Humans are not the only species negatively affected by increasingly hot and humid conditions. Intense heatwaves sometimes kill large numbers of wild animals. Eastern Australia’s giant fruit bats, known as flying-foxes, provide possibly the most dramatic illustration. In late 2018, two days of extreme heat in the far north of Queensland wiped out one third of Australia’s population of spectacled flying-foxes. The species is now red-listed as endangered.
Bat biologists have identified high humidity as a major risk factor for these mass mortality events.
In late 2020, South Africa saw its first documented heat-related mass mortality event involving wild birds. Air temperatures in the typically humid Phongolo Nature Reserve in northern KwaZulu-Natal exceeded 45°C, about 10°C higher than average conditions. Staff in the reserve started seeing dead and dying birds. Most of the victims were songbirds, which are known to be more sensitive to extreme heat than many other groups of birds.
