DNA taken from 69 crocodiles housed in the moats of the Phnom Tamao Wildlife Rescue Center showed nearly 50 percent were Siamese crocodiles, which until recently were believed to have become extinct in the wild, researchers said Wednesday.
"For the first time in Cambodia, we have a captive population of animals that we know 100 percent are purebred Siamese crocodiles," said Adam Starr, who manages the Cambodian Crocodile Conservation Program, a joint effort between the government and Fauna & Flora International. The Washington, D.C.-based conservation group Wildlife Alliance also took part.
Once common throughout Southeast Asia, the Siamese crocodile or crocodylus Siamensis is locally extinct in 99 percent of the areas it once roamed and is listed as critically endangered by the International Union for Conservation of Nature. Much of the wild population was wiped out by habitat loss and poaching.
Those left in the wild - thought to be less than 250, with nearly all in Cambodia and the rest in Indonesia and Vietnam - face the new threat of hydropower dams being built in two of their three known habitats in the country.
Starr said the discovery of the captive population would give conservationists new options for breeding and reintroducing the crocodiles into the wild, most likely in places not affected by the dams. He said up to 60 crocodiles a year could be released into areas where they once thrived.
DNA analysis, which was done at Thailand's Kasetsart University, is necessary because it is virtually impossible to tell the difference between Siamese crocodiles and the hybrid crocodile species that are also housed at the center.
Nhek Ratanapech, director of the wildlife center, said he was surprised to learn that so many of the crocodiles turned out to be pure Siamese.
"Before we conducted the DNA testing, we thought perhaps only three or four of them in the zoo were Siamese crocodiles," he said.
Siamese crocs are said to be a bit smaller at just under 10 feet(3.5 meters) than hybrids, and their snouts are shorter and wider.