Hong Kong is acting as the gateway for illegal ivory entering China - where the item is high in demand.
Prince Charles and Prince William joined launched a campaign to save endangered species like rhinos, tigers and elephants from poachers.
Poaching is threatening the very existence of elephants and rhinos across Africa, as wildlife parks struggle to keep up with their methods.
Horrified tourists on safari in South Africa discovered a mutilated rhino wandering around what is supposed to be a nature reserve whilst on holiday last week. The rhino, seen stumbling and bleeding around Kruger National Park, was filmed by the visitors.
South Africa earlier in the year warned that rhino poaching increased 50% last year, due to growing demand from Asia.
The film, shot on February 28, shows the animal swaying with blood streaming from where its horn has been hacked off. It was put down shortly after being discovered, the Daily Mail reports, as it was in agony.
Reynold Thakhuli from South African National Parks told the Daily Mail:
"An assessment was conducted to determine the extent of the injuries and suffering. It was discovered that a bullet had lodged in the rhino’s brain and therefore any chance of survival was slim".
Warning: Viewers may find this footage distressing
Conservationists are warning that the rise in poaching, to meet demand for rhino horn in China and Vietnam in particular, are bring South Africa's rhino population to the "tipping point" of extinction.
The Duke of Cambridge has hailed tomorrow's major international summit on the trafficking of endangered wild animals as the "beginning of the end of this despicable trade".
Speaking at a Natural History Museum reception attended by conservation charities, philanthropists and leading wildlife campaigners Prince William said:
"Tonight we are here with a single, shared purpose - to use our collective influence to put a stop to the illegal killing and trafficking of some of our world's most iconic and endangered species."
During the event William met one of the world's biggest action movie actors Jackie Chan who is in London to launch an anti-poaching video for the organisation WildAid of which he is an ambassador.
Prince William's decision to go hunting in Spain shortly before he makes a speech at a conservation conference is just 'poor PR' and should not distract from the major issues, an expert has told Daybreak.
Will Travers from the Born Free Foundation said hunting and poaching "were not the same thing", with the latter being a "£12bn international illegal wildlife trade".
Prince William will give a speech tonight to mark the imminent start of an international conference that aims to tackle the threat to the world's endangered animals.
William will make an address at a Natural History Museum reception as world figures prepare to discuss ways of saving animals like elephants, rhinos and tigers tomorrow.
His father Prince Charles will give a speech at the London Conference on the Illegal Wildlife Trade being hosted by the Government at Lancaster House on Thursday. William will also attend and it will be hosted by the Prime Minister.
William has joined forces with the Prince of Wales to record a video message calling on the world to act now to save endangered animals.
In a father-and-son appeal video with Prince Charles, The Duke of Cambridge tells of how he is "devoted to protecting the resources of the earth" for his own son, and future generations.
In a joint video appeal with his son William, Prince Charles said that the illegal wildlife trade now poses "a grave threat" to both endangered species and economic and political stability.
– The Prince of Wales
I have said before that we must treat the illegal wildlife trade as a battle, because it is precisely that.
The rising and apparently insatiable demand, much of it from Asia, has provided an economic incentive for trafficking to become increasingly criminalised and professional.
Organised bands of criminals are stealing and slaughtering elephants, rhinoceros and tigers, as well as large numbers of other species, in a way that has never been seen before, pushing many species to the brink of extinction.
Prince Charles and Prince William have released a video appeal to end the illegal wildlife trade, in a bid to save endangered species from extinction.
In the video, Prince Charles describes the illegal wildlife trade as a "battle" and attacks an "apparently insatiable demand" for endangered animals.
The pair recorded the video appeal in six different languages.
The Duke of Cambridge and Prince Harry have reportedly gone hunting in Spain - a day before William and his father, the Prince of Wales, call on the world to combat the illegal wildlife trade.
The royal brothers are set to hunt wild boar and stags on a private estate, according to The Sun.
In a video message due to be broadcast tomorrow, Charles and William will call on people to act now to save endangered animals like rhinos, elephants and tigers.
A royal spokesman told ITV News they would "never" confirm what the princes do in their private time. He added:
"The Duke of Cambridge has for many years been a passionate advocate for endangered wildlife and has campaigned tirelessly to help stop the illegal poaching of rhino horn and elephant tusk. His track record in this area speaks for itself."