As the temperature rises in the Amazon, Amazonian dolphins are struggling to survive. Several hundred have died in and around lake Tefe where the temperature has reached 39 degrees Celsius – for reference, a hot bath is anything above 37 degrees (at 44 degrees, people start to scald).
Their bodies along with many thousands of fish, are floating on the surface. The lake is particularly hot, as a drought has led to much of the water drying up, allowing the remaining water to take the temperature of the air more quickly. While disease and sewage contamination are being checked, the hugely high temperature has a huge impact on the bodies of everything living in the water, so even if the eventual death is caused by something else, the heat would likely have killed the dolphins in the near future anyway.
Brazil is not the only country which is struggling in this way, it is happening world wide. It is true that the world has just left the El nino period, which always has higher temperatures, but still, many species like the Amazon dolphins (which is already endangered) cannot face this pressure for long, without being pushed far closer to extinction.