The world's final 23 Hainan black-crested gibbons (Nomascus hainanus) are making what may be their last stand in China, where their jungle habitat is being wiped out at a rate of 200,000 square meters a day, according to a new report from Greenpeace International.

Hainan gibbons are the world's rarest primates. Sixty years ago they could be found all across Hainan Island in the South China Sea. Now they are limited to the 2,100-hectare Bawangling National Nature Reserve on the western side of the island. While the gibbons are legally protected, lack of enforcement has allowed illegal loggers and pulp paper plantation growers to take over 25 percent of the island's rainforests, including a portion of the apes' reserve habitat, in the past 10 years.

Via satellite images and field work, Greenpeace found that more than 72,000 acres of Hainan rainforest have been illegally cut down since 2001.

"This illegal deforestation comes in response to market demand and disrespect for nature," Greenpeace forests campaigner Yi Lan said in a prepared statement. "A lack of enforcement brought about this rapid loss of rainforest and it's about to bring about the extinction of a species."

According to the International Union for Conservation of Nature and Natural Resources (IUCN), the population of Hainan gibbons numbered more than 2,000 individuals in the 1950s. By 1993 that had declined to less than 60 apes due to hunting and habitat loss, much of it to build rubber tree plantations. A 2003 survey found only 15 apes, some of which have bred since then, bringing the total population today to 23. Female gibbons only breed once every two to three years, so the population's opportunities for further growth are slim.

"When you have just 23 of a particular animal species left in the wild, that says we humans aren't being good stewards of the environment," Lan said.

Greenpeace released this video (in Chinese with English subtitles) about the Hainan gibbons and the shocking deforestation in the area:

In addition to the illegal plantations, legal pulp paper plantations have also been established along the banks of the gibbons' protected reserves. These pulp trees require so much moisture that water levels have been depleted in some areas, causing native trees and plants to suffer and die. As they disappear, so goes more of the gibbons' habitat and food supplies.

Conservation efforts to preserve the Hainan gibbon have been slow to get off the ground. A conservation action plan (pdf) was established in 2003, but according to the IUCN Primate Specialist Group, its success has been limited by lack of coordination between the eight participating government bodies, universities and organizations. Most efforts to date have been restricted to surveying the apes and their habitat.

Greenpeace is calling for the Hainan government to enforce its laws for protecting the gibbons as well as the island's rainforests.

Photo: A female gibbon in Hainan. Courtesy of Greenpeace