Here are some of the questions I get asked most frequently concerning rat behaviour.
Why are my rat's ears vibrating?
When female rats are in season, they will often vibrate their ears. This can be so fast that it can make their ears look like a blur! But don't worry, this is perfectly normal, and is just a female rat's way of saying 'come and get it, boys!'
My rats eyes almost popped out of his head! Does he need to see a vet?
Nope. This is called 'boggling', and again, is perfectly normal and nothing to worry about.
Boggling in rats is a sign of happiness. When a rat is happy, it will grind its teeth, and this causes a muscle behind the eye to push the eyeballs outward. It can look strange if you don't know what it is, and can really look like the rat is having some kind of seizure! Rats will grind their teeth together at the same time as boggling, which makes a soft 'chh-chh' sound as is known as 'bruxing'. But not all teeth grinding is a sign on contentment; rats also grind their teeth when angry or stressed, but this tends to be a much louder, sharper, cracking sound as opposed to the softer, quieter bruxing. Over time, you should learn the difference between the two.
My two girl rats are humping one another, does this mean they're gay?
In all likelyhood, no.
Rats hump one another for several reasons. Females will often mount and hump each other when they're in season, and males will commonly hump one another to show dominance, or just when they're over excited.
It is not at all unusual for me to see the lowest ranking rat in my group being forcibly humped by the higher-ups! At worst, it's just a little embarassing if the vicar is over for tea, but its quite normal.
One of my rats died in her cage, and the other rats started eating her! Is this normal?
Completely normal, Im afraid.
Rats in the wild cannot have dead bodies lying around their home as that would attract predators. They need to dispose of the body somehow, and the only way they can do this is to eat it. Some pet rats retain this instinct, but not all.
If you have not removed your rat's body from the cage within a reasonable amount of time, you may find the other rats begin to eat it. Disgusting as this may be to us, it makes perfect sense from their point of view.
My rat weaves his head from side to side, whats wrong with him?
He has poor eyesight.
Head weaving is commonly seen in rats with pink or ruby eyes, but it can occur in black eyed rats too. It is a sign that the rat has poor vision. Weaving and bobbing the head helps with the rat's depth perception. To get an idea of how this works for yourself, focus your eyes on an object in front of you. If you move your head from side to side, you see that the object appears to remain stationary, but everything else moves around it, which gives you an idea of how big the object is, how far away it is, and where it is in relation to other objects.
My rat was wagging his tail, what does this mean?
This is a bit of mystery, and the reason for it has never been conclusively proven. My personal opinion, based on observations of rats over the years, is that tail wagging indicates an extreme of emotion of some kind. Just as tail wagging in dogs does not automatically indicate happiness (dogs also wag their tails when in prey drive, when angry, or facing off to another dog) I suspect the same is true of rats. I've seen rats tail wag when they are completely happy, and also when they are clearly stressed out or scared, so that would seem to suggest its simply a sign of extreme emotional arousal. Not all rats tail wag, and it has been the minority of mine that do this. I had one boy who did it when he first arrived as he was very nervous and feared handling, so he'd wag his tail when touched. After a few weeks of getting used to contact, the behaviour stopped and he never did it again.
My rat wees everywhere! Is it true they have no bladder control?
Nope, this is a myth started by exterminators who wanted to scaremonger people into killing more rats. They spread the lie that rats have no bladder control, or even that rats don't possess a bladder at all (they do, but they do not possess a gall bladder, perhaps this is part of the confusion). Rats actually have fairly good bladder control; many rats will hold it in if they're with their owner, and only go when they're placed back in their cage.
What your rat is probably doing is scent marking, not actually weeing. When rats wee, you know about it because there tends to be a lot of it! But some rats (not all) will leave tiny drops of urine behind them as they walk. This serves two purposes: the first is to tell any other rats that this is their territory and to stay out. The second is so they can find their way back to safety by following the trails.
Some rats can, and will, mark everything they want to claim as theirs, or retrace their steps over, and this will include you.
I really don't think its a big deal, but some people might. Its worth realising that both bucks and does can do this, but it tends to be more common in bucks, particularly the more dominant individuals. Neutering a male can lessen or stop this, but that is not guaranteed either as some neutered boys still mark.
If it is an issue for you, I'd reccomend either wearing old clothes when handling the rat, or just getting used to it! It comes as part of the package when owning rats.
My rat has orange skin. Is this normal?
Yes. Some rats, particularly dominant males, will have orange grease on their skin. This is usually called 'buck grease' and is natural for rats. It doesn't cause any issues.
My rat is rubbing himself along the ground/sides of his cage. What is he doing?
He is scent marking. Rats have scent glands along their sides which they use to mark their territory. Some rats will rub themselves along things, like cats do, to spread this scent around. You may also see greasy patches on their flank from these glands, and the rat may scratch at these glands. In my experience, extreme bouts of side rubbing/gland scratching can indicate excessive hormones and the potential for the rat to behave aggressively to others. I almost always see this in rats that end up with hormonal aggression issues so I tend to keep an eye on rats who behave this way regularly.
One rat is always nibbling on the other one, and makes him squeak, is he hurting him?
No. They're grooming each other, and this is a normal part of rat social behaviour.
Rats cement bonds within the group by social grooming, much like monkeys do. When one rat grooms another so hard he squeaks, its called 'power grooming'. Its usually a way for the groomer to let the other rat know his place within the group. Think of it as the rat saying 'I accept you into my group, so I'll groom you. But I want to make sure you know your place, so I'll groom you hard'. Some rats will squeak when this takes place, but it doesn't really hurt them and they should be left to get on with it; its their social structure at work.
My rat has lost the fur on her front legs/lost her whiskers!
In this event, its likely that you have a barberer in your group. Barbering is the term for when a rat nibbles the fur or whiskers off another rat. The cause of this is generally unknown but could have a genetic basis. It may also be tied to emotional trauma or boredom.
Some rats will also 'self barber', where they bite off their own fur. You'll usually see evidence of this on their front legs. I have owned a rat who self barbered as he'd been kept in solitary confinement and was bored and lonely. Once he came here and got some companions, the behaviour stopped.
Barbering doesn't cause any problems, and there isn't much you can do to stop it. The only time it could be an issue is when you want to show your rats! But if you're not showing, then there is no problem allowing it to continue; you'll just have to put up with a bald rat!
Also be aware that sometimes sudden bald patches on a rat can indicate a staph infection. This usually runs its course and disappears in time without causing any issues. But if it persists, you can bathe the rat in hibiscrub and this often helps.
My rat nips my fingers if I put them through the bars; why is this and can I stop it?
This isn't an uncommon behaviour, but often it is something we as owners have encouraged. A big reason rats will bite through the bars is if they have been fed or given treats through the bars. It doesn't take a rat long to learn that things poking into the cage are usually food, and a lot of them will grab first and ask questions later! Given that rats also have poor eyesight, you can see why these misunderstandings occur. Most rats will let go as soon as they realise they've bitten a finger rather than a treat, and it is not actually aggression; just a mistake.
You can prevent this behaviour by ensuring you never feed your rat treats through the bars. Do not train them to think that anything that pokes through the bars might be food, and you shouldn't have an issue.