ELIZABETH JACKSON: In South Africa, the first trial of a radical attempt to reduce rhino poaching in private game reserves has been hailed as promising.
In the past three years, rhino poaching in southern Africa, home to the largest remaining populations of rhino, has escalated dramatically, so that now almost one rhino every day is slaughtered for its horn.
But one farmer who lost two of his rhino's to highly skilled poachers is hitting back.
Here's our Africa correspondent Ginny Stein.
GINNY STEIN: It's feeding time at the Rhino and Lion Nature Reserve near Johannesburg. A young rhino who lost its mother is being fed one of its many bottles for the day.
What happened to these ones?
ED HERN: The mothers got killed, one in Krugersdorp Game Reserve right here and the other one in the Kruger National Park.
GINNY STEIN: The modern poacher is highly skilled. The operation to kill the mother of this baby rhino involved a shooter armed with a tranquiliser gun, a helicopter pilot and someone else wielding a chainsaw.
Last year game reserve owner Ed Hern lost two of his rhinos in a similar operation. From when Mr Hern heard the helicopter, until it was all over probably took 10 minutes. His rhino was dead and the poachers were on their way with a product worth a fortune in Asian markets.
ED HERN: In China, by the time it lands in China, it's probably worth a million American dollars.
GINNY STEIN: There's big incentive.
ED HERN: Indeed there is and that's why they can afford what they are doing. They can come in by helicopter, they've got the best night vision equipment that you can ever think of, they've all got bullet proof vests, they've all got AK47 rifles, so it is a big operation.
GINNY STEIN: South Africa is home to the largest remaining populations of white and black rhino. The number slaughtered has tripled in the past few years. Rhino's are now being killed at the rate of almost a rhino a day.
Private game reserves have been increasingly targeted by African gangs funded by Asian demand for rhino horn.
Ed Horn has had enough. To protect his animals he's come up with a plan. He initially wanted to use cyanide but has settled on something less lethal to whoever ingests even the merest portion of a horn from one of his rhinos.
ED HERN: If you eat the rhino horn for any reason you are going to fall ill. You are going to be vomiting, or you're going to have a stomach ache or whatever, but you are going to feel the consequences, you certainly would feel it, yes.
GINNY STEIN: And to make sure that there is no doubt, one of the six ingredients in the concoction he expects to soon start marketing includes an indelible dye, which ensures his rhino's horns stand out from the rest.
He says there is no danger to the animal if the process is done right.
ED HERN: There's blood vessels low down on the horn but not the upper portion, so as long as you don't do it to low down, if you inject it too low then obviously it will have an effect on the rhino.
GINNY STEIN: While private game reserve owners feel each death keenly, it's in the national parks where the largest numbers are killed.
Kruger National Park has lost 90 rhinos to poachers this year alone, but contaminating the horn is not feasible.
National Parks spokeswoman Wanda Mkutshulwa.
WANDA MKUTSHULWA: In the country we have over 20,000 rhinos. Will we be able to poison each and every one of those rhinos and what is the cycle of having to inject those animals with this poison?
GINNY STEIN: For wildlife professionals there is anger and frustration at an industry driven by superstition and greed.
Jacques Flamand is the director of the World Wide Fund for Nature's rhino breeding program in South Africa.
JACQUES FLAMAND: It is really useless medicinally and that is the sad thing is that animal products like rhino horn and most animal products are based on superstition and no valid medicinal value.
GINNY STEIN: For game park owners, they know changing people's beliefs is out of their hands. Their priority is trying to keep their animals safe.