Sounds and Noises
Guinea pigs have very poor eyesight, and instead rely on their other senses to communicate with one another and to voice their emotions. One of the main ways they do this is by taking advantage of their excellent hearing and vocal abilities, essentially 'talking' to one another, and to their owners. By understanding the various different guinea pig sounds and what they mean, you will be able to figure out exactly what your cavy needs.
People have different names for each sound, so I've decided to organise them according to the emotion your pig is trying to express, or what they want. Over time you'll come to know your pets' individual noises, and by paying attention to their body language as well, you'll be able to figure out what they are trying to say.
Enjoyment or Pleasure
When guinea pigs are happy they tend to make a soft 'purring' sound, a bit like a cat. This shows that they are content and are enjoying themselves. It is particularly common when you are petting or stroking your cavy, and is a wonderful sign of affection. You will also notice them making this noise when you give them a treat, or if they are happily scampering around exploring. You may find that your piggy becomes more physically relaxed when showing pleasure as well, just as humans do.
When two guinea pigs are eyeing each other up, they will make gentle 'cooing' sounds to one another. This noise is similar to the 'purring' noise they make when they are happy, but is slightly deeper, and is often accompanied by a vibrating sensation. Male guinea pigs (boars) tend to make this sound more that females (sows), and you may also see them doing a 'mating dance' which involves circling the sow while gently swaying from side to side.
This is a very strange phenomenon, and one that isn't fully understood. From time to time you may find that your guinea pig tilts its head back and begins to make a noise that sounds just like a bird singing. Nobody really knows why they do this - sometimes it appears to happen when they have been surprised, but other times they seem to do it for no reason whatsoever! It can last from just a few seconds to a minute, and is beautiful to behold. Other guinea pigs can respond in different ways - some will stand still and listen, while others will be terrified, and run around the cage trying to escape it. If you see this happening, you should remove the singing cavy until it stops.
Calling for Attention
Although they are mostly quite undemanding animals, when guinea pigs want something they will make a high pitched 'squeaking' noise. Young pups will make this sound to get their mother's attention, for example if they are hungry. As they get older, your cavies will also make this sound to get your attention. They can become particularly vocal when they know that it is meal time, or if they hear you rustling in the cupboard where their food is kept! More often than not, this sound means 'feed me!'
Unhappy or Disturbed
This happens particularly when a guinea pig is trying to get some sleep, or just wants to spend some time alone. If another pig disturbs it, or you try to pick it up, it will make a quiet 'moaning' noise, just like you would if someone disturbed your sleep. If they continue to be disturbed, they will get louder and louder with their complaining. As long as they are left alone they will just go back to whatever they were doing, but if they continue to be disturbed they may become slightly aggressive, and headbutt or kick whoever is annoying them. It's best to leave your cavies alone when they are like this; they'll soon be refreshed and eager to play again!
Anger or Aggression
When guinea pigs are angered, they chatter their teeth together rapidly. This acts as a warning to humans and other cavies that they should stay away. This noise is particularly common when two pigs meet each other for the first time. Boars in particular will chatter their teeth to establish who is the dominant male. If the chattering continues, you may notice the fur on the backs of their necks stand up to make themselves appear bigger, and they may also start to rock from side to side. When you hear teeth chattering, it is best to separate the pigs before they begin to fight. Watch your fingers when doing so as they may bite you.
Fright or Pain
If you hear a high pitched 'squeal' or 'shriek' it means that your cavy is either frightened or in pain. This can often be in response to a loud noise, or if they get nipped by a cagemate. Guinea pigs also make this sound when another pig is being aggressive towards them. When they do so, they are telling the aggressive animal that they don't want to get into a fight, and just want to be left alone.
Sometimes, a guinea pig may stand completely still and go utterly silent. This is a sign that they are very scared of something and need help immediately. If the cause of their terror is obvious, for example if you have just turned on the vacuum cleaner, then turn it off immediately. You can help to calm your pet by gently talking to it, or by petting and stroking it. Be careful though, as they may bite in response to their fear.
The above guide will help you to figure out what your guinea pig's sounds mean, so that you can have a better understanding of these wonderful creatures, and so that you can respond to their needs in the proper way.