Sad news coming out of Vietnam today: the Javan rhinoceros subspecies (Rhinoceros sondaicus annamiticus), once endemic to Southeast Asia, has been confirmed as extinct, according to WWF International. There are now officially no rhinos left in Vietnam.

This is the second of the three Javan rhino subspecies to be hunted into extinction. The first, the Indian Javan rhinoceros (R. sondaicus inermis), disappeared more than a century ago. Now only the Indonesian Javan rhino (R. sondaicus sondaicus) remains alive, and it might not last much longer either. Just 50 or fewer of these animals are thought to exist in Ujung Kulon National Park on the island of Java.

All rhino species worldwide are heavily threatened by rampant poaching for their horns, which are sold for upward of $30,000 each for use in so-called traditional Asian medicine, even though they are of no actual medicinal value. There are two other Asian rhino species: the one-horned Indian rhinoceros (Rhinoceros unicornis), which numbers about 3,000 animals in the wild, and the critically endangered Sumatran rhinoceros (Dicerorhinus sumatrensis), which has two subspecies with a combined population of less than 300 individuals. A third Sumatran rhino subspecies may or may not still exist. In addition, there are two African rhino species: the white rhinoceros (Ceratotherium simum)—which includes the southern white rhino (the healthiest rhino subspecies, with more than 17,000 animals) and the northern white rhino, which is now down to its last seven individuals—and the black rhino (Diceros bicornis), with three critically endangered subspecies (two of which are below 1,000 individuals) and a fourth subspecies that was last seen in the year 2000 and is now believed to be extinct.

What is now known to have been the last Vietnam Javan rhino (the subspecies's official name) was killed by poachers in April 2010. At the time, scientists estimated that there might have been up to eight of these elusive, rarely photographed rhinos left in Vietnam. Now it seems that already low estimate was too optimistic. Genetic analysis of 22 dung samples collected by a WWF survey team in 2009 and 2010 reveals that they were all from a single rhino—the same one shot by poachers last year.

"The last Javan rhino in Vietnam has gone," Tran Thi Minh Hien, WWF-Vietnam country director, said in a prepared statement. "It is painful that despite significant investment in the Vietnamese rhino population conservation efforts failed to save this unique animal. Vietnam has lost part of its natural heritage."

The Vietnam Java rhino was actually thought extinct for more than 50 years, but it was rediscovered in 1988 when a single animal was killed by hunters. Since then, camera traps only captured a few images of the rhinos and the only time scientists actually laid eyes on one was the de-horned corpse found last year.

Despite the millions of dollars of international conservation funds poured into what was thought to be the last hold-out in Vietnam for R. sondaicus annamiticus—Cat Tien National Park—a WWF report released today (pdf) on the rhino's extinction says insufficient measures were taken to protect those few surviving rhinos from poachers who sought their valuable horns. The report blames "poor protection and law enforcement efforts and ineffective protected area management" and warns that "Vietnam is on the verge of an extinction crisis with many other species threatened by hunting and habitat loss." WWF is calling for improved law enforcement and management of key habitats "to ensure that other species do not share the same fate as the Javan rhinoceros." More specifically, said Nick Cox, manager of WWF's Species Programme in the Greater Mekong, "Vietnam's protected areas need more rangers, better training and monitoring, and more accountability."

WWF is also calling for increased efforts to protect the last Javan rhinos in Indonesia, before they, too, are also poached into extinction.

Updated: I asked Dr. Barney Long, WWF's Asian species expert, for some additional information on the Javan rhino, which came in after this story was first published. Here are his answers:

I covered the news of the death of this rhino in May of last year. Why did it take so long to get the genetic test results?

This was a complicated process working with genetic material that is the property of Vietnam so we had to go through due process. First we had to get permission to export and import all the dung that we collected during the rhino surveys. We then had to repeat this for the dead rhino material. Each of these samples were then analyzed in Canada at Queen's University. Genetic testing is not a quick process, especially on species such as the rare Javan rhino on which little genetic work has been conducted. These individual analyses then needed to be compared to check, double-check and triple-check so that we can be sure that all samples all came from the same individual. We had to be sure that we had the result 100 percent correct in this matter.

The press release mentions the "significant investment" in conservation of this species. Are you able to release a figure to quantify this?

International conservation organizations have been supporting Cat Tien National Park for many years and development projects have been run by international development agencies around the park. Also the Vietnamese government has been investing in the park. Work on rhino conservation and Cat Tien National Park has been on-going since 1988 at various levels of investment by various organizations.

Since this Vietnamese subspecies was so hard to count over the years, how confident are you in the estimates of the population on Java?

The simple answer is that we currently are not that confident. Our best estimate is 27-44 individuals based on camera-trapping. There is currently a scientifically robust survey being designed and piloted, by WWF, the International Rhino Foundation and many partners including the government of Indonesia and the Ujung Kulon National Park authority. This will use genetic studies to identify how many rhinos there are in Ujung Kulon National Park, the only place left with Javan Rhinos. Once this is completed we will be confident of the numbers when they are calculated.

Are there any thoughts on how common this subspecies might have been historically?

Historical records show us that it was found across Java and Sumatra in Indonesia as well as Vietnam, Cambodia, Lao, Malaysia, Thailand, Myanmar, Bangladesh and NE India—clearly a very large area, although it was probably restricted to certain habitats within this area. So at some point in the past there must have been many thousand.

What action would you want people to take (if any) to help protect the remaining subspecies in Indonesia?

All partners are working together to save the Javan rhino in Indonesia. WWF has a campaign to support this, as do IRF. Supporting these organizations would be the best way to help.

Photo 1: The skeleton of the last Javan rhino in Vietnam. Photo 2: a rare image of the Javan rhino, via a camera trap in Cat Tien National Park. Photos © and courtesy of WWF-Greater Mekong