Welfare of Animals in Heat Waves Under Climate Change

Increasing frequency and intensity of heat waves under climate change is causing mass mortality events in wild animals and welfare crises in farm and companion animals globally.

Key Facts

The 2022 European heat wave killed an estimated 1 billion marine animals and caused mass bat mortality
Broiler chickens experience acute heat stress at temperatures above 30 degrees Celsius, a threshold increasingly exceeded in summer
Companion animals left in vehicles during heat waves die from hyperthermia within minutes
Flying foxes in Australia have suffered mass mortality events from heat waves, with thousands dying in single events
Heat wave mortality in wildlife tends to disproportionately affect juveniles and elderly individuals

Welfare Considerations

Climate change is transforming heat waves from occasional extreme events into regular features of the climate calendar — and wild and farmed animals are dying in enormous numbers as a result. Flying foxes falling dead from trees. Broiler chickens dying in sheds without cooling. Companion animals in hot vehicles. Marine animals experiencing thermal shock. The welfare implications of climate change are vast, diffuse, and growing. Reducing greenhouse gas emissions is, at its root, one of the most significant animal welfare actions available to humanity.

What You Can Do

Take climate action through consumption choices, advocacy, and voting to reduce animal welfare harms from heat waves
Provide water and shade for wildlife during heat waves — put out bowls in gardens and on balconies
Never leave companion animals in vehicles during warm weather
Advocate for heat stress welfare standards for farm animals that reflect the current and future climate