Botswana’s Environment Ministry ruled out anthrax and bacterial infections as the cause of death after 39 elephant carcasses were found since January.
The latest mortalities come after 330 elephants died last year from what the government said was a neurotoxin in waterholes.
In last year’s mortalities, scientists found toxins produced by a cyanobacteria residing in the silt below the surface of waterholes used by elephants. A severe drought was believed to have led to the emergence of the neurotoxin. The investigation put an end to months of speculation about the cause of death.
Botswana has about 130,000 elephants, the most of any nation.
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