The mystery was over when adult elephants began to be found dead in the estuary of the Okavango River in Botswana. It couldn’t be a poaching hunt because the most valuable parts of the elephants – the incisors – were still in place.

Drought was also not a cause of death because elephants have perished near drinking water. Some had died directly on their first sip from Okavanga. They were found head still deep in the river.

The problem only affected elephants, which in turn limited the poisoning out of the bills.

Local limnologists have now found that there is a cyanobacterial neurotoxin in Okavango.

– The latest sample has confirmed the cause of death of cyanobacteria. We found it in the river, scientist Mmadi Reuben confirmed.

However, the questions do not end there.

– We still want to get an answer as to why only elephants died and why only in this area. We have several theories that we are currently exploring.

More than 20 elephant carcasses were found in neighboring Zimbabwe. They, too, are feared dead to bacterial poisoning.

The number of elephants has collapsed in Africa due to poaching. Botswana still has about a third of the continent’s elephant population.