For months now Botswana wildlife officials have been reluctant # to blame the deaths of an estimated 330 (± 45 ) ** elephants, found primarily in the country’s Okavango Delta, (70% of those elephant deaths occurred near their water holes) on a toxic bacteria.
But as more conclusive results have come in from “specialist laboratories” in Zimbabwe, South Africa, America and Canada <> Botswana has been able to identify what they think has been the problem all along, a toxic cyanobacteria.
It is often found in stagnant water not unlike a wild elephant’s watering hole and can appear blue-green in color when larger blooms form (hence the term blue-green algae). <> Ingested in substantial doses it can be deadly to mammals such as elephants, causing paralysis, cardiac and respiratory failure, # which was the case with our elephants in Botswana as some appeared to be very disoriented before they died. (Elephant conservationist Niall McCann)
“Rising temperatures and intensive farming methods are fuelling an increase in algal blooms in rivers, lakes, reservoirs and seas around the world. Elephants are naive to this potential threat which makes them vulnerable.” Elephant conservationist Dr. Niall McCann, director of conservation at UK-based charity National Park Rescue
Doubts were initially raised regarding the toxicity of the bacterium in their water holes as elephants “tend to drink from the middle” <> while the algae blooms commonly “appear on the edges of ponds,” <> and because “elephants were the only species to die (with the exception of one horse)”. #
But officials now believe, that as elephants love to frolic and linger in the water, what with bathing and all, and as they tend to drink about 50 gallons of water a day, ingesting it through their trunks full of olfactory receptors # that they become more vulnerable to the deadly toxins than the other species of wildlife. Ironically, the mysterious deaths “ceased after the water pans (seasonal watering holes) dried up (approx. at the end of June 2020)” Cyril Taolo, acting Director of the Department of Wildlife and National Parks, stated.
There are other theories that have yet to be addressed, or at least are less publicly known, such as EMC, the “rodent virus” # quite commonly found in zoo elephants when their enclosures are infested with rats. (See the Elephant Encyclopedia Viral EMC – Elephant Encephalomyocarditis virus) EMC was also to blame for the 1993-1994 elephant deaths (64) in Kruger National Park
The Guardian # explains: “The fact that the elephant carcasses were close to water holes does not mean water was the source of the poison – frequently sick animals seek out water because they are feverish or thirsty. Farming is widespread on the floodplains of the Okavango delta and this year has seen a bumper crop of maize and sorghum because of late rains in 2020 following a string of dry years. This could have attracted families of elephants to cropland as well an increase in rodents, which defecate and urinate on tufts of grass. This means they would have been in close contact. Most grazers eat the leaf part of grass, but elephants grab grass with their trunk and eat the whole tuft (including rodent faeces), potentially exposing them to the EMC virus.” Yet “the Botswana government has ruled out EMC because there was no damage or abnormalities found on heart tissue of the animals, but it is not clear how many samples were tested” or how fresh (state of decomposition) those samples were (tissue from the dead elephants).
A valuable clue leading one to suspect EMC is the “single dead horse” # as horses are particularly susceptible to EMC
Mmadi Reuben, principal veterinary officer at the Department of Wildlife and National Parks is pressing on with the investigation, beyond the cyanobacteria diagnosis, determined to unearth ‘Why only elephants?’ , ‘Why only that area (Okavango)?’ <> ++
Cyril Taolo, acting deputy director of Botswana’s Wildlife Ministry, could also not explain why the ‘scavengers observed feeding on affected elephant carcasses’ ** are not dying as well.
The most controversial theories surround human-elephant conflict which has been adamantly denied by Cyril Taolo, acting deputy director of Botswana’s Wildlife Ministry or simply not addressed.
Taolo did not “…discuss the possibility that the Khama’s miffed by disarming of anti-poaching unit could have been involved in efforts to cause instability in Botswana. He also refused to discuss the possibility of agent provocateurs using substances like nerve gas to kill elephants in area.” **
“Popular sentiment in parts of the country has turned against elephants, however, as many blame them for the destruction of cropland.” The current President of Botswana, Mokgweetsi Masisi ran his campaign and was reelected, to some extent, on his vows “to keep elephants more in check”. ++
Masisi’s op-ed in WSJ June 2019 entitled “Hunting Elephants Will Help Them Survive They’re magnificent creatures, but Botswana has too many of them in the wrong places” left little doubt that he, unlike his predecessor former President Lt Gen Ian Khama, would reintroduce elephant hunting licenses, although a quota is said to be imposed.
Elephant biologist Keith Lindsay (with 40 years of experience, he served five years in the “Wildlife Ministry before Masisi came to power”) believes that the Botswana Okavango elephants were “targeted” ++ & that “neurotoxins available to farmers” should still be investigated. ++
Going forward, Cyril Taolo, acting deputy director of Botswana’s Wildlife Ministry, says his department does plan to regularly monitor “seasonal water-pans” (elephant watering holes) to include testing for “toxins produced … by cyanobacteria”
This won’t bring our 330 Okavango elephants back but could save the lives of many more.
ZIMBZBWE UPDATE: Meanwhile our Zimbabwe elephant death toll has climbed to 34 (12 additional African elephants have died between 24 August & 23 September 2020 in the area between Hwange National Park & Victoria Falls). Fulton Upenyu Mangwanya, Director of the Zimbabwe Parks and Wildlife Management Authority explained that “Tests conducted in Zimbabwe so far point to a disease called haemorrhagic septicaemia, which is caused by bacterial infection.”
Resources not linked:
# “Why are elephants dying? The race to solve the mystery of mass die-offs” The Guardian
<> “Botswana: Mystery elephant deaths caused by cyanobacteria” BBC News
++ “Botswana reveals the cause of a mass elephant die-off after months-long wait” By Mqondisi Dube & Max Bearak The Washington Post
** “Bots high elephant mortality attributed to neurological issues” by Sello Motseta The Tswana Times
Images: CC Flicker by stephenjjohnson Okavango Delta Botswana Africa elephants & elephant herd drinking from waterhole Okavango Delta Botswana Africa and by The Daily Mail elephant lays dead by water hole in Botswana killed by toxins in water called cyanobacteria