Domestic cat maternal aggression is also referred to as maternal protective aggression. It’s what you think it is: a queen’s protective behaviour towards perceived threats to her kittens. It’s a natural instinct when she is caring for her young.
In Peter Neville’s book Do Cats Need Shrinks? a client of his, Susan Swift, asked for his help because, Lucy, her Birman queen, produced a litter and she became particularly aggressive towards Susan and her family. She wouldn’t let the family near her kittens even to the point where she appeared not to recognise them. She would attack them when they walked past without any interference in her parenting.
This was perhaps an extreme version of domestic cat maternal aggression but of course it varies between cats. This behaviour can manifest itself in different ways and to different extents from defensive posturing and sounds to actual physical attacks as described.
Typical aggressive behaviours would include biting, clawing, swatting, growling and hissing. Some queens are more assertive than others, who might be quite mild in their defensive behaviours.
And as can be seen in Susan’s story, the behaviour can be triggered with very mild interventions but once again it depends upon the cat as to what kind of stimulus triggers it. Normally it would be approaching her kittens or perhaps unfamiliar smells or even a sudden movement near the nesting area.
This is a temporary behaviour during the early stages of the kittens’ lives. As they grow older and become more dependent her protective aggression diminishes.
The advice, as you can expect, is to allow her some space during this time and avoid disturbances when possible. People should respect the mother’s need for privacy and provide a quiet and secure environment which would reduce the likelihood of maternal aggression.
Neville, in respect of Susan’s problem, says that, “The majority of female cats don’t defend their kittens to such a degree as Lucy, but when they do it can be one of the most pronounced types of aggression, we are likely to encounter.”
Some females will allow people to approach and intervene in the nest area but others might feel challenged. The female might want to run as part of the flight and fight response but they have to mute the flight response and defend their kittens. This can lead to a pent-up emotion which can suddenly explode.
Neville mentions Dr. Benjamin Hart in California, one of the founders of animal behaviour therapy, who has suggested that the added aggression might be due to a fall in the level of progesterone hormone at the moment of birth.
During pregnancy, the female produces this hormone in large quantities to help her body cope with the physiological changes involved. The hormone has a calming influence on the area of the brain controlling emotions. With this hormone gone the queen may become highly reactive and easily provoked into an emotional, defensive reaction. A veterinarian might suggest administering artificial progesterone (progestins) as a treatment but other than that the suggestions above would be the way to minimize the behaviour.
In humans, the hormone progesterone is implicated in some mothers suffering from post-natal depression.
