Leopards are being wiped out by illegal hunting in one of their strongholds in South Africa, experts have warned.

A study of the population in Soutpansberg Mountains found numbers had declined by nearly two-thirds in just eight years.

Leopards are classed as vulnerable on the International Union for Conservation of Nature’s Red List of threatened species.

A leopard and cub in the Soutpansberg Mountains, South Africa, where the population has crashed amid illegal hunting (Durham University)

The smallest of the big cats, they can be killed by lions, hyenas and other big predators, which they try to avoid by hunting at night and then carrying their kills high into the trees.

However, the researchers found the biggest threat to their population was humans.

Dr Samual Williams of Durham University, who led the study, said: “Illegal human activities like shooting, snaring and poisoning were the leading cause of death in the leopards we tracked.

“This was often in response to a perception that leopards were a threat to livestock.

“There is a clear need for conservation efforts to address these illegal killings.

“Educating communities and supporting them to adopt non-lethal techniques to help protect their livestock is essential.”

Camera traps were set up in 23 places in the mountains, running continuously between 2012 and 2016, to gauge the leopards’ numbers. Eight leopards were also fitted with GPS collars. Six of them died during the study.

The researchers found that the density of leopards fell by 44 per cent between 2012 and 2016 and 66 per cent since 2008, they reported in the journal Royal Society Open Science.

“If the current rate of decline is not slowed down then there will be no leopards left in the western Soutpansberg Mountains by 2020,” Dr Williams said.

“This is especially alarming considering that in 2008 this area had one of the highest leopard population densities in Africa.”

The trophy-hunting of leopards is currently banned in South Africa while more information about their numbers is collected.

The researchers urged the authorities not to allow hunting to resume in places like Soutpansberg because of the sharp decline in population.

“In areas such as this trophy-hunting is a luxury that cannot be afforded,” Dr Williams said.

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“Large carnivores like leopards are hugely important to the ecosystem of an area and also carry significant economic and cultural importance.