Tigers may be going extinct. There were once 100,000 of the grand animals, but today just a few thousand survive.
How do we save them and other endangered species? Well, here's an idea: Let's eat them!
Wild tigers are disappearing because poachers kill them for their skins and to get crushed tiger bone, which is made into paste that some people use as a painkiller.
Actor Harrison Ford does public service announcements supporting the international ban on the sale of exotic animal products.
"When the buying stops, the killing can too," he says in the PSA. "Case closed!"
But the case isn't closed, because outlawing buying and selling hasn't worked. The international ban has been in effect for 33 years, but the population of wild tigers has continued to shrink.
Watch John Stossel's special "You Can't Even Talk About It" tonight on "20/20" at 10 p.m. ET
Grace Gabriel, Asia regional director for the International Fund for Animal Welfare, says what's needed to save the tigers is better law enforcement.
"There needs to be judicial systems in place so that there will be punishments for wildlife crimes [that are] strong enough to have a deterrence power."
But Terry Anderson from PERC, the Property and Environment Resource Center, disagrees.
"If we continue the current approach of no killing, no trading, I think the tiger is doomed," he said.
He believes governments have repeatedly failed when they tried to save animals by banning their sale.
PERC suggests the opposite: let people own wild animals, farm them and sell them.
That's what saved another species. High in the mountains of Montana, Pam and Craig Knowles raise bison.
Millions of these animals once roamed America, but 100 years ago they were almost extinct. Why? Because no one owned them. No ranchers like the Knowles had the incentive to protect them, and people killed them and sold their hides.
"There were a few trappers who saw what was going on and said, this is wrong," said Pam Knowles. "Here's an animal that could provide the whole country with meat."
So people began to fence bison in and eat them. Now America has half a million bison -- that's a way to save animals.
Does America have a shortage of chickens? No. Because we eat them. Do we have a shortage of minks? No. Because people have a reason to protect them.
In Africa, rhinos were disappearing because poachers killed them for their horns. African governments banned poaching, but this did little good.
"We're talking about countries, governments and police forces that are often involved in the poaching," said Anderson.
Some government game wardens took bribes, or slept on the job.
"It was a complete failure," said Dr. Brian Child, associate professor of African studies at the University of Florida, who spent years in Africa trying to save rhinos. "Wildlife was disappearing everywhere."
What finally worked, he said, was letting landowners own them and make money off tourism. Suddenly each tribe had skin in the game, and an incentive to protect its own rhinos. Those indifferent security guards became fierce protectors of their tribal rhinos. Anderson asked one what happened if he caught a poacher.
"He said, 'We don't kill them, we just beat them up badly enough, they go back to their village, and don't ever come back,'" Anderson said. "These people don't tolerate poaching because they want to keep the animals alive. They allow hunting. They allow photography. That is the way to save wildlife."
And it's worked.
But Judy Mills, Conservation International's wildlife trade advisor says that farming tigers won't necessarily stop poaching.
"Bears are farmed in China. There is more than enough bear bile to go around to the whole of China. [But] wild bears are still being poached for their gall bladders."
And this is true. It's impossible to stop all poaching. Rhinos too are still being poached. But their numbers have steadily grown since farming began in Africa.
"There are a lot more rhinos alive on private land where there were no rhinos 50 years ago, 40 years ago," said Child.
Right now in China, thousands of tigers survive only because some tiger farms protect them. About a dozen farms are currently breeding tigers, and their owners hope that next year the Chinese government will lift its ban on tiger sales.
Gabriel believes that would be a disaster for wild tigers. She says it's expensive to raise farmed tigers, and legalizing the sale of tiger parts would just increase poaching.
"If you allow farmed tigers to be traded on the market, you're going to restimulate demand," she said. "You're going to undermine over a decade of conservation work to reduce demand."
But Anderson says "that's a silly idea."
"It ignores what supply and demand is all about," he said. "Legalizing trade is not going to increase the demand. Farming is a way to take the pressure off of those wild tigers."
So who's right?
"Let me tell you about a survey that we did recently in China, which showed that 90 percent of Chinese people actually support the ban," said Mills. "They support the ban, and they see the greater good in keeping the ban in place."
But many of the same people who supported the ban also admitted to having products made from tiger bone.
Gabriel says we need more time to educate the Chinese consumer, that "we haven't had a lot of time to work at all the steps" to reduce the demand in China for tiger products.
But how long can we wait? Mills claims the ban has worked in America, where it's illegal now even to sell medicines that pretend to contain tiger parts. But even in relatively law-abiding America, we easily found these products in New York City's Chinatown neighborhood that used images of tigers to promote sales.
Nonetheless, Mills says, "The bans have worked tremendously. By my calculations, more than 2,000 tigers are still alive in the wild today because of the ban."
But thousands more have vanished because people aren't allowed to own and sell tigers. It's quite the conceit that a few conservation groups think a government decree can get a billion-plus people to just change their culture.
"The demand is there by people for thousands of years who have felt that this is a useful medicinal product for them," said Anderson. "That isn't going away."
So it makes sense that farming tigers will meet that demand. But Judy Mills disagrees.
"Believing that farming tigers and reopening trade in their products will somehow save wild tigers is magical thinking," she said.
Magical thinking? No. Anderson says farming has already worked with elephants in Botswana, rhinos in southern Africa, and the bison in America. He believes it will work again with tigers in China.
"If we make animals a marketable product," said Anderson, "they will be saved. "