How do animals cope with extreme heat?

In cases of extreme heat, keepers look for physical signs an animal is not responding to heat, such as excessive panting or lethargy, and take appropriate measures to cool the animal down if such symptoms are observed. Many animals at the Zoo live in temperature-controlled indoor environments that provide refuge from the heat. All of the Zoo’s outdoor exhibits have cool indoor holding areas and hiding spaces that the animals can choose to enter whenever they want. For the animals who do choose to stay outdoors in hot weather, Zoo staff provide plenty of choices that allow the animals to choose the best ways to stay comfortable. Trees, bushes, and shade structures are features in many habitats, and all exhibit areas have cool water for the animals to stay hydrated. Large carnivores, such as Andean bears and tigers, are presented with ice blocks filled with frozen chunks of meat. Herbivores like the Western lowland gorillas and Asian elephants are offered vegetarian fruitsicles, which are ice cakes filled with frozen fruit and diluted fruit juice. Animals from temperate regions, like the Bird House’s turkeys and sandhill cranes, have outdoor habitats that are designed with species-appropriate ways to stay cool, like freshwater pools or wallows. Many of our animals, such as the alpacas at Kids’ Farm, enjoy being gently sprayed with sprinklers, misters, and hoses. Animals from tropical regions, like the clouded leopards or sloth bears, are acclimated to the heat...although many of them choose to spend the hottest part of the day taking a snooze.

When animals change the way they act to stay cooler or become warmer, scientists call this thermal regulatory behavior. During heat waves, this can include staying in the shade, entering the water or resting more. One way koalas in Australia cope with extreme heat is to hug cool tree trunks. Bears in California sometimes take a more unconventional approach, with videos showing them taking dips in people's pools when temperatures soar. Many animals go into the water more often to cool down during heatwaves. Even if the heat doesn't kill the wildlife, it can change their behavior in ways that influence the population size. Perhaps because they're more dehydrated or they can't be active enough because it's too hot, they don't breed that year. A 2023 study found that burying beetles were less likely to reproduce successfully when a heatwave hits during mating.