Unusually no other wildlife species were affected by the toxic water in the Seronga area, close to Botswana's famed Okavango Delta, said Taolo.
With an estimated 130,000 elephants, Botswana has the world's largest population of the pachyderms, which attracts international tourists.
Most of the surviving elephants fled the area after the deaths, which occurred mainly near seasonal water areas and did not spread beyond that region.
Samples from the elephants carcasses were sent to laboratories for testing in Southern Africa, and now experts are saying the most likely cause is a cyanobacteria that lives in the water and could have caused paralysis and death mainly related to respiratory failure.
Dr. Niall McCann, director of the National Park Rescue's Conservation, told CBS News that many unanswered questions remain.
McCann also said there are different types of cyanobacteria and it's crucial to pinpoint exactly which one it is to mitigate against any future harm to the elephants.
He told CBS News that this period, the start of summer in the southern hemisphere, always brings blooms of toxic algae, and deaths from anthrax and other naturally occurring poisons are typical.
Original article