[Animals] Hundreds of elephants died in Africa in 2020, and we are getting closer to knowing why

[FNX Magokiler]

When hundreds of African savannah elephants fell dead in Botswana's Okavango Delta in 2020, conservationists were alarmed. As the death toll increased – from dozens in March to more than 350 animals in July – their concern grew, especially since no one knew what was happening.

Shortly after, the mystery worsened when 34 more of this endangered species died across the border in northwestern Zimbabwe in a three-week period, and one more was found in November.

"It was very fast," says Chris Foggin, a veterinarian with the Victoria Falls Wildlife Trust who examined the elephant carcasses in Zimbabwe. "That was the dramatic thing."

A sensitive area and many suspects
African savanna elephants in the five-nation Kavango-Zambezi Transfrontier Conservation Area, or KAZA, represent the majority of what remains of the species, says Steve Osofsky, director of the Cornell Wildlife Health Center in Ithaca, United States. . There are about 350,000 African savannah elephants left, and given the already significant set of threats to their survival, "a new disease could be what tips that last domino toward extinction," says Osofsky, who was not involved in the new investigation.

In September 2020, the Government of Botswana attributed the deaths of elephants in the Okavango Delta to the presence of cyanobacteria in the water the elephants drank.

 

 

Although without data to support this, scientists have questioned this conclusion. Meanwhile, bodies in Zimbabwe showed no signs that they had died from the toxic algae.

And so the cause of the death continued to elude experts. They ruled out poaching because the tusks were intact and no gunshot wounds were found. Poisoning was unlikely because it did not affect other animals, such as the vultures that fed on the corpses.

Now, new research published recently in Nature Communications points to a different culprit, at least in the case of Zimbabwean elephants: a bacteria not previously found in elephants of any species, called Bisgaard's taxon 45, that causes a massive systemic infection. of the blood called septicemia.

Bisgaard's taxon 45 is related to another bacteria, called Pasteurella multocida, which can cause septicemia in livestock and was linked to the deaths of 200,000 endangered saiga antelopes in Kazakhstan in 2015. However, while it shares many of the same lethal genes, Bisgaard's taxon 45 is a separate species.

"It's a disease that we know can kill a reasonable number of elephants in a short period of time," says Foggin, co-leader of the study. And "it has the potential to kill many more under the right circumstances."

 

https://www.nationalgeographic.es/animales/2023/12/cientos-elefantes-africanos-muertos-2020-misterio-causas-cerca-resolverse