Gaborone: Botswana is investigating a growing number of unexplained deaths of elephants, having confirmed 275 had died, up from 154 two weeks ago, the government said on Thursday.
The dead elephants were first spotted months ago in the Okavango Panhandle region, and the authorities say they have since been trying to discover the cause. Poaching has been ruled out as the cause of death, as the carcasses were found intact.
“Three laboratories in Zimbabwe, South Africa and Canada have been identified to process the samples taken from the dead elephants,” the Ministry of Environment, Natural Resources, Conservation and Tourism said in a statement.
In a report prepared for the government and seen by Reuters, Elephants Without Borders (EWB), a conservation organisation, said that its aerial surveys showed that elephants of all ages appeared to be dying. The group counted 169 dead elephants on May 25, and another 187 on June 14, according to the report.
The directors of EWB did not immediately respond to phone calls or text messages seeking comment on the report.
“Several live elephants that we observed appeared to be weak, lethargic and emaciated. Some elephants appeared disorientated, had difficulty walking, showed signs of partial paralysis or a limp,” the report said.
“One elephant was observed walking in circles, unable to change direction although being encouraged by other herd members.”
The report said urgent action was needed to establish if the deaths were caused by disease or poisoning.
Africa’s overall elephant population is declining due to poaching, but Botswana, home to almost a third of the continent’s elephants, has seen numbers grow to 130,000 from 80,000 in the late 1990s.
However, they are seen as a nuisance by some farmers, whose crops have been destroyed.
President Mokgweetsi Masisi lifted a five-year ban on big game hunting in May last year but the hunting season failed to take off in April as global travel restrictions meant hunters from many coronavirus-hit countries could not enter Botswana.
Botswana is home to a third of Africa’s elephants, and there are concerns that whatever is causing the deaths, first recorded in May, could affect animals in neighbouring countries.
Following are some theories as to what could be behind the unexplained deaths.
POACHING
The government and conservationists ruled out poaching at an early stage because the carcasses have been found intact, with their tusks on.
Africa’s overall elephant population is declining due to poaching, but Botswana has been an exception, with elephant numbers growing to 130,000 from 80,000 in the late 1990s.
POISON
Poachers sometimes use poisons like cyanide to kill elephants before removing their tusks for ivory. But scavenging animals do not appear to be dying near the carcasses, which would be a sign that poison was to blame.
ANTHRAX
Anthrax, an infectious disease caused by spore-forming bacteria, sometimes affects wildlife in Botswana. But government veterinary experts say samples taken from the dead animals in the Okavango Panhandle did not contain traces of anthrax.
ALGAL BLOOMS
Another possible cause could be algal blooms, which can make water toxic to large animals.
As many as 70% of the dead elephants have been found clustered near watering holes. But other animals do not seem to be dying in large numbers.
DROUGHT
Drought is a common cause of death in arid parts of southern Africa, but it has rained in the Okavango Panhandle in recent months, and researchers who have visited the area say there is ample water.
A NOVEL PATHOGEN?
Conservationists have speculated another pathogen - a known or novel virus or bacteria - could be at fault.
Researchers have reported seeing live elephants that are physically weakened or wandering in circles, an indication of neurological impairment. Some were found face down, which could indicate a sudden death.
The government says it has sent samples from dead animals to laboratories in Zimbabwe, South Africa and Canada for further tests.