Hippos are large African mammals with a bad reputation for being dangerous. I saw many hippos on safari in Africa, but they were always in the water. I asked the guide why and the answer surprised me.
Hippos spend a lot of time in the water to cool down and stay out of the sun. Due to their large size, they cannot regulate their temperature as smaller mammals do. Their skin has no fur or hair, which leaves them susceptible to sunburn and heatstroke.
Please read on if you want to know more about why hippos spend so much time in the water.
Why do hippos enjoy water?
Hippopotamuses spend most of their time in shallow rivers and lakes but are never too far from the land where they can forage for plants, fruits, and berries.
Hippos can get around easier when in the water, although they can run up to 48 km/h on land. However, hippos’ biggest reason to remain submerged in water is to protect their sensitive skin from the sun’s harsh rays.
If you have ever been to Africa, you will know how intense the sun can be, but even if you haven’t, you probably know how uncomfortable you can be on a hot day.
Because hippos don’t have hair or fur, and because of their large size, their skin is exposed to the sun more than most African animals. The sun and the heat make it dangerous for them to stay out of the water for too long.
If you wonder why evolution hasn’t provided hippos with fur, the lack of hair helps them stay insulated while underwater. This allows them to get around easier while in the water and helps them avoid predators and hunters.
Hippos can move extremely fast in the water, using only a quarter of the energy they need to use on land. Hippos do not swim the same as most animals but will propel themselves forward off the bottom of the lake. By doing this, hippos can get around underwater fast and often surprise an unsuspecting kayak or boat.
Hippos prefer walking in shallower lakes and ponds where they can walk across the mud, but they will propel themselves forward with significant momentum in emergencies.
If you have ever seen a hippo in a zoo and have a glass window next to where they swim, you may have seen this. The video below shows the way that hippos ‘swim.’
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Can hippos survive without water?
Hippos are mammals and therefore can not survive without drinking or ingesting water. However, hippos also need water to shield their bodies from the sun’s harsh rays in the African climate.
When hippos are out of the water for extended periods, their bodies naturally secrete a red, oily substance that acts as a natural sunscreen, giving them a little extra time to find a better spot to submerge themselves. This is called blood sweat, although it is not either. This is made up of Hipposudoric acid.
When the hippo gets out of the water, it can cool down its body temperature by sweating. However, hippos do not have a thermoregulation system that works like smaller animals because of their huge size. This makes it hard for them to regulate their body temperatures.
As a result, when the hippo is out of water for about 3 hours or longer, they can suffer the effects of heatstroke. This is why hippos spend so much time in the water rather than using other means of cooling down. Because of this, hippos cannot use the shade of the trees as a refuge from the heat during hot periods.
Because of their slow metabolism when resting in water, hippos do not need as much food as they would on land. Hippos do not feed in the water, although they can readily consume up to 2% of their weight each day on land. This converts to about 88 pounds of food roughly per day.
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Do hippos come out of the water?
Hippos generally do not come out of the water during the day unless they are disturbed or are looking for somewhere to sleep. They like to rest half-submerged in water during the day and then look for a place to sleep on land near the river.
Hippos have a very good sense of smell and are very sensitive to scent. If a hippo feels that there is danger nearby, then it will usually come out of the water and make lots of noise to scare away any predator. However, a hungry hippo can be very dangerous when it comes out at night or in the early morning as it wants to eat something quickly before it goes back into the water.
Do you know what hippos eat? Find out here
How long do hippos stay out of the water?
The amount of time a hippo stays out of the water depends on the temperature and food availability. When it is cold and there is lots of food around, they are less likely to come out, so they do not need to use their energy reserves to warm up again. In contrast, in hot weather with little food available, they will have no trouble floating on the surface for many hours.
During particularly hot periods, hippos can lose as much as 7 litres of water per hour during daylight when they are out on land. However, they only lose about 2 litres per hour when they are submerged. When a hippo is out of the water, it can be very dangerous as it will usually approach humans more than its instinct would suggest.
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Can hippos swim?
Hippos do not swim but propel themselves forward with their powerful legs. They can do this at speeds of between 5 and 10 kilometres per hour, depending on the type of water they are currently in. However, the hippo is not particularly fast over long distances but can cover a lot of ground in a short amount of time.
It might seem as though the hippo spends most of its time underwater during the dry season. It spends about three-quarters of its time on land looking for something to eat during this period, such as roots, grasses, or fruit.
Hippos are the most dangerous animals in Africa. Find out why in this article I wrote.