What animal drinks the most water in one sitting?

While every effort has been made to follow citation style rules, there may be some discrepancies. Please refer to the appropriate style manual or other sources if you have any questions.

Camels have long been known for their ability to go weeks at a time without needing to drink water—an ability that makes them particularly useful pack animals for people traveling across arid environments and that earned them the nickname “ships of the desert.” Camels are also known for their prominent humps (either one or two humps, depending on the species), which leads many people to believe that these are used to store water for access at a later time. However, camels’ humps actually store fatty tissue, not water, which is used as a source of nourishment when food is scarce.

What do camels store in their humps?

Learn more about camels and their humps.

So why do camels store fat in these humps instead of having it spread equally throughout their bodies, like other mammals? Camels typically live in the desert, where food sources can be hard to come by. When a camel is unable to access food for a long period of time, its body is able to metabolize the fat in the humps for nutrition. The humps can deflate and droop if the camel has gone a particularly long time without food, but they will sit upright again once the camel is able to refuel. The camel’s humps also help the animal regulate its body temperature, an important feature in the desert, where temperatures can be extremely high during the day and drop drastically at night. By concentrating fatty tissue in humps on their backs, camels are able to minimize heat insulation throughout the rest of their body during the day when the temperature is high, and their body temperature rises. Then, at night, the extra heat dissipates through the rest of the camel’s body so that their body temperature is not too low when the temperature is cooler.

Although the humps do not store water, camels are still incredibly efficient in the amount of water they use per day, which is why they are able to go nearly a week without drinking. This is partly due to the unique shape of their blood cells, which are oval. Oval-shaped blood cells allow camels to consume large amounts of water (up to 30 gallons in one sitting!) since the cells are more elastic and can change shape more easily. This shape also allows their blood to flow more easily when water is scarce, which is common in a desert.

A camel’s humps are incredibly important for the animal’s survival in a tough environment like a desert. Without its humps, a camel would be more likely to overheat and sweat—but it’s still the oval-shaped blood cells that help the camel retain so much water, not the humps.

Desert-dwelling prairie rattlesnakes of the western U.S. are ultimate survivors, able to get by on just one hearty meal a year. But without a sip of water now and then, the snakes would shrivel up and hiss their last.

So how do these sit-and-wait predators stay hydrated way up in the Rocky Mountains, where standing water is scarce? Easy. They turn their bodies into rain-collecting bowls.

When it sprinkles, prairie rattlesnakes slither out in the open and coil up, says Emily Taylor, a snake biologist and director of the Physiological Ecology of Reptiles Laboratory, at California Polytechnic State University, in San Luis Obispo. With their bodies flattened into a disk, the rain beads up on their scales thanks to a microscopic, labyrinth-like texture that prevent the droplets from sliding off.

In 2017, Taylor and her colleague Scott Boback, of Dickinson College, in Pennsylvania, placed time-lapse cameras near wild rattlesnake nurseries in Colorado as part of a citizen science initiative called Project RattleCam. The images revealed that baby rattlesnakes assume the flattened position the day after they’re born. (Read how rattlesnakes have “friends.”)

“So they’re born thirsty, and they’re born with this instinct to do the rain-harvesting behavior,” Taylor says.

Watch rattlesnakes coil into bowls

Of course, most animals can’t turn their bodies into a bowl at a moment’s notice. Here’s how some other creatures quench their thirst.

FREE BONUS ISSUE

SUBSCRIBE

Thorny devils tap water with their skin

In Australia’s outback lives a lizard that looks more like a cactus. Known as thorny devils, these animals specialize in eating ants, which is also where they get a lot of their hydration.

But when ants are scarce, or conditions are even drier than normal, the reptiles have a backup. A network of tiny canals on their spiky skin catches small amounts of water and guides the liquid directly to their mouth. 

What’s more, the devils can use the same trick to leech liquid out of moist sand after a rain or heavy dew. All they do is kick the sand up onto their back and let their skin do the rest.

An ocean away in southwestern Africa, the Namib desert beetle pulls off a similar feat.