Now the belief that rhino horn can cure cancer is apparently taking root, fueling some of the new demand.
"There is some mythology developing in Vietnam because somebody took rhino horn and went into cancer remission, or at least that is the information we're getting," Lieberman said.
"But it is not, and never was, a cure for cancer."
In addition, there's a lucrative market in Yemen and Oman for daggers with rhino-horn handles—often given to boys during rites of passage—said Cathy Dean, director of Save the Rhino. (See video on the rhino-horn knife trade in the Yemeni capital.)
Asian Appetite, African Menu
Growing wealth in Asia and increasing Asian-African trade also appear to be driving up demand for rhino horn.
"There seems to be evidence that the growing Far Eastern footprint in Africa has led to local spikes in poaching," Dean said.
The cost of protecting rhinos is also spiking, she added.
A Save the Rhino partner organization in Kenya was recently forced to increase its payments to antipoaching informants, because the poachers were paying larger bribes, Dean said.
Lax law enforcement in Zimbabwe is of particular concern, WWF's Lieberman added.
But in many countries—such as Botswana in Africa as well as Nepal and India in Asia—officials are simply being outmatched by well-financed, sophisticated poaching operations.
"This is the most dangerous [wildlife] trade right now, because it involves organized crime," Lieberman said. "This isn't the case of someone smuggling a few [products] across the border."
Combating the Trade
Some overwhelmed countries could benefit from hands-on help from countries such as the U.S. to stem the trade, Lieberman said.
Other countries such as China are competent at undercover investigations and simply need to make stopping wildlife crime a priority, she added.
For its part, Save the Rhino is focusing on raising the value of living rhinos and their habitat in the eyes of local communities.
Ecotourism operations are one way to increase the local value of rhinos, though Save the Rhino's Dean said the tourism trade is too fickle to guarantee a steady income.
Other avenues include trophy hunting, breeding-compensation programs, and sustainable "harvesting" of the animals, with the proceeds returned to rhino conservation, she said.
"Local communities have to have a say in rhino habitats that they manage," Dean said. "They need to see some form of economic reward and incentive."
Though the outlook is grim, WWF's Lieberman remains optimistic.
"There was significant poaching—almost at this level—15 years ago," she said. "It can be turned around with high-level government commitment and enforcement."
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