Rat Health Care & Information

Temperament Issues

Issues of behaviour and temperament.

Behaviourists have argued for decades, philosophers for centuries over the relationship between nature and nurture. Temperament and personality traits seem to be determined by nature (genetic programming from parents, and instinctive behaviour), and modified by nurture (experiences and care received from birth). In rats (as in humans) the inherited ‘personality’ seems to be able to be modified in some ways (for instance rats born to tame parents can learn to fear human contact if their early experiences of humans are largely negative), but others may be fixed and regardless of handling and experiences will show themselves with time. I have broken down the subject into the main areas of rattie temperament that cause problems for their humans.

Dominance struggles amongst rats.

All rats living in groups of two or more will develop a hierarchy. The rat at the top of this hierarchy is the most dominant rat in the group, and is called the alpha rat. In a larger group there is usually a chain of command, where the alpha rat will have a second in command, who will often do much of the work for him. The temperaments of these two rats usually determine the levels of tranquillity or hostility within the colony. A good alpha will ‘rule’ almost unnoticed; no bullying tactics, just a quiet strength that steps in to sort out any problems within the colony when another rat acts above his station.  An alpha will often rely on his second in command to investigate new things for him (take the risks in new situations), and to keep the others in line. Lower ranking rats seem to find a security in a good alpha, and squabbles are few.

Problems occur most often when either the alpha or the second in command is a thug! Bullying tactics do not always need to be overt (fighting and wounding), but can be not allowing cage-mates access to food, or keeping them in hiding, perhaps is an igloo or tube. In this sort of situation there will often be frequent scuffles as the inferior rat is ‘seen off’, and lower ranking rats may not thrive, or may lose weight and condition.

All out war often occurs when a second in command is not happy with his status and is constantly challenging the alpha for position. This can occur even after months of peaceful rule, when perhaps age or illness threatens the strength of the alpha and his ability to maintain control.

Other behaviours such as power grooming (may result in barbering), and mating (between same sex pairs), can also be expressions of dominance.

If you have a cage where there are frequent squabbles, and rats are often nursing small bites and scratches, or you have rats in a group where one or two are thriving and the others are not, then it is important to watch the behaviour within the cage carefully. A very dominant alpha (a bully) is easy to spot because he will be the one who is out and about at feeding time while the others peep out from their hiding places! Or he will be the one doing the chasing whenever there is a scuffle. A second in command who is causing the problems is sometimes harder to spot, but with careful observation you should be able to work out where the problems lie.

Most problems with over dominance occur amongst males in the first year of their lives, though later on there may be issues as the balance of power changes. This type of over dominance is usually hormonally driven and mirrors levels of testosterone production in the young male. It seems to be at its peak in the second half of the first year. Things can become intolerable for the other rats in the colony (from their human’s point of view), and one of three courses of action is usually taken. The rat is removed from the colony and either lives alone, or is castrated and re-introduced (often to another group of girls). Or the rat is given Tardak which chemically mimics castration, and kept in the colony – the Tardak being used to get him through the worst period (particularly useful if the rat is older and getting towards the end of his natural testosterone surge).

Or the rat is castrated sooner rather than later and kept within the colony. Generally I now favour this third approach for rats where the cause of problems is almost certainly hormonal. 24 hours after castration the rat can be back in with his cage-mates, and is not forced into a solitary existence which can cause its own problems for later re-introductions. Generally the hormone levels then settle slowly over a period of weeks (even months) and a gradual change in behaviour occurs. Watch out though – the second in command will take on the role of the alpha… if he is also a bully the cycle begins again. That is why it is so important to observe behaviour carefully and try to make a correct assessment of the power structures within the cage before going ahead with surgery.  Also note that almost all colonies will have some scuffles as this is part of normal rattie behaviour. Don’t interfere unless the rats are being wounded, living in fear or being made to go without food.

A word about barbering

Barbering (power grooming, or over grooming - can be to another rat or oneself) is not, in itself, hurtful or dangerous, but can be very inconvenient – especially when show rats are barbered. This trait seems to have some genetic influence and it is best not to breed from rats that barber. In my experience the rats who I have known who have barbered (all does) have also all been very dominant.

Aggression towards other rats

Occasionally you will hear of a rat that doesn’t like other rats period! Even if castrated he will still resist any attempt to cage him with other rats either male or female.  This type of behaviour seems to be part of the rats genetic make up and such a rat is generally happy living alone, with plenty of human company.

Aggression towards humans

Aggression towards humans seems to be fairly uncommon in pet rats. To understand aggression in rats we must consider the things that might provoke a rat to bite a human. Then we can learn not to make ‘mistakes’ which are one of the main causes for being on the receiving end of a bite.

Fear and anxiety

Some rats will bite when they are extremely fearful or anxious. This is typically seen in a rat that has received little loving or gentle handling in the first couple of months of her life and is then homed into an eager pet home. The problem can often be exacerbated if the rat is homed alone. She will then live in a constant state of anxiety, and may be resistant to her human’s attempts to bring her out for a cuddle. She has little defence against the large grasping hand (that may be seen as the same as those who have handled her roughly in the past), and if she has nowhere left to run, she may feel forced to ‘attack’.

Pain and confusion

Like most animals when a rat is in severe pain, or is confused by its circumstances it may respond by biting by ‘mistake’. Never go to pick up a rat that has just been fighting, especially if injured, or a rat that is in pain or in threatening circumstances. Go in slowly, talking quietly, and with a towel, or gloves if that will prevent your own injury. Rats at shows in show tanks (especially older bucks on their first time out) can feel very confused and threatened. They are surrounded by the smell of other rats – may be pushed up close to strange bucks, and in an alien environment. No wonder sometimes judges get bitten! If a normally pleasant rat is stressed to the point of biting through the process of ‘showing’ then perhaps it would be better for him to stay at home.

Defending territory

Some rats will bite anything poked through the cage bars, others will lunge at a hand that comes into their nesting space.

‘Bad blood’

Of course some rats are just aggressive by nature but thankfully these seem to be few and far between. These rats will bite even when unprovoked, and often without warning. Their bites will usually be serious – not ‘nips’, because they are driven by aggression, and mean business. 

Dealing with fear and anxiety in rats

From experience I would say that young rats are best ‘tamed’ through excessive gentle handling (forced socialisation), while older rats may require more time and trust training to overcome their fear.

Forced socialisation is a technique developed by a rat rescuer in the USA, and is based on the an assumption (?fact) that rats cannot maintain their fear of you for over 20 minutes. The idea is to have the rat in contact with you constantly for at least 20 minutes after which period her fear will begin to subside. This should be done at least daily, and although the rat can move around on your body she should not be allowed to lose contact with you at all during this time. No fearful creature would want to be ‘imprisoned’ in your hands for such a length of time, but if allowed to sit on your shoulder, have a stroke on your lap or hide up your jumper the fear will soon subside. But do use your hands at times (to stroke, scritch, cuddle) so that she becomes used to the idea that hands bring comfort and pleasure (and treats).

Older rats (especially those who have had very bad experiences of humans) can be harder to tame. Often they need to be patiently trust trained through a series of steps (e.g. hands in cage, hands feeding treats, hands touching, walking onto hands, being picked up). This process can take weeks (even months), and sometimes cannot be hurried. It will also help to house the fearful rat with a very steady, friendly rat of the same sex, as they will lead by example.

Problems with introductions

Introductions will be easier or harder depending on the age and temperament of the rats concerned. With any introduction you have to allow for some expression of dominance, and some squeaking and fuss from the more submissive rat. The key is, knowing when enough is enough, and stepping in before the real trouble begins.

When introducing kittens to older rats it is always best to introduce them in pairs and over the age of about 7 weeks. I have noticed a big difference in how 6 and 7 week old kittens deal with the stresses of introductions, with the former finding the whole experience far more distressing, if there is any display of dominance against them. If a single kitten is being introduced to an established colony there should always be younger rats in the colony who will be willing to wrestle and play with the newcomer. With some variation because of temperament, the easiest introductions are kittens to other kittens, then kittens to adult does and bucks, then adult does to other adult does, with adult bucks being the hardest to introduce to each other. Castrated bucks are often easiest to introduce to does rather than bucks.

Some introductions will be quick and trouble free. If you know the temperament of the rats involved you may be able to predict what the result of their meeting will be. More difficult introductions often require time and patience. But all introductions follow the same basic pattern. Move from the least threatening situation for the rats towards the more threatening, at whatever speed seems right for them. Start off by introducing them in a neutral area; one where neither rat normally goes, but also one where it is easy for them to be comfortable and relaxed, where they won’t run off and escape, and where you can access them easily should trouble arise. Your knee is not neutral – it belongs to your rats! An armchair, bed or the like is ideal. Some folks use the bath – but just being in the bath can cause the rat to feel threatened, and may not be helpful in the process of introductions.

Let the rats meet each other and do the necessary sniffing, investigating and flipping. Watch for signs of aggression; the rat fluffing its coat out to look bigger, side-wards ‘pushing’ action against the body of the newcomer and standing up on hind legs in a ‘boxing’ manner. If you see these be ready to intervene – perhaps have a water spray handy so that you can spray the rats to break up any fighting. Best to end the session while everyone is still relatively friendly, and try again in a few hours. Don’t leave too long between sessions. 24 hours is a long time in the life of a rat.

The most threatening place is of course the cage – the place where there is no escape, and where one or more of the rats may feel a sense of ownership. Before the rats ever make it back into the cage together make sure that you scrub it thoroughly with washing up liquid and hot water. A cage cleaning spray may also be used to remove lingering smells. Re-arrange the cage furniture so that it isn’t familiar to anyone, and make sure that this is well cleaned too. Some people recommend rubbing all the rats involved with vanilla essence to make them all smell similar. A big bowl of some very appealing food may help too – but not if your rat is a food-guarder!

Introductions, and especially that first cage time usually involve some degree of ‘scuffles’, with some squeaking and squealing (especially does). Resist the urge to immediately remove the newcomer… but watch carefully and try to judge the rats behaviour, as to whether it is truly aggressive or not.

Article by Alison Campbell

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