In their natural state, once kittens are a few days old, the mother may move them to a different nest site. Many mothers move their litters from the nest and will probably do it at least once before her kittens are weaned.
Despite the fact that scientists are yet to be completely sure as to why mother cats do this, the obvious reason is to ensure that their kittens are safe when, for example, there may be a disturbance near the nest which makes the mother uncomfortable about remaining there.
Another reason put forward by a well-known author1 is that cats in the wild move their kittens from the original den to minimise the risk of a flea infestation.
In the wild, it is probably reasonable to state that every kitten will carry some cat fleas, at the very least, and there may very well be an infestation in the den because of the congregation of kittens and mother there. Also, the mother has to spend so much time in the nest, flea eggs may accumulate and when these eggs turn into adult fleas all they have to do is jump onto a kitten who happens to be on the spot.
Moving all the kittens away from a flea infested nest makes common sense in helping to reduce exposure to the cat flea which can be quite dangerous to a young cat. A genuine infestation can cause anaemia in a kitten and on occasions can be fatal.
As a result, this appears to be a good strategy by a concerned mother, although it has to be said that this proposed reason is speculative because there is no evidence to support it.
Another possible reason why a mother indulges in kitten nest-moving is to reposition the nest to a place where it is nearer a source of food thereby making it easier to feed her young because there will be less expenditure of energy in finding food. It is hard work from mother to feed her young and she has to eat well herself.
Another reason why a mother may move her kittens using the classic “scruffing reflex” is to try to ensure that they are kept warm and dry. Young kittens are very vulnerable to cold. Is important that they are kept at a good temperature and a draughty, wet den site may result in the kittens becoming ill. Also damp wet conditions favour the transmission of viruses that cause upper respiratory infections.
Many feral kittens die of cat flu. Occasionally, I have seen photographs of rescued feral cats or semi-feral cats who had become blind because an upper respiratory infection has developed into a bacterial infection which has attacked the cat’s eyes to an extent where the eyes have become so severely damaged that they cannot be saved by a veterinary surgeon.
As an afterthought, I am informed, that some veterinarians use the scruff reflex to calm cats when they are at the clinic. Veterinary nurses sometimes apply a line of clothes pegs to the area of skin between the top of the head and the shoulders. This allows the nurse to examine the cat without causing the cat too much stress and, I presume, that at the same time, it also protects the nurse from possible scratches should the cat be agitated.
Photo: by Margo Akermark (modified by me)
Ref: (1) John Bradshaw