Record-breaking heat in the Washington, D.C. area has prompted the Smithsonian’s National Zoo to implement various measures aimed at keeping its animals comfortable and safe. With temperatures exceeding 100 degrees Fahrenheit last week, zookeepers intensified efforts to help animals cool off through a combination of environmental adjustments and specially prepared treats.
The zoo’s five-month-old baby elephant, Linh Mai, has been spending much of her time swimming and resting by the poolside. Staff have been conducting supervised excursions into a deeper outdoor pool, allowing her to familiarize herself with swimming independently, separate from adult elephants. In addition to pool time, Linh Mai receives daily bubble baths to aid in cooling.
Other species are also benefiting from tailored cooling methods. Large carnivores such as tigers and lions are given “bloodsicles” — frozen treats made from blood sometimes combined with bones or meat chunks. Elephants, gorillas, and pandas receive fruit-based frozen snacks called fruitsicles, while seals and sea lions enjoy fish encased in ice blocks. Swamp monkeys, known for their swimming ability, actively take dips in their pools to regulate body temperature.
Enrichment activities have been adapted to serve dual purposes of entertainment and cooling. Otters search for hidden snacks inside buckets filled with ice, providing both mental stimulation and relief from heat. Lemurs forage for diluted fruit juice from specially designed feeders, mimicking their natural nectar-feeding behavior by using their narrow snouts and long tongues.
Birds at the facility utilize various natural strategies to manage heat. Flamingos and ibises rely on thermoregulation through blood circulation in their long, featherless legs, which dissipate heat. Wading in water enhances this cooling effect. Interestingly, black-crowned night herons employ urohidrosis, a process by which they defecate on their legs; as the moisture evaporates, it cools their skin despite the unpleasantness.
For animals that prefer less activity during hot conditions, such as bobcats, lynx, and clouded leopards, enclosures provide ample shaded areas to rest out of direct sunlight. Zoo staff closely monitor the animals for signs of heat stress, including excessive panting or lethargy, and will move them indoors if needed.
Young, vulnerable animals receive particular care amid extreme heat. The zoo’s two sloth bear cubs, though native to hot South Asian climates, are kept indoors when temperatures reach 111 degrees to prevent overheating due to their age and developmental needs.
Zoo officials emphasize that the health and comfort of the animals remain a top priority as they adapt routines and environments to cope with the ongoing heatwave.