists and assistants who take part in this reintroduction program show their dedication by living for long periods under extremely primitive conditions. Cleese managed to inject humor into this otherwise arduous situation.
At least six species of lemurs, and perhaps more, serve the ecologically important role of pollinating flowers. Many of Madagascar's plants produce unusually large flowers with strong odors and copious nectars attracting lemurs to feed on them. Should any of these lemurs become extinct, the plants that they pollinate will likely follow. Lemurs also play an important role in dispersing seeds. Research by the German Primate Centre at Hamburg University has found that Brown Lemurs are crucial to the regeneration of the western dry forests. About 10 percent of the island's tree species rely largely or entirely on this species to disperse seeds, which pass through their digestive systems.
The surviving lemurs are in extreme danger of following their relatives into extinction. Conservation organizations accord them extremely high priority among endangered primates, and they are the focus of many programs to preserve them. Twenty-nine of the 33 species are listed in the 2000 IUCN Red List of Threatened Species, all but seven in higher categories of threat. This is an increase of nine species in the four years since the previous edition of the IUCN Red List was published (Baillie and Groombridge 1996). Three species and several more subspecies are in the Critical category of species on the verge of extinction, while seven are Endangered, an increase of four species since 1996. All lemurs are listed on Appendix I of the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES), the category prohibiting commercial trade, and as Endangered on the U.S. Endangered Species Act.
Although lemurs are protected by Madagascan law, hunting is a major cause of mortality. High fines and even jail sentences may be imposed for killing a lemur, but the severity of the penalties might make officials reluctant to enforce the laws (Peterson 1989). Blowguns, snares, traps, sharpened sticks, slings, stones, guns or even clubs are used to kill them (Peterson 1989). To kill small species of nocturnal lemurs, trees are sometimes cut down, and hunters seize them from their nest holes (Peterson 1989). In the late 1980s, a "sport" hunter bragged of killing 12 highly endangered Verreaux's Sifakas in one afternoon (Peterson 1989). In spite of education programs launched in the 1990s urging the Malagasy to protect lemurs, and the rise in tourists who come to see them, which provides revenues, few have benefited from tourism. Hunting remains a major threat (Garbutt 1999). The rise in human population has resulted in an increased demand for food, particularly protein, far more than the ailing agricultural system can supply (Garbutt 1999). The larger lemur species are especially affected. Because laws against killing lemurs are not enforced, much more education is needed about their potential value in attracting tourism and research funds that provide new jobs. Already tourism has raised income levels among some Malagasy, but hunger is still widespread (Tyson 2000).
In the late 1980s, a World Bank official studying the extreme and worsening poverty on the island said that there might come a time when the people of the capital city would scale the walls of the city zoo and eat the lemurs: "On the downward spiral, animals are at the bottom" (Peterson 1989). Such a tragedy is not inconceivable considering that hunger and poverty have deepened in the decade since. Conservation programs must involve communities while providing an incentive to conserve lemurs. Otherwise, it may be impossible to persuade the Malagasy not to slaughter them.
Although the status of lemurs is deteriorating along with their forests, much is being done to prevent their extinction. The past two decades have been of critical importance to lemur conservation. These extraordinary animals are receiving worldwide attention, and habitat protection for some species has been achieved. Not too long ago, their extinctions seemed inevitable and imminent. Conservation education programs, including showing slides of lemurs and other wildlife to rural children, have been launched. Wright helped to finance the building of new schools and the renovation of existing schools near Ranomafana National Park (Tyson 2000). A number of international organizations are integrating lemur and biodiversity studies with the economic development of entire communities (Garbutt 1999).
For a growing number of Malagasy, learning how special their lemurs are has made lemurs a source of pride and an important national treasure. In the future, Malagasy children may learn from an early age about lemurs and want to protect them. A few decades ago, few films had been made of these fascinating primates, while today many films show their habitats, biology and conservation work on their behalf. One is “Spirits of the Forest,” a charming film about many species of lemurs. Others are listed in the Video Section ‑ Mammals. Films of lemurs and the island's environment would provide new insights about these animals if shown to the Malagasy people. Lemurs have also been prominently featured in Madagascar: A Natural History, by Ken Preston-Mafham, a beautiful and informative book, and the first guide book, Mammals of Madagascar, which provides color photos of nearly every species and subspecies, as well as information on habitats, conservation and status (Garbutt 1999).
In some areas of Madagascar, notably on Nosy Be island, lemurs are fully protected by taboo respected by the Malagasy. Here, beautiful Black Lemurs are fed by the villagers and tourists. This island is being developed intensively for tourism, and the strict nature reserve may be made into a national park (Tyson 2000). This will have mixed results, with new income flowing to the local people from park fees--one of the few countries where this occurs--yet with habitat lost and wildlife disturbed as a result of new hotels and a crush of visitors (Tyson 2000).
The gentle, curious gazes and charming behavior of lemurs have left an indelible impression on many people, and their extinction would be tragic, not just for biological reasons, but also because of their unique and delightful qualities.
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