Every two years, an excited crowd of the world's foremost primatologists emerge from distant jungles and lonely labs, and gather together to powwow about the state of their charges. Unfortunately, the news is not always good. Last month, the results of this biennial conversation were published in the 2006-2008 Primates in Peril report, the fourth of its kind, a compilation of the planet's 25 most endangered primate species. "If you took the remaining individuals of these species and gave them a ticket to a football stadium, they would not fill it," says Russell Mittermeier, president of Conservation International and chairman of the World Conservation Union's Primate Specialist Group. "They [number] well under 100,000. It's very sobering."
Primates are being threatened everywhere in the world, but Asia takes the lead this year with 11 endangered species, including the Sumatran orangutan, Siau Island tarsier and Hainan black-crested gibbon. Africa's seven endangered primates include the Cross River gorilla and Miss Waldron's red colobus, which scientists have not spotted since 1993 and fear may already be extinct. Madagascar follows with four endangered species, while South America has three. From Colombia to Southern China, primates are not faring well, and primatologists say their precarious existence is a problem for all of us. Even if we have never set eyes on a Peruvian yellow-tailed woolly monkey before, the species' well-being may affect our own. "Things may not change very much if we lose one more primate species," says Tilo Nadler, director of the Endangered Primate Rescue Center in northern Vietnam. "But where is the limit? ... It is our environment, and primates are part of the biodiversity ecosystem."
In some parts of the world, primates are dinner for big cats. In others, they lend a hand to the local flora by eating plants and dribbling seeds around. Primates are certainly crucial to the global food chain, but as Nadler says, it's hard to know what would happen to the larger environment if a few lemur species on Madagascar died off tomorrow and it's a question that scientists have been working for decades to avoid having to answer. In the last 50 years, only a few primates have been lost to extinction, but some worry the worst is yet to come. "The great fear is that we've been holding back the tide," says Dr. Richard Wrangham, president of the International Primatological Society, one of the report's sponsors. Wrangham says that within the next 20 years, several of the species on the list could be gone.
One major problem is habitat erosion. In Vietnam, for example, which is home to four of the 25 most endangered species, habitat loss as a result of development and persistent hunting for food, medicine and animal skins has reduced the populations of species like the golden-headed langur from thousands of animals in the middle of last century to only 65 today. "The more we look at it, the worse the picture seems to get," says Ben Rawson, a Hanoi-based primatologist with Conservation International (CI), another sponsor of the recent report. Conducting primate surveys in the region, he says, has turned into a process of "documenting the decline of these species for science."
Therein lies another major problem: Carrying out extensive surveys on animals that have learned to hide from humans isn't cheap. Though the conservation movement in Vietnam isn't exactly red-hot, scientists don't have the cold hard cash to fund one either. Local conservation groups can't afford to commit the time and staff needed for intensive inspections of far-flung forest nooks where a few dozen nocturnal tree-dwelling creatures might be hanging out. And in many primate conservation hot spots around the world mostly developing countries with limited resources the health and safety of humans naturally take priority over the welfare of our closest relatives. "Primatologists realize it's a luxury to afford to think about these species," says Wrangham. "But we don't have time to say, 'Let's leave the thing and hope for the best.' Some of these species are going to go extinct very quickly."
As a result, all four of Vietnam's Top 25 endangered primates have been "adopted" by foreign organizations. Groups like the Endangered Primate Rescue Center, founded largely on foreign initiative, help keep track of primate populations and train local scientists how to protect them. And while it may foster a habit of donor dependency, the collaboration between local preservation groups and NGOs pays off. One Vietnamese specialist whom Rawson trained has helped record the country's largest single group of grey-shanked douc langurs, a gorgeous monkey with an orange face and white beard that lives in the highlands of central Vietnam. Some organizations have even hired primate hunters, whose keen tracking skills make them useful for surveying elusive populations. "It's a matter of engaging the local people so they have some input," says Rawson. "Making sure they get some benefit from it as well."
Conservationists will also have to strike that kind of bargain with the world's governments if they hope to preserve threatened species. But the face-off between environment and development has been a perennial battle and perhaps, for primate conservationists, an unwinnable one given that the countries that are home to highly endangered primates, like Vietnam, are also home to developing economies. That's a discouraging reality for primatologists and for the grey-shanked douc, whose forest habitat in Vietnam is being destroyed at the rate of the 10,000 hectares per year to make way for logging and agriculture. "When it comes to a choice between economic development and protection, economic development is going to win out most times," says Rawson. "You're talking about the welfare of the country's citizens."