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A groundbreaking discovery has brought clarity to the mysterious mass deaths of African elephants. According to a new report by scientists, these fatal outbreaks may be more likely to occur due to the effects of the ongoing climate crisis.
Between August and November 2020, 35 African elephants died under puzzling circumstances in northwestern Zimbabwe. Eleven of them perished within a 24-hour period. Dr. Chris Foggin, a veterinarian at Victoria Falls Wildlife Trust in Zimbabwe and co-author of the study, expressed astonishment at the simultaneous deaths, calling it a unique occurrence in the region.
In neighboring northern Botswana, about 350 elephants also succumbed to a similar fate earlier that year, within a span of three months. Initially, officials and experts struggled to explain these die-offs, which affected Africa’s largest elephant population. Poaching, poisoning, and drought were all considered as potential causes.
However, researchers have now determined that a bacterial infection led to the deaths of the elephants. Samples taken from 15 deceased elephants in Zimbabwe revealed evidence of septicemia, or blood poisoning, caused by a little-known bacterium called Bisgaard taxon 45. The study, published in the journal Nature Communications, emphasized the impact of the dry season, which resulted in depleting food and water resources. As the elephants were forced to travel greater distances to search for sustenance, the extreme conditions created a conducive environment for the infection to spread.
The scientists believe that the combination of heat, drought, and high population density in the area contributed to the outbreak. They also warned that as the Earth continues to warm, resulting in more frequent and severe droughts, there is a higher likelihood of similar mortality events occurring in the future.
Although cyanobacterial neurotoxins were responsible for the elephant deaths in Botswana, no link has been established between the Zimbabwe and Botswana incidents.
An endangered species at risk
The African elephant is an iconic species facing immense pressure from poaching and habitat loss. Classified as endangered on the International Union for Conservation of Nature Red List, their population has dwindled from 144,000 to approximately 350,000 between 2007 and 2014. These losses continue at an estimated rate of 8% per year.
The Kavango–Zambezi Transfront
