Indonesia: Sumatran Tiger Castoffs May Hold Key to Survival of the Species

Fidelis E. Satriastanti Jakarta Globe 7 Sep 11;

Cisarua, Bogor. Behind an unassuming gate, marked simply with a “Staff Only” sign, deep inside the Taman Safari Indonesia conservation park, lies the best chance for the continued survival of the critically endangered Sumatran tiger.

This is the Sumatran Tiger Breeding Facility, set up in 1992 and now home to 22 “troubled” tigers — those that have been trapped by poachers or villagers, those that have preyed on livestock and those believed to have killed and eaten humans.

Each of the 11 male and 11 female tigers here have their own harrowing history. Two of them, Salamah and Ara, female juveniles caught in boar traps set by villagers inside palm oil plantations in Aceh, had to have a paw amputated because of the seriousness of their injuries. Though accused of being man-eaters, the accusation has never been proven. At the park, they are affectionately referred to as “tripods.”

The latest addition is Tupan, an 8-year-old male who was brought to the facility on the verge of death.

Like many of the others, he was caught in a trap in his natural habitat after spooking villagers with his frequent encroachments into their area. When wildlife authorities reached him, they found he had been shot twice several days before being captured.

Following intensive treatment, he has made a full physical recovery.

“Most of the tigers that we keep here are disabled to some extent,” Retno Sudarwati, a senior veterinarian at the park, tells the Jakarta Globe.

“We have three-legged tigers, tigers who have had their tails lopped off, even toothless tigers. They need to be in peak physical condition to survive in the wild, so can you imagine them going after prey on just three legs? They wouldn’t survive long out there.”

Health, Hygiene, Happiness

Each tiger gets its own cage here, furnished with a log that they can sharpen their claws on, a hammock where they usually nap and a small pond to drink from. They also get an adjoining outdoor play cage and another cage where the keepers feed them.

The park also has a breeding facility that the tigers take turns occupying. Unlike their home cages, the “Rumah Batak” breeding facility is open to visitors.

“I know it’s not the kind of sophisticated facility that you’d probably imagine, but we do pay serious attention to the cleanliness of the cages and the tigers’ health.” Retno said.

“We keep detailed records of each and every one of them. If they exhibit the slightest issue, the keepers are obliged to inform us.”

Careful Calculation

The tiger facility is not just about saving maimed or threatened individuals. Its mission is far more important: to ensure the continued existence of the species by creating a genetically diverse gene pool from the animals it hosts, as well as those held at every zoo in the country.

“It’s not just about putting a male and a female tiger together in a cage and expecting them to mate, nor is it about producing a set number of cubs.” Retno said. “It doesn’t work that way. Each tiger is paired off with the best candidate. It takes a lot of careful calculation to ensure the purity of the gene pool.”

For example, Tupan would never be mated with Lintang, a female adult, because their bloodlines are too similar.

Instead, he would be paired off with females like Tina or Jenaka to produce an entirely new bloodline.

“The bottom line is that we want to make their bloodlines as varied as possible,” Retno said. “We want to make sure that over the next five years, we can prevent inbreeding as much as possible.”

To that end, the facility has compiled a stud book — a registry of the known parentage of all the tigers ever tagged in the country, whether in the wild or in captivity. This allows scientists at the park to work out which individuals are best suited for pairing to ensure a diverse gene pool.

Sperm Bank

Though painstakingly clinical, putting together the stud book is the basis for making sure that no matter what happens to the wild population of the species, there will always be enough variety in the genetic resources available to sustain the species.

That means collecting sperm from all the tigers held in captivity in the country since 1995. All that sperm, which makes up the Sumatran Tiger Genome Resource Bank, is stored at the park in containers kept at a frosty minus 180 degrees Celsius.

“This sperm bank is the stock, just in case something happens, we still have their sperm,” Retno said.

However, she points out that regenerating the species simply from the stored sperm is something the park does not yet have the technology to do.

“We’re still developing the technology to make use of this resource, so we’re getting there,” she said.

The Sumatran tiger is one of five remaining tiger subspecies in the world, and is also the most threatened, with only 400 individuals believed to be remaining in the wild. Categorized as critically endangered, it is just a step away from being extinct in the wild.

It is the only tiger left that is endemic to Indonesia. Two other subspecies, the Javan tiger and the Balinese tiger, were driven to extinction in the 1930s and 1980s, a fate that Retno and her team at Taman Safari do not want to see befall the Sumatran tiger.

“This facility here is our backup. If we could turn back time and breed the other two species the same way, we might still have them today,” she said.

The irony that the fate of the Sumatran tiger rests with a handful of individuals deemed most threatening to humans or unfit to survive in the wild is not lost on Retno.

“These animals are rare and precious individuals,” she said. “We can’t just kill them because they’re man-eaters or maimed, but we can make the most of them as a valuable resource in our conservation efforts.”