Farmers call them pests. Scientists want their kidneys. Hunters trap and shoot them, and tourists hope to see them leaping from trees.

　　There are 14,000 green monkeys living on the tropical Caribbean island of Barbados - one for every 20 people - and they are sought after for reasons ranging from a bounty on their tails to their use in polio vaccines.

　　Historians believe the monkeys arrived on slave ships from West Africa in the 17th century - either as pets or as food. Today, islanders have a love-hate relationship with the small primates, with many calling them a nuisance better off dead.

　　A dozen or so hunters work under the government's bounty program, which pays US.50 for each monkey killed.

　　To earn the government bounty, hunters are required to bring in 7.6 centimeters of the monkey's tail.

　　They usually cut the end of the tail and leave the carcass behind.

　　"A week never passed that we wouldn't catch monkeys," said Emerson Benskin, 33, who quit monkey-trapping after he found work on a farm.

　　The barbados Primate Research Center pays US for monkeys unharmed, arguing the 1,500 brought in alive every year make good research subjects.

　　Sometimes, though, the center takes their kidneys to make polio vaccines.

　　That has angered animal rights groups but turned the centersintosa major source of the vaccine - with about 70 percent of the world's supply coming from its monkeys.

　　The center sells about 800 monkeys each year to various companies and other research centers, for US,500 each, said Jean Baulu, a Canadian primatologist and owner of the center.

　　Baulu said scientists use the monkeys' kidney cells because they reproduce several times without mutating. That means one pair of kidneys from green monkeys can produce many more vaccine doses than cells from other animals.

　　"My idea is not to reduce the monkey population, but to keep it stable," he said. "Since 1988, polio dropped by 95 percent in the world."

　　Years ago, the research center and Barbados were blacklisted by animal-rights activists who hung posters around London, urging people to boycott the former British colony.

　　The campaign did little to drive away tourists - Barbados is a popular vacation spot for Europeans. Activists still protest the center.

　　"There is absolutely no excuse for taking these animals from the wild and torturing them," said Peter Wood of the Norfolk, Virginia-based People for the Ethical Treatment of Animals.

　　Money can also be made from selling monkey babies as pets - US each - or convincing tourists to be photographed with a monkey or two.

　　The monkeys generally grow to about 60 centimeters tall and live in troops of about 15. They have no natural predators on the island.