Satellite data analysis suggests climate-induced algal blooms could be behind hundreds of deaths in Botswana that sparked flurry of theories in 2020More than 350 elephants that died in mysterious circumstances probably drank toxic water, according to a new paper that warns of an "alarming trend" in climate-induced poisoning.The deaths in Botswana's Okavango delta were described by scientists as a "conservation disaster". Elephants of all ages were seen walking in circles before collapsing and dying. Carcasses were first spotted in north-eastern Botswana in May and June 2020, with many theories circulating about the cause of death, including cyanide poisoning or an unknown disease.