May 9, 2018, 3:33 p.m.View more articles
Most animals go to the toilet every day. Have you ever wondered what happens when they hibernate?
What’s the longest time that you’ve gone without going to the bathroom? Probably no more than a few hours, right? Well, meet the wood frog. This little animal can go for more than half a year without peeing. It does this when it goes into hibernation.
Hibernation is a bit like a deep sleep that some animals have during the winter. Food can be difficult to find in colder months, and hibernation helps the animal to survive without much food at all. Some animals don’t eat anything for months!
If the animal wants to survive without food, it has to use as little energy as possible. It settles down into a deep sleep, and its heart rate and breathing rate slow down. Its body temperature can also become much lower.
Some animals, like dormice, wake up for short periods of time during hibernation. This is so that they can stretch their muscles, pee, and poo. They don’t need to pee or poo very often because they aren’t eating as much food as they normally do. They’re mostly surviving by using the energy stored in their body fat. Using this energy produces a small amount of waste, and it’s important for the animal to get rid of this. If they don’t, waste can build up, and eventually become harmful to the animal.
One waste product that normally leaves the body in pee is called urea. Just like other waste products, urea can be harmful if it builds up in an animal’s body. So it might seem a bit odd that the wood frog’s body produces more urea than normal while it hibernates, even though it can’t pee! However, urea is actually really useful to wood frogs over the winter. Their bodies are able to recycle this waste product into something that keeps them alive.
When the wood frog hibernates, its body temperature can drop to as low as −18°C. Its blood and organs freeze, and its skin becomes frosty. Being this cold would kill most animals, but not the wood frog. Its body has special bacteria that recycle the urea. The urea protects all of the cells in the body as they freeze and stay frozen for six months or more.
This means that when the spring arrives six months later, the wood frog becomes unfrozen, and carries on with its life!
Watch Migration: Seasons to learn about another way that the changing seasons affect animals!