Why Do Gerbils Puff Up?

If you, like so many others, love little furry animals, then you may have a gerbil in your home. They make great pets and, if their cage is kept clean, do not smell.

Gerbils communicate using their body language such as standing, chattering their teeth, or licking. Among the many methods, gerbils use to speak to one another is puffing up their fur.    

Why Do Gerbils Puff Up?

Gerbils puff up their fur to signal they are either going to fight or that they are not feeling well.  

It’s important to know when your little buddy is trying to tell you something is wrong. Read on to understand better the two reasons your gerbils might be puffing out their coat.

A Gerbil Puffs Up Because They are Ready to Fight

Keeping two or more gerbils in the same cage is not rare, and you may notice that your pets play fight from time to time. Play fighting among gerbils is normal and completely harmless. Luckily, a real gerbil fight is rare.

However, if your gerbils do begin to fight one another, they will show signs, such as being puffed up, before they do. There are some definitive signs that your gerbils are not just play fighting but are ready to embark on a dangerous melee.

Signs your gerbils are about to fight include:

  • Chasing. Gerbils will chase one another when they are playing, but this type of chasing is different. The aggressor will chase a subordinate gerbil quickly and strike the other animal in the rear.  
  • Biting. When gerbils are fighting, they will bite each other’s faces, tails, and rear ends. This behavior is much more vicious than nibbling or grooming each other. 
  • Chattering teeth. When a gerbil is highly aroused, they will chatter their teeth together to warn the others in the cage.  
  • Puffed up fur and arched backs.  In keeping with the theme of this article, gerbils will puff up their fur and arch their backs just before a sincere fight is about to begin.

If your gerbils exhibit any of these signs, it is time to interfere and remove and separate them into separate cages until they have cooled off. Unfortunately, it may be necessary to keep gerbils who have been fighting away from each other permanently.  

Puffing, a Sign Your Gerbil Is Not Feeling Well

Remaining observant of any changes in your gerbil’s appearance or behavior can mitigate many highly treatable health problems.  Gerbils will puff up their fur when they are feeling unwell, so watching for this sign is vital to the health of your pet. 

There are several illnesses your gerbil might be experiencing, including hypothermia, diarrhea, dehydration, mites, and poisoning. If you have any questions about the health of your gerbil, it is wise to call your veterinarian for advice. 


Hypothermia occurs when your gerbil is exposed to cold temperatures or after having become wet and remained that way for too long. Other symptoms that your pet might exhibit include huddling, not moving around as much as usual, and generally looking ill. To treat hypothermia, slowly warm up the gerbil with your body heat or a heating pad turned on low.


Gerbils will experience diarrhea after eating watery vegetables, fresh fruit, or too many greens. Make sure to limit how many greens you offer your gerbil and watch out for too many watery vegetables such as cucumbers, lettuce, and celery.  


If your gerbil experiences diarrhea, it is vital to watch them for signs of dehydration. Symptoms in the initial stages may not be noticeable. But as dehydration progresses, your gerbil can become irritable, sleepy, be puffed up, have dull and half-closed eyes.

To treat dehydration, give your gerbil drinks of water using an eyedropper or small syringe until they appear better. Always make sure your pet always has a fresh supply of water. 

There’s an important note to make about gerbil poop that you should check out in this article I wrote. 


Mites are parasites that can cause your pet to feel unwell and have an allergic reaction. To treat your gerbil and cage, spray the pen with mite spray many times over several weeks. On days you spray, replace all the gerbils bedding, toys, and food.  


Gerbils are susceptible to poisoning by household chemicals such as cleaners, pesticides, and flea powder. Some household plants can also poison your gerbil, including aloe and begonias.

If your gerbil is puffed up and shows signs of poisoning, there is little you can do. However, if you witness your pet running through a household chemical act quickly and rinse the animal with warm water.   

Watch out for what is poisonous to gerbils because this separate article may save their life. Please view it if you have a moment. 

Taking Good Care of Your Gerbil


Knowing what your gerbil is trying to tell you is important for your pet’s safety and well-being. Here are some other tips for giving your gerbil top-notch care. 

Match Your Gerbils Well

Gerbils that get along well love to sleep together in the same spot inside their cage. So, if your gerbils stop sleeping together, it is a sure sign they are not getting along well. To prevent fights and to encourage your gerbils to sleep together, try using only one nest box in the cage. This will force the gerbils to sleep next to each other, causing bonding and less of a likelihood they will fight.  

Know When It’s Time to See a Veterinarian

Gerbils, like humans, should have a full physical examination by a veterinarian that treats small mammals every six months. By having an examination, the veterinarian can detect problems, including any change in weight from one visit to the next. She can also check for parasites and give advice on how to maintain your gerbil’s health.   

Your Gerbil Likes to be Social

Yes, unlike hamsters, gerbils are very sociable animals, and living alone in a cage can is not good for them. Gerbils will live longer and healthier lives if they live with other gerbils. Solitary gerbils tend to be overweight, have shorter lifespans, and are unhealthy. It is best to bring home two or three gerbils from the same cage at the pet store. They will already have acclimated to each other and have formed a social bond.

Feed Your Gerbil a Healthy Diet

Pre-mixed gerbil food from the pet store, such as this one, is enough to keep your gerbil happily fed. However, you might also want to feed your gerbil fresh fruits and vegetables in lesser amounts. Gerbils also like hard-boiled eggs, peanuts, cheese, and sunflower seeds. A word of caution though, these items should only be given to your gerbil in tiny amounts because of their fat content. 

Give Your Gerbils a Safe Habitat

Since gerbils are chewers, you do not want to keep your gerbils in a cage made of wood. Wire cages do not work well either because gerbils dig, and the metal could harm them. The best cages for your gerbils are 20-gallon fish tanks or gerbil homes available at the pet store, such as this one.

Do not choose a round tank because gerbils like to curl up in corners. You can never have too much room in the cage for gerbils as they enjoy playing when they are not asleep.  

Know Your Gerbils Normal Activity Level

Unlike hamsters, gerbils are diurnal, meaning they are awake mainly in the daytime and sleep at night. 

Final Words

Gerbils make fine pets and will puff up their fur for a variety of reasons. As an alert pet owner, it’s important to take notice and look for signs of illness or that a fight is about to occur. That way, you can act on what you see and allow the animals to live together in safety. If you watch for the signs of trouble, your gerbil and you will enjoy many years of fun.


My name is Anna and I work full time in my local pet shop where we sell many animals that I write about on this site. I love all animals and love writing about them.