The mysterious case of Botswana’s elephant deaths
Dec 2024: latest update from King's College London Study
A new study led by King’s College London has provided additional evidence to support the findings that the massive elephant die-off in 2020 was a result of drinking from stagnant water holes (pans) where toxic algae populations had exploded due to climate change:
“The drastic changes in ecohydrological and climate conditions, particularly in the shift between 2019 (low rainfall and high temperatures) and 2020 (high rainfall and lower temperature), underscore the likelihood for altered water quality and increased harmful cyanobacteria bloom risks,” the researchers say in their findings published in the journal Science of The Total Environment.
“These environmental dynamics, occurring in tandem with the carcass spatial clustering, provide compelling evidence of water quality deterioration as a possible contributing factor in the mass die-off event.”
Close to 400 elephants found dead in Botswana
Across a thousand-square-mile area northeast of the Okavango Delta, hundreds of elephants have mysteriously died. The reason why still eludes the government, animal experts and the public alike. The deaths occurred over several months, and are thought to have begun in March 2020. The carcasses were first discovered by conservationists from Elephants Without Borders (EWB) during flights across the Okavango Panhandle in May and June. Their flights revealed a worrying 356 elephant carcasses, with the potential for that number to increase higher still. This confidential report was leaked to the media which has led to a huge amount of speculation around the reasoning for these deaths.
POACHING, CYANIDE,STARVATION… WHAT IS KILLING BOTSWANA'S ELEPHANTS?
Based on historic events of mass elephant deaths, the all too common and expected cause of death is, unfortunately, poaching. However, these elephants were all found with their ivory intact, thus ruling out the possibility of death due to ivory poaching. But why else would so many elephants die?
Could it have been poisoning? Cyanide poisoning has also historically been a cause of mass elephant deaths, a shocking method used by either poachers or more often local farmers as a retaliation to crop raiding by elephants on local farms. In this case however, Cyanide poisoning was ruled out as an unlikely cause of the deaths because the carcasses would have been found in a much smaller area, clumped together near the site where the poison was released. Cyanide would also cause deaths of other animals which too drank the water, which was not observed in this case. Rather, only elephant carcasses have been found, and scattered over a vast area.
Anthrax poisoning caused by a bacterium in the soil was also considered. The pictured elephant carcasses that have been released indicate that death was very sudden, where the elephants collapsed and died immediately, many falling on their chests (as opposed to lying down sick for some time). Diseases such as Anthrax can cause sudden death, however it was ruled out due to the results of soil and carcasses both testing negative, with no evidence of Anthrax found.
Natural death from starvation was reviewed but discounted as a viable cause since the country was in the dry season during the first reporting of these deaths and there would have been sufficient vegetation for the animals following good rains. In addition, many of the elephants who died were young and in their prime, and therefore least likely to die of starvation.
Dr Thouless, the head of research at Save the Elephants based in Kenya, believes that a naturally occurring disease is currently the mostly likely cause of death of the elephants. Elephant Endotheliotrophic Herpes Virus (EEHV) is a virus that has been observed most often in elephants held in captivity but also wild Asian elephants. Another natural disease considered is Encephalomyocarditisis, a cardio viral infection often transmitted by rodents and that causes a range of neurological symptoms. This is one of the more likely causes of death as the elephants were seen to be disorientated and wandering in circles before they died - potential symptoms of the virus. According to EWB, several elephants seemed to be weak and lethargic and some also showed signs of disorientation and difficulty walking.
WHY ARE THERE NO ANSWERS YET ABOUT THE CAUSE OF DEATHS?
Experts disagree regarding the extent to which the government is prioritizing this issue to publish answers. Mark Hiley, the director of rescue operations at National Park Rescue, a Britain-based non-profit organisation aimed at combating poaching in Africa, believes that the government should have answers for the public by now. Dr. Pieter Kat, from LionAid, states in an op-ed in the Journal of African Elephants that "The cause of death should have been a piece of cake to decipher, especially since fresh carcasses were available and samples were collected....This cannot be shuffled conveniently under a carpet woven of complacency and excuses."
Keith Lindsay, a conservation biologist believes that the delay between initial reports of the dying elephants and the government’s official confirmation is concerning and that they do not appear to be fully in control of the situation. However, the Botswana authorities stay adamant that they are investigating fully. Cyril Taolo, acting director of the Department ofWildlife and National Parks states "The fact that we are prepared to send samples to other laboratories should be evidence enough that we are transparent and have nothing to hide.”
Mmadi Reuben, the principal veterinary officer at Botswana’s Department of Wildlife and National Parks has a different opinion and believes that the government has responded “swiftly, adequately and responsibly”.
Conservationists expect answers soon as the preliminary testing from a laboratory in Zimbabwe has now been completed. The results of these tests will not be made available until the results from specialist labs in South Africa, Canada, Zimbabwe and the US are returned. Unfortunately, testing has been delayed due to movement restrictions as a result of the corona virus pandemic. According to Koboto, of the Environment Ministry, comparisons between the results from the different labs are necessary in order to conclusively determine the cause. The results, which we are still awaiting, will hopefully shed some light on this issue.
WHAT IS THE LATEST UPDATE ON THE BOTSWANA ELEPHANT DEATHS?
Cyril Taolo, acting director of the Department of Wildlife and National Parks states that, based on evidence and test results from other countries including the United States, they are able to rule out ivory poaching and have determined that it is highly unlikely that an infectious pathogen is the culprit.
So far, the Botswana government have received the results from bacterial detection and toxicology tests from Botswana and histopathology tests from South Africa. Their focus is on investigating a “ broader range of environmental factors, such as naturally produced toxins from bacteria found in the environment, such as water bodies”. Taolo states that determining the cause is “a game of elimination”. Their strategy involves testing the most likely, common causes and then investigating the less common ones. These results have to be verified and confirmed by the results from the different laboratories that have performed tests. At this time, we are still awaiting further test results from laboratories around the world, a process that is taking longer than usual due to movement restrictions as a result of the corona virus pandemic.
The elephant deaths are a distressing issue but according to Dr Thouless, the situation is not yet classified as a conservation crisis as the number of deaths are a small percentage of the 15-20 thousand elephants that live in the Okavango Panhandle. However, considering that elephants are a particularly vulnerable species, this unknown threat is concerning and deserves time and attention in order to unmask the silent killer of the Botswana Elephants.
Written by Michelle Pengilly
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