It costs £500 a night to stay in a luxury safari camp in the Kalahari desert in Botswana. For that price, wealthy tourists get drinks, game drives and, says one tour company, an "interpretive Bushman walk with staff members who hail from the ancient Bushman clans of the area". Visitors watch half-naked men shooting bows and arrows in the sand dunes and, if they get permission, can pay to shoot giraffe, zebra and other wildlife with guns.

For Jamunda Kakelebone, a 39-year-old bushman, or San, whose family has always lived as hunter gatherers, what is happening in the Kalahari desert is deeply disturbing. Not only have bushmen families like his been moved from their ancestral land to make way for tourists, diamond mining and fracking, he says, but those who remain are now no longer allowed to hunt.

The final blow came in January, when a ban came into effect prohibiting all hunting in the southern African country except on game farms or ranches. The new law – announced by the minister of wildlife, environment and tourism, Tshekedi Khama (brother of the president, Ian Khama) – effectively ends thousands of years of San culture.

Jamunda Kakelebone and British lawyer Gordon Bennett visit Clarence House with letter for Prince Charles. Photograph: Ik Aldama/Corbis

"We have survived for millennia in one of the world's driest areas but they treat us as stupid. We are hunter-gatherers yet we get arrested. We cannot damage the wildlife. If we kill one animal we eat it for a month. We are not allowed to hunt but others can," he told the Guardian.

San bushmen starting a fire in the Kalahari desert near Ghanzi, Botswana. Photograph: Alamy

Kakelebone has been London to petition Prince Charles and protest against the treatment of bushmen by the Botswana government. In a letter, he referred to the writer and conservationist Laurens van der Post, who invited the prince to the Kalahari to meet the bushmen in 1987.

"We have survived alongside the animals [there] since the beginning of time. We know how to look after them and we hunt them for our survival, not for entertainment like many tourists from your country do. We know that you walked with Laurens van der Post and the bushmen a long time ago. You know who we are. We are begging you to talk to president Khama and ask him to stop persecuting us," said the letter. Van der Post, who died in 1996, was also Prince William's godfather.

A lone bushman on a red sand dune. Photograph: Jaco Wolmarans/Getty Images

After visiting the bushmen, Charles wrote that they had greatly influenced his thinking about the environment. "What I discovered was the profound and intuitive ties that bind the bushmen to their land; their awareness of the workings of the natural world and of the delicate balance between life, physical surroundings and inner spirituality that they had maintained for so long in the harshest of environments … The bushman is an innocent victim of what, far too glibly, too many of us would call 'progress'... We all lose if the bushman disappears.'

But it has emerged that he and Prince William may have unwittingly encouraged president Khama to stop the bushmen hunting. In January, Charles and William hosted an international meeting to draw attention to a crisis of illegal poaching of animals like elephants and rhino at Clarence House, Charles's London residence. With the UK government, the royals are said to have helped persuade 46 countries to take new initiatives.

Khama, whose family owns a large tract of the Kalahari desert reserve and whose nephew has shares in one of the most expensive game lodges, was present at Clarence House in London and used the occasion to pledge to protect wildlife.

"Our president is doing this because he is interested in tourism. His family is making money out of this," says Kakelebone. "My people do not know anything about this ban on hunting. We are not going to stop hunting. My fear now is that they will arrest us and use the ban to put us in prison and drive us out of our homeland. The government is not telling people about this. We think they want a pretext to arrest us drive us out," said Kakelebone.

In a series of evictions after 2002, the Botswana government removed several thousand San from the Kalahari reserve, claiming they were a drain on Botswana's financial resources and that the families were happy to give up their hunter-gathering. But, say human rights groups like Survival International, the evictions were intended to allow in conservation groups, tourist companies and diamond mining.

Around 350-400 San people now live in seven "settlements" in and outside the game reserve, many of which are in appalling conditions. "Instead of being allowed to hunt, we are taken to resettlement camps and must depend on government for handouts. It's like holding your arms and expecting to be fed. They treat us as stupid. We are given clothes and food.

"They are destroying us, and the reserve and are saying we cannot go there. It's racial discrimination. They look down on us. They say 'they are only bushmen'. They say we are primitive and that elephants are better than us. They give us pounded sorghum, beans and sugar. They give us no meat at all. They want to change us to become pastoralists. When they remove is from the reserve they give us a few acres and cows and tell us to plough. It is totally changing us and our culture", said Kakelebone.

The Botswana government has long maintained that the San families chose to move but this was rejected by the Botswana courts in 2006 which ruled that the Bushmen had been forcibly and unconstitutionally removed. But the government interpreted this to mean that only the people who were part of the case had the right to return. In 2008, the United Nations Human Rights Council (UNHRC) criticised Botswana's government for not allowing certain San to return.

"My son is not allowed to stay in the reserve if he is over 18. He must apply for a one-month permit. This is systematic persecution. My grandfather used to tell me that he had nothing to give but the land. 'That is your heritage,' he said. If you take it you are killing us. If you deny us the right to hunt, you are killing us".

"Our death rate is increasing. They want to develop us. To eradicate us. They want us to speak English. I do not think they see us as people (because) they need to but they think that we are just trees or stones. They build us a clinic but our people die of HIV and TB. When we were on our own, our death rate was low. Old people died of age. Now we go to funerals. It's terrifying. In 20 years its going to be bye bye bushmen."

A spokesman for Prince Charles declined to comment.