In May and June 2020, the death of 350 elephants in Botswana’s Okavango delta baffled conservationists and sparked global speculation about what had caused it. Elephants of all ages and both sexes were affected, with many walking in circles before dying suddenly, collapsing on their faces. Two months later, 35 more elephants died in north-western Zimbabwe.
At the time, the deaths in Botswana were attributed to an unspecified cyanobacterial toxin, government officials said, and no further details were published.
