Amur Tigers Threatened by Limited Gene Pool
Alaska Zoo brothers part of shrinking population worldwide
ANCHORAGE - Like any other pet owner, zookeeper Jim Rutkowski loves his cats.
But the two Amur tigers he cares for at the Alaska Zoo are a far cry from your garden-variety house cat. As Rutkowski pressed up against the fence at the back of the tiger's enclosure Thursday afternoon, eight-year-old Kunali pulled his lips back and growled, separated from his handler by only a few inches and a wire fence.
"You're a big kitty!" Rutkowski purred to his charge. "Isn't he beautiful?"
Kunali and his brother had been raised in captivity, but life wasn't so easy for their relatives in the wild. In fact, poaching and the disruption of their habitat in the Amur Region of Southern Russia was a deadly one-two punch for the tigers, and Rutkowski said the shrinking population was struggling to hold on. While there was enough game in the area to support around 700 tigers, the population had dipped to roughly 500.
According to a study published recently in the journal Mammalian Biology, the numbers were even drearier than that. The study reported an effective population of only 14 tigers worldwide: the number referred to genetically diverse animals, and researchers said a low rate of genetic diversity led to high disease rates and a plethora of genetic disorders. Rutkowski said similar problems had already taken their toll on other subspecies of tiger: The Caspian, Bali and Java tigers had all gone extinct.
"You know, once you get a tiger below a certain population count, their chances of breeding to get the population back up is impossible," he said.
More than 100,000 tigers roamed the globe at the turn of the century, but just 100 years later, the zookeeper said the number shrunk to only a few thousand.
"That's a drastic amount, and if it kept going like that, you wouldn't see any more tigers in a few more years," Rutkowski said. "They'd be extinct."
That's where the Species Survival Plan (SSP) comes into play - a breeding program set up in zoos and conservation centers around the country. The Alaska Zoo is not currently involved with the program, but Rutkowski said he'd love nothing more than a litter of tiger cubs to raise like the two he cares for now.
"I don't have any children, so I guess these are my children," he said.