Catwatching

by Desmond Morris

  If the attempt to hunt a bird on an open lawn is so doomed to failure, why does the cat keep trying? The answer is that every cat has a powerful urge to go hunting at regular intervals, but this urge has been severely hampered by advances in human pest control. In town and cities and suburbs, the rodent population that used to infest houses and other dwellings has been decimated by modern techniques. Garden birds may be pests, but their appeal to human eyes has protected them from a similar slaughter. As a result, the rodent-hunting cat finds itself today in an unnaturally mouse-free, bird-rich environment. It cannot utilize its natural hunting skills under such conditions. It is this state of affairs that drives the cat on to crouch hopelessly but compulsively on open lawns, staring longingly at elusive birds. So when it waves its tail at its prey on these occasions, it is not the cat which is a stupid hunter, but we who have unwittingly forced a clever hunter to attempt an almost impossible task.

  Why does a cat chatter its teeth when it sees a bird through the window?

  Not every owner has observed this curious action, but it is so strange that it is a case of 'once seen never forgotten'. The cat, sitting on a window-sill, spots a small bird conspicuously hopping about outside and stares at it intently. As it does so it begins juddering its teeth in a jaw movement which has variously been described as a 'tooth-rattling stutter', a 'tetanic reaction' and 'the frustrated chatter of the cat's jaws in the mechanical staccato fashion'. What does it mean?

  This is what is known as a 'vacuum activity'. The cat is performing its highly specialized killing-bite, as if it already had the unfortunate bird clamped between its jaws. Careful observation of the way in which cats kill their prey has revealed that there is a peculiar jaw movement employed to bring about an almost instantaneous death.

  This is important to a feline predator because even the most timid of prey may lash out when actually seized, and it is vital for the cat to reduce as much as possible any risk of injury to itself from the sharp beak of a bird or the powerful teeth of a rodent. So there is no time to lose. After the initial pounce, in which the prey is pinioned by the strong claws of the killer's front feet, the cat quickly crunches down with its long canine teeth, aiming at the nape of the neck. With a rapid juddering movement of the jaws it inserts these canines into the neck, slipping them down between vertebrae to sever the spinal cord. This killing-bite immediately incapacitates the prey and it is an enactment of this special movement that the frustrated, window-gazing cat is performing, unable to control itself at the tantalizing view of the juicy little bird outside.

  Incidentally, this killing-bite is guided by the indentation of the body outline of the prey – the indentation which occurs where the body joins the head in both small birds and small rodents. Some prey have developed a defensive tactic in which they hunch up their bodies to conceal this indentation and in this way make the cat miss its aim. If the trick works, the cat may bite its victim in part of the body which does not cause death, and on rare occasions the wounded prey may then be able to scrabble to safety if the cat relaxes for a moment, imagining that it has already dealt its lethal blow.

  Why does a cat sway its head from side to side when staring at its prey?

  When a cat is preparing to pounce on its prey it sometimes sways its head rhythmically from side to side. This is a device employed by many predators blessed with binocular vision. The head-sway is a method of checking the precise distance at which the prey is located. If you sway your own head from side to side you will see how, the closer an object is, the more it is displaced by the lateral movements. The cat does this to refine its judgment, because when the rapid pounce forward is made it must be inch-accurate or it will fail.

  Why does a cat sometimes play with its prey before killing it?

  Horrified cat-owners have often experienced the shock of finding their pet cats apparently torturing a mouse or small bird. The hunter, instead of delivering the killing-bite of which it is perfectly capable, indulges in a cruel game of either hit-and-chase or trap-and-release, as a result of which the petrified victim may actually die of shock before the final coup de grace can be delivered.

  Why does the cat do it, when it is such an efficient killing machine?

  To start with, this is not the behaviour of a wild cat. It is the act of a well-fed pet which has been starved of hunting activity as a consequence of the 'hygienic' environment in which it now lives – neat suburbs or well-kept villages where the rodent infestation has long since been dealt with by poison and human pest control agencies. For such a cat, the occasional catching of a little field mouse, or a small bird, is a great event. It cannot bear to end the chase, prolonging it as much as possible until the prey dies. The hunting drive is independent of the hunger drive as any cat-owner knows whose cat has chased off after a bird on the lawn immediately after filling its belly with canned cat food. Just as hunger increases without food, so the urge to hunt increases without access to prey. The pet cat over-reacts, and the prey suffers a slow death as a result.

  On this basis, one would not expect feral cats which are living rough or farm cats employed as 'professional pest-controllers' to indulge in play with their half-dead prey. In most cases it is indeed absent, but some researchers have found that female farm cats do occasionally indulge in it. There is a special explanation in their case. As females, they will have to bring live prey back to the nest to demonstrate killing to their kittens at a certain stage in the litter's development. This maternal teaching process will account for an eagerness on the part of females to play with prey even though they are not starved of the hunting process.

  There is one other explanation for this seemingly cruel behaviour.

  When cats attack rats they are quite nervous of their prey's ability to defend themselves. A large rat can give a nasty bite to a cat and has to be subdued before any attempt is made to perform the killing-bite.

  This is done by the cat swinging a lightning blow with its claws extended. In quick succession it may beat a rat this way and that until it is dazed and dizzy. Only then does the cat risk going in close with its face for the killing-bite. Sometimes a hunting cat will treat a small mouse as if it were a threatening rat, and start beating it with its paws instead of biting it. In the case of a mouse this quickly leads to a disproportionately savage pounding, with the diminutive rodent being flung to and fro. Feline behaviour of this type may appear like playing with the prey, but it is distinct from the trap-and-release play and should not be confused with it. In trap-and-release play the cat is inhibiting its bite each time. It is genuinely holding back to prolong the hunt. In hit-and-chase attacks on mice the cat is simply overreacting to the possible danger from the prey's teeth. It may look like cruel play, but in reality it is the behaviour of a cat that is not too sure of itself. Even after the prey is nearly or completely dead, such a cat may continue to bat the victim's body around, watching it intently to see if there is any sign of retaliation. Only after a long bout of this treatment will the cat decide that it is safe to deliver the killing-bite and eat the prey.

  An experienced, full-time hunter would not react in this way, but a pampered pet cat, being a little rusty on the techniques of a quick kill, may well prefer this safer option.

  How does a cat prepare its food?

  Immediately after the kill, a cat goes through the strange little routine of 'taking a walk'. Unless it is starving, it paces up and down for a while, as if feeling the need to release the tension of the huntand-kill sequence. Only then does it settle down to eating the prey.

  This pause may be important for the cat's digestion, giving its system a chance to calm down after the adrenalin-excitement of the moments that have just passed. During this pause a prey that has been feigning death may try to escape and, on very rare occasions, succeeds in doing so before the cat can return to the hunting mood again.

  When the cat finally approaches its prey to eat it, there is the problem of how to prepare it for easy swallowing. Small rodents cause no diffi
culties. They are simply eaten head first and the skins, if swallowed, are regurgitated later. Some cats separate out the gallbladder and intestines and avoid eating them, but others are too hungry to care and gobble down the entire animal without any fuss.

  Birds are another matter because of their feathers, but even here the smaller species are eaten in their entirety, with the exception of tail and wing feathers. Birds the size of thrushes and blackbirds are plucked a little before eating, but then the cat impatiently starts its meal.

  After a while it breaks off to remove a few more feathers, before eating further. It repeats this a number of times as the feeding proceeds.

  Bigger birds, however, demand more systematic plucking, and if a cat is successful at killing a pigeon or something larger, it must strip away the feathers before it begins to eat.

  To pluck a pigeon, a cat must first hold down the body of the bird with its front feet, seize a clump of feathers between its teeth, pull its jaw-clamped head upwards with some force, and then finally open its mouth and shake its head vigorously from side to side to remove any clinging plumage. As it shakes its head it spits hard and makes special licking-out movements with its tongue, trying to clear its mouth of stubbornly attached feathers. It may pause from time to time to lick its flank fur. This last action puts grooming into reverse.

  Normally the tongue cleans the fur, but here the fur cleans the tongue.

  Any last remnants are removed and then the next plucking action can take place.

  The urge to pluck feathers from a large bird appears to be inborn. I once presented a dead pigeon to a wild cat living in a zoo cage where it had always been given chunks of meat as its regular diet. The cat became so excited at seeing a fully feathered bird that it started an ecstatic plucking session that went on and on until the whole body of the bird was completely naked. Instead of settling down to eat it, the cat then turned its attention to the grass on which it was sitting and began plucking that. Time and again it tugged out tufts of grass from the turf and shook them away with the characteristic bird-plucking movements until, eventually, having exhausted its long-frustrated urge to prepare its food, the cat finally bit into the flesh of the pigeon and began its meal. Clearly, plucking has its own motivation and can be frustrated by captivity, just like other, more obvious drives.

  The strangest feature of feather-plucking is that Old World Cats perform it differently from New World Cats. All species from the first area perform a zigzag tugging movement leading to the full shake of the head, while those from the Americas tug the feathers out in a long vertical movement, straight up, and only then perform the sideways shake. It appears that, despite superficial similarities between the small cats from the two sides of the Atlantic, they are in reality two quite distinct groups.

  How efficient is the cat as a pest-killer?

  Before the cat became elevated to the level of a companion and pet for friendly humans, the contract between man and cat was based on the animal's ability to destroy pests. From the time mankind first started to keep grain in storage, the cat had a role to play and carried out its side of the bargain with great success. Not so long ago it was thought that the best way to get farm cats to kill rats and other rodent pests was to keep the feline hunters as hungry as possible.

  This seemed obvious enough, but it was wrong. Hungry farm cats spread out over a huge hunting territory in search of food and killed fewer of the pests inside the farm. Cats that were fed by the farmer stayed nearer home and their tally of farm pests was much higher. The fact that they had been fed already and were not particularly hungry made no difference to the number of prey they killed each day, because the urge to hunt is independent of the urge to eat. Cats hunt for the sake of hunting. Once farmers realized this they were able to keep their cats close by the farm and reduce the damage done to their stores by rodent pests. A small group of farm cats, well looked after, could prevent any increase in the rodent population, providing a major infestation had not been allowed to develop before their arrival.

  According to one authority, the champion mouser on record was a male tabby living in a Lancashire factory where, over a very long lifespan of twenty-three years, he killed more than 22,000 mice. This is nearly three a day, which seems a reasonable daily diet for a domestic cat, allowing for some supplements from human friends, but it is far exceeded by the world's champion ratter. That honour goes to a female tabby which earned her keep at the late lamented White City Stadium.

  Over a period of only six years she caught no fewer than 12,480 rats, which works out at a daily average of five to six. This is a formidable achievement and it is easy to see why the ancient Egyptians went to the trouble of domesticating cats and why the act of killing one was punishable by death.

  Why do cats present freshly caught prey to their human owners?

  They do this because they consider their owners such hopeless hunters.

  Although usually they look upon humans as pseudo-parents, on these occasions they view them as their family – in other words, their kittens. If kittens do not know how to catch and eat mice and small birds, then the cat must demonstrate to them. This is why the cats that most commonly bring home prey and offer such gifts to their owners are neutered females. They are unable to perform this action for their own litters, so they redirect it towards human companions.

  The humans honoured in this way frequently recoil in horror or anger, especially if the small rodent or bird is still half-alive and struggling. The cat is totally nonplussed by this extraordinary response. If it is scolded for its generous act, it once again finds its human friends incomprehensible. The correct reaction would be to praise the cat for its maternal generosity, take the prey from it with many compliments and strokings and then quietly dispose of it.

  Under natural conditions a cat which has a litter of kittens introduces them to prey animals little by little. When they are about seven weeks old, instead of killing and eating her prey where she catches it, she kills it and then brings it back to where the kittens are kept. There she proceeds to eat it while they watch. The next phase involves bringing the dead prey back and playing with it before consuming it, so that the kittens can see her beating it with her claws and grabbing it.

  The third phase involves leaving the prey to be eaten by the kittens themselves. But she is still not prepared to risk bringing a live or even a half-dead prey to the kittens, because it could easily bite them or attack them if they are unwary. Only when they are a little older will she do this, and then she herself will make the kill in front of the kittens. They watch and learn. Eventually they will accompany her on the hunt and try killing for themselves.

  Why do cats eat grass?

  Most cat-owners have observed the way in which, once in a while, their pet goes up to a long grass stem in the garden and starts to chew and bite at it. Cats living in apartments where there are no gardens in which to roam have been known to cause considerable damage to house plants in desperate attempts to find a substitute for grasses. In rare cases such cats have even harmed themselves by biting into plants that are poisonous.

  Many cat experts have puzzled over this behaviour and some have admitted frankly that they have no answer. Others have offered a variety of explanations. For many years the favourite reply was that the cats use grass as a laxative to help them pass troublesome hairballs lodged in their intestines. A related suggestion claimed that they were eating grass to make themselves vomit up the hairballs.

  This was based on the observation that cats do sometimes vomit after eating grass, but it overlooked the possibility that whatever made the cats feel sick also made them want to eat grass, rather than that the grass-eating actually caused the vomiting.

  A less popular explanation was that the grass aided the cats in the case of throat inflammation, or irritation of the stomach. Some authorities simply dismissed the activity as a way of adding roughage to the diet.

  None of these explanations makes much sense. The amount of grass actually e
aten is very small. Watching the cats chewing at long grasses, one gets the impression that they are merely taking in a little juice from the leaves and stems, rather than adding any appreciable solid bulk to their diet.

  The most recent opinion and the most likely explanation is that cats chew grass to obtain minute quantities of a chemical substance that they cannot obtain from a meat diet and which is essential to their health.

  The substance in question is a vitamin called folic acid, and it is vital to cats because it plays an important role in the production of haemoglobin. If a cat is deficient in folic acid its growth will suffer and it may become seriously anaemic. Cat-owners whose animals have no access to grasses of any kind sometimes solve the problem by planting grass seeds in a tray and growing a patch of long grass in their apartments for their pets to chew on.

  Incidentally, it is worth pointing out that although cats may need this plant supplement to their meat diet, they are first and foremost carnivores and must be treated as such. Recent attempts by well-meaning vegetarians to convert their cats to a meat-free diet are both misguided and cruel. Cats rapidly become seriously ill on a vegetarian diet and cannot survive it for long. The recent publication of vegetarian diets recommended as suitable for cats is a clear case of animal abuse and should be dealt with as such.