At least 350 elephants died under mysterious circumstances in Botswana in 2020, sparking global concerns while leaving scientists puzzled about the reason for the mortalities. Four years later, a study conducted at King’s College London may have finally unearthed the answer. As per the research, a “toxic brew” of open water tainted by a species of cyanobacteria that releases cyanotoxins, which contaminated the watering holes in the region, led to mass elephant deaths.

Combining satellite data and spatial analysis the study revealed that as many as 20 watering holes in the Okavango Delta had been contaminated across roughly 6,000 sq km. After drinking, elephants were estimated to have walked an average of 16.5 km from the toxic waterholes and died within about 88 hours of exposure.

“Our results highlight that seasonal, predominantly rain-fed pans, rather than the permanent waterbodies (i.e., lakes, rivers, and lagoons) within the Panhandle, were the likely source of cyanotoxin exposure,” said Davide Lomeo, the lead scientist of the study.

Notably, the dead elephants were of varying ages, with tusks intact which led to scientists ruling out death by poaching. Additionally, no carcasses of other wildlife or livestock species were observed at the time of one of the aerial surveys.

Also Read | ‘Tax Collector’ Elephant In Sri Lanka Goes Viral For Stopping Vehicles, Seeking Food

What promoted algae growth?

Not all cyanobacteria or blue-green algae is toxic but some cyanobacteria produce a type of deadly algal blooms (HABs) in standing water. As per the study, the shift from a dry 2019 (the driest year in decades in the region) to an extremely wet 2020, may have prompted the unprecedented algal growth due to the resuspension of significant amounts of sediments and nutrients from the ground.

“Scientists believe that the production of cyanotoxins is related to certain environmental triggers, for example, sudden rise in water temperature, nutrient loading, salinity,” said Mr Lomeo.

Scientists have warned that such incidents may become frequent in the future owing to climate change.

“Southern Africa is projected to become drier and hotter under climate changes, and as a result, waterholes across this region will likely be drier for more months of the year. Our findings point to the potential negative effects on water quantity and quality, and the catastrophic repercussions on animals, this could have.

The study underscores the severe ecological consequences of toxic algal accumulation while emphasising the critical need for water quality surveillance across water bodies, including the smallest ones.

Botswana has threatened to send 20,000 elephants to Germany amid a dispute over the import of hunting trophies. According to The Guardian, the dispute between the two countries began earlier this year when Germany’s environment ministry, citing concerns about poaching, suggested imposing stricter limits on the import of hunting trophies. Notably, Germany is the European Union’s (EU) chief importer of African elephant trophies, as per a 2021 report by the Humane Society International. A ban on the import of hunting trophies would only impoverish Botswana, President Mokgweetsi Masisi said on Tuesday. 

The African leader argued that conservation efforts have led to an explosion in the number of elephants and increased man-animal conflict. Hunting is an important means to keep them in check, Mr Masisi said, as per the outlet. 

Botswana, home to the world’s largest elephant population, banned trophy hunting in 2014 but lifted the restrictions in 2019 under pressure from local communities. Now, the country issues annual hunting quotas. 

On Tuesday, Mr Masisi said that in recent years elephant herds have been trampling people and destroying homes and crops. “It is very easy to sit in Berlin and have an opinion about our affairs in Botswana. We are paying the price for preserving these animals for the world,” he said.

Mr Maisi also said Germans should “live together with the animals, in the way you are trying to tell us to”. “This is not a joke,” he added. 

Also Read | Who Was Savannah Graziano? Kidnapped US Girl Shot Dead By Cops

Previously, Botswana had offered to send 8,000 elephants to Angola and 500 to Mozambique to deal with the “overpopulation”. Mr Masisi said he would “like to offer such a gift to Germany” and “not take no for an answer”.

The African leader went on to criticise the German government. “We want our elephants to roam freely. The German weather is bad enough for them,” he added. “If you like them so much, then please accept this gift from us,” he said. 

A spokesperson for the German environment ministry said Botswana had not raised any concerns with Germany on the matter. However, environment minister Steffi Lemke “signalled that she will accept Botswana’s invitation if an opportunity arises” to inspect wildlife protection, as per The Independent. 

Meanwhile, in March, Botswana had threatened to send 10,000 elephants to Hyde Park in London in protest against a potential UK ban on safari hunters importing trophies.