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 Madagascar and other IslandsThe Biological Wealth of an Impoverished Country: Reptiles and Amphibians: Page 1 Of these native reptiles and amphibians, at least 19 are known to be threatened with extinction. A preliminary list includes 17 species of reptiles (four tortoises, a freshwater turtle, four sea turtles, a gecko, four chameleons and three boa snakes) and two amphibians, both frogs. All are in higher categories of threat: Endangered or Vulnerable by the 2000 IUCN Red List of Threatened Species (Hilton-Taylor 2000). All but the sea turtles are endemic to Madagascar.
The arid regions at the northern and southern ends of Madagascar are home to two intricately patterned tortoises, both in danger of extinction. In the north is a species considered by many to be the world's most endangered tortoise: the 18-inch Madagascar or Plowshare Tortoise (Geochelone yniphora), whose tan, domed shell is marked with narrow black lines in delicate hexagonal patterns. The Plowshare name came about because of a protuberance on the tortoise’s lower shell that turns up, a kind of knob that remotely resembles a plowshare. This knob is used by males in sparring contests. From the 17th century onward, thousands of these tortoises, which were once abundant and widespread, were shipped every year to the nearby Comoro Islands to use as meat for settlers, driving the species to the edge of extinction before the trade finally ended in the 19th century (Juvic et al. 1981). Their populations never recovered, due to the continued take by villagers for pets and the massive destruction of their habitat. Known to the Malagasy as the "Angonoka," this tortoise was headed for extinction until 1985 when the Jersey Wildlife Preservation Trust was requested by the IUCN to work with the Malagasy government in formulating a rescue plan, Project Angonoka (Reid 1995). Research on the tortoise’s wild status and behavior began immediately, and a captive-breeding program was established at a government forestry station (Reid 1995).
By 1986, eight adult tortoises had been gathered from the wild and placed in an enclosure which had ample vegetation and conditions natural enough that two male Angonokas immediately began their fights of strength (Reid 1995). Gerald Durrell, founder of the Jersey Wildlife Preservation Trust, in his book, The Aye-aye and I (1993), described lone males showing no interest in breeding, even if surrounded by females. But when another male is present, they face each other prepared for combat: "The two males, rotund as Tweedledum and Tweedledee dressed for battle, approach each other at what, for a tortoise, is a smart trot. The shells clash together, and then the plowshare comes into use. Each male struggles to get this projection beneath his opponent and overturn him to win a victory in this bloodless duel" (Durrell 1993). Finally, when one is able to overturn his opponent, he lumbers over to mate with the female while the vanquished male "wanders dispiritedly away" (Durrell 1993).
Project Angonoka has shown success both in captive breeding these tortoises, which may number only between 300 and 1,000 in the wild, and in working with local people to conserve remaining wild populations (Durbin et al. 1996). In fact, by 1995, a total of 140 captive-bred juveniles, ranging in age from 10 months to 6 years, had been produced at the breeding center. The breeding program was described in an illustrated article entitled "Observations on Hatchling and Juvenile Captive-bred Angonoka in Madagascar," published in the Jersey Wildlife Preservation Trust's annual journal, The Dodo, issued early in 1996. Within months, the captive-breeding program was devastated by the theft of 76 animals--two adult females and 74 hatchlings. On May 6, 1996, someone cut through the flimsy chain-link fence and the wire of the enclosure and took half the animals that were the fruit of a decade's work. Not until a female is 20 years old does she begin breeding, so the loss of two breeding females and their hatchlings dealt the program a devastating setback (McNeil 1996a). The burglary may have been an inside job, since the dog on the premises did not bark to alert the personnel who were sleeping close by (Tyson 2000). It is unlikely that these adult females will breed in captivity, as there are almost no adult male Plowshare Tortoises in breeding programs, and without more than one, no breeding occurs.
Animal smugglers care little about the effect of their actions on the survival of endangered species. Reptile collectors will pay thousands of dollars for rare specimens, and this break-in had been planned. A Dutch rare animal dealer had advertised Plowshare hatchlings for sale the month before, at $3,000 apiece, saying they would be "available soon" (McNeil 1996a). Ten of the hatchlings were traced to Prague, where wildlife law enforcement is weak, and others were suspected to be in the Netherlands, where they would be sold to collectors in the United States, Spain, Germany and Japan (McNeil 1996a). The loss of these tortoises cost the breeding program years of work. Don Reid, the Conservation Field Officer in charge of the Plowshare Tortoise captive-breeding program, had experimented for years to achieve a proper diet for the tortoises, arranged male combats, and conducted lengthy experiments to learn proper conditions for the eggs to hatch (Reid 1995). These tortoises became so tame that they would stretch their necks out to be scratched (McNeil 1996a). Although discouraged by the theft, he continued the breeding program; 40 new tortoise hatchlings were produced in late 1996, bringing the total to 130 juveniles. In 1998, several of the smuggled tortoises were seized from a Malaysian animal dealer in Mexico City who had been the subject of a long-term U.S. Fish and Wildlife Service undercover investigation. The same year, three more Plowshare Tortoises were seized in Belgium as they were being imported (TRAFFIC 1999a). The species is listed by the 2000 IUCN Red List of Threatened Species as Vulnerable, and is protected by the Malagasy government, which bans trade.
Officials from the Jersey Wildlife Preservation Trust and other conservationists have sponsored education programs aimed at informing local people about the tortoises and their rarity. This has resulted in their cooperation in helping to guard wild tortoises from poachers and control brush fires (Durbin et al. 1996). This region in northwestern Madagascar has lost most of its forest cover; Arab residents cut trees and burn them to clear the land for agriculture, and feral pigs kill the young wild tortoises (Durbin et al. 1996). So much clearance of natural vegetation has taken place that the climate has become increasingly more arid, causing ponds to dry up. Tree cutters are now turning to the mangroves, causing siltation of the inlets, which affects prawn harvests (Durbin et al. 1996) and destroys a key aquatic environment on the island.
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