Over 100 dolphins dead in Amazon as water temperature nears 40 degrees Celsius

More than a hundred dolphins have been discovered lifeless in the Brazilian Amazon amid an historic drought and record-high water temperatures that in places have exceeded 39 degrees Celsius, CNN reports.

The dead dolphins were all found in Lake Tefé over the past seven days, according to the Mamirauá Institute, a research facility funded by the Brazilian Ministry of Science.

The institute said such a high number of deaths was unusual and suggested record-high lake temperatures and an historic drought in the Amazon may have been the cause.