Hundreds of Elephants Have Suddenly Died and No One Knows Why

Hundreds of elephants have died in mysterious circumstances in Botswana over the past two months, with experts describing the situation as a "conservation disaster."

At the beginning of May, the government of Botswana, a landlocked country in southern Africa that boasts the world's largest elephant population, announced that a cluster of deaths had been found in the Okavango Delta.

By the end of that month, the number of elephant carcasses discovered stood at nearly 170, but subsequent investigations have brought the total to more than 350—with 70 percent of the deaths clustered around waterholes—although the true number is likely to be higher, conservationists say.

At present, experts still don't know why the animals are dying and the Botswana government has yet to complete testing of the elephant remains, which could reveal what is behind the deaths.

"This is totally unprecedented in terms of numbers of elephants dying in a single event unrelated to drought," Niall McCann, from the U.K.-based charity National Park Rescue, told the BBC.

In May, the government ruled out poaching as a case of the deaths because the elephants' tusks had not been removed.

"So far, veterinary officers have ruled out the possibility of poaching because all carcasses of the elephants were found intact," Oduetse Koboto, the Botswana tourism ministry's acting permanent secretary, said in a statement in May.

One possible cause could be cyanide poisoning, a technique sometimes used by poachers in southern Africa. However, this seems unlikely given that animals scavenging the carcasses do not appear to be dying as well.

"It is only elephants that are dying and nothing else," McCann said. "If it was cyanide used by poachers, you would expect to see other deaths."

Another possibility considered by experts was natural anthrax poisoning, which is thought to have led to the deaths of at least 100 elephants last year in Botswana. However, McCann said this has also been tentatively ruled out.

Nevertheless, the possibility remains that the elephants died due to an unknown pathogen or another kind of poisoning.

There are some indications that the elephants suffered some kind of neurological impairment prior to death—for example, the way they are dying and the fact that local eyewitnesses have observed some of the animals walking in circles.

An elephant in the Okavango Delta, Botswana, on September 28, 2019. MONIRUL BHUIYAN/AFP via Getty Images

"If you look at the carcasses, some of them have fallen straight on their face, indicating they died very quickly. Others are obviously dying more slowly, like the ones that are wandering around. So it's very difficult to say what this toxin is," McCann told The Guardian.

Because there is a chance that the elephants could be dying of an unknown disease, McCann said the possibility of the pathogen responsible jumping into humans is also impossible to rule out at this point.

"Yes, it is a conservation disaster, but it also has the potential to be a public health crisis," he said.

Botswana is home to more than 130,000 elephants—around a third of the African total. However, the continental population is in decline with the animals facing threats from poaching, habitat loss and fragmentation and human-elephant conflict, according to the World Wildlife Fund.