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 Madagascar and other IslandsThe Biological Wealth of an Impoverished Country: Reptiles and Amphibians: Page 3 Madagascar is home to two‑thirds of the world's chameleons--at least 62 species--more than any other country (Tyson 2000). Among the island's endemic chameleons are the world's smallest and largest species. The smallest, Brookesia minima, is only 1.3 inches long, while the largest, Furcifer oustaleti, measures 27 inches in length (Preston‑Mafham 1991). Their conical eyes, moving independently, can look forward and backward at the same time, swiveling almost 180 degrees in either direction (Preston-Mafham 1991). This adaptation, processing totally divergent information spontaneously, would confuse most vertebrates, but chameleons, even very young ones, are adept at using these dual periscopes to locate insects and other prey. They hold onto the thinnest branch with their prehensile tails, and with long, thin legs bent at the knees, they walk in an odd back-and-forth swaying motion that resembles leaves moving in the wind. Their chunky bodies and spindly legs give them an awkward appearance, but they are superbly adapted to catching their prey by unfurling a long, sticky tongue--curled upside their mouth--with lightning speed, nailing an unaware insect with astonishing accuracy.
Their camouflage coloration, which varies greatly from bright greens, mottled browns, reds and blues, helps protect them from avian and mammal predators. Contrary to general opinion, chameleons do not change colors as they move about in the trees or on the ground to match their background. When they suddenly change colors, it is as a territorial or sexual display meant for other chameleons (Preston-Mafham 1991). Some species have horns and other protuberances, giving them the appearance of miniature dinosaurs. A few species show sexual dimorphism, or a physical difference between the sexes. The contrast can be so striking that some were considered separate species when first identified (Burger and Price 1996). In one species, for example, the female is black and yellow, and the male a mottled brown and white (Burger and Price 1996).
Chameleons are heavily exploited by collectors who capture them for sale in pet stores around the world, threatening them. Collectors will pay $1,000 or more per animal for rare species. This trade, which involves thousands of individuals, has caused declines in many species. The Malagasy government has banned trade in most species, but enforcement is not strong. One chameleon, Chamaeleo brevicornis, of which 795 were exported in the first six months of 1990, is restricted to only a few areas of primary forest (Behra 1993). An ongoing study will evaluate whether to allow trade in the commoner species. Chameleons captured and shipped abroad for the pet trade suffer very high mortality as a result of inhumane transport conditions and inadequate care in pet stores and people's homes. They require special conditions of temperature and humidity, and many have specialized diets. In short, they are not suited to being house pets. In the care of specialists, they can be kept alive, but most captive breeding has been unsuccessful. Some of the rarer species, such as the beautiful blue-green Parson's Chameleon (Chamaeleo parsonii), which can reach lengths of more than 20 inches, have not been bred to the second generation, and mortality is high. All chameleons are on Appendix II of CITES, which requires export permits, but none has been listed on Appendix I of CITES, which would ban commercial trade.
Although some chameleons have adapted to disturbed habitats, such as weedy fields and shrub landscape, the majority favor natural habitats. The small Brookesia chameleons, of which one species is listed by IUCN as Vulnerable (Hilton-Taylor 2000), require undisturbed, primary old-growth forest. Three other chameleons, all Furcifer genus, are listed as Vulnerable by IUCN. All are in decline, approaching endangered status.
Although many Malagasy regard chameleons as ugly porters of bad luck (Burger and Price 1996), for tourists, they are the second most popular animals, after lemurs. Some Malagasy, aware of the fascination with which chameleons are held by tourists, capture them and offer them for viewing or sale.
Another lizard being captured for the pet trade is the extraordinary 4-inch-long Leaf‑tailed Gecko, Uroplatus fimbriatus, a true master of camouflage. Resting during the day with its head tight against a tree trunk, an elaborate lacy fringe along the underside of the body allows it to melt into the tree, while its skin is patterned to resemble tree bark. Even its golden eyes are streaked with tiny dark lines that imitate bark. With broad, flattened front feet splayed out against the bark and hind legs held vertically under a spatula‑like tail, it becomes virtually invisible (Preston‑Mafham 1991). If discovered, however, it has a defense. Opening its mouth wide to reveal a crimson‑red tongue, it raises its tail vertically and emits an ear-splitting screech, no doubt intended to be a fearsome display (Preston‑Mafham 1991, Tyson 1994). Malagasy boys have discovered the haunts of the Leaf-tailed Geckos, and capture hundreds--thousands by their accounting--for sale to foreign middlemen who pay them less than $1. They are sold in the United States for $250 a pair (Tyson 1994, Tyson 2000). On Nosy Be island off the northern coast, schoolboys claim to have captured 40,000 over the past six years (Tyson 2000). A threatened gecko, Standing's Day Gecko (Phelsuma standingi), is native to the spiny forests of the south and is one of the most coveted by collectors (Tyson 2000). It is hunted out of many areas because Malagasy have captured hundreds, receiving $1.20 per gecko, while reporting only a few to authorities (Tyson 2000). It is on CITES Appendix II, and sells in the United States for $80 to $200 apiece (Tyson 2000). Most species of geckos bring the village collectors only about 3 U.S. cents, while the exporter receives $9 to $13 and U.S. retailers get $75 or more (Burger and Price 1996). In most cases, these pet reptiles live a very short time, and represent a mere toy to the consumer.
The export trade in live lizards involves an enormous number of animals. One gecko, Phelsuma serraticauda, was known only from a few museum specimens until 1,360 specimens were chronicled as exported during the first six months of 1990 for the pet trade (Behra 1993). During this same period, 22,837 lizards--geckos, Phelsuma genus, and chameleons, Chamaeleo genus--were exported from Madagascar (Behra 1993). Between 1986 and 1991, almost 145,000 lizards of 17 species were exported; of these at least 38,325 were chameleons of 21 species (Burger and Price 1996). Many of these are species that are endemic to restricted areas, or threatened in the wild. The U.S. Fish and Wildlife Service’s “Operation Chameleon” succeeded in arresting 19 people in 1998, among whom was a major Malaysian smuggler and an American, Tommy Crutchfield, who was arrested at Miami International Airport with suitcases full of rare snakes, tortoises and lizards. In another case, a Canadian and a Dutchman were arrested at Chiang Kai-shek International Airport in Taiwan with numerous chameleons and geckos, including some threatened Standing's Day Geckos.
Several gecko species have extremely limited ranges. A newly described leaf gecko, Uroplatus malama, is known from a single specimen taken in a remnant of lowland rainforest in southeastern Madagascar (Burger and Price 1996). Only two specimens of a closely related species, Uroplatus malahelo, exist, native to a small patch of forest in the south (Burger and Price 1996). When discovered, its habitat was being logged, and the species may already be extinct (Burger and Price 1996). An extremely rare lizard, Zonosaurus boettgeri, known from two specimens that were taken in the 1890s and subsequently disappeared, has been rediscovered on the island of Nosy Be by herpetologist Chris Raxworthy and volunteers from Earthwatch Institute (Tyson 2000). The two individual lizards were killed as specimens upon rediscovery (Tyson 2000).
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