Feline Communication Behaviour

Introduction

Cats use the three sensory channels for communication; sight, sound and scent. Each of these has certain advantages and disadvantages for communication. Communication in the cat has evolved to enable cats to maintain distance from each other both in time and space, primarily through a system of chemical signals.

Affiliative Behaviour

In the typical affiliative behaviour, a cat will approach and then move its tail into a vertical position (tail-up). A quiet trill or chirrup is issued, and after getting to within around 0.5 metres the approaching cat will sit down. Slow eye blinking is also used to indicate that this is a friendly approach. Physical contact only occurs between cats in in about 30% of these approaches. Two cats may approach each other with tail-up, in which case they will often sit down in close proximity, but still without physical contact. When cats do make contact during a greeting, it is often only briefly; one or two rubs or a brief period of grooming. Cats that are younger than 2 years of age are more sociable and also more likely to engage in closer contact after a greeting, possibly even playing.

Visual communication

The function of the visual system of cats is highly biased in favour of predatory behaviour. The cat’s retina has three times the rod density of the human eye, contributing to the light detection threshold in cats being eight times lower than in man. Although their vision is not monochromatic, cats have sixteen times fewer wavelength comparing retinal ganglia than primates and are behaviourally colour blind. The cat’s enhanced visual sensitivity to brightness, patterns and movement block learning associated with differences in colour; under normal conditions cats do not appear to learn associations based on colour discrimination. The optic nerve in the cat has a much lower density of nerve fibres than in man, due to the much smaller amount of information transmitted from the cat’s retina. This is because the ratio of ganglionic cells to photoreceptors is very high in the cat; there is a far higher level of integration of information at the level of the ganglionic layer of the retina. The benefit of this is that movement detection is hard-wired into the sensory system and able to directly drive fast responding reflexive systems; the cat is therefore much more rapidly attentive and responsive to movement that a human. In a sense, cats “see movement” in the way that we see colour. Overall, its vision has evolved to enable it to see in low light levels, break the camouflage of its prey and quickly detect movement. As a result of the wild cat’s camouflaged coat, crepuscular and nocturnal activity and stealthy use of cover, visual identification of affiliates is less important than the use of other sensory systems such as olfaction.

Visual communication involves facial and body postures, as well as the visual aspects of certain behaviour such as spray marking and clawing. In general, visual communication is operates over a limited range, in line of sight and is rapidly modified. This gives the signaller a great deal of control over the signal, which can be changed according to the response it elicits. Visual signalling is less effective at night, in adverse weather conditions and dense undergrowth. The main disadvantage of visual communication is that it must be delivered face to face with a competitor, which increases the risk of conflict and injury.

Visual communication in cats therefore tends to be vivid. Whole body signals are used to make the signaller appear larger and more threatening, or smaller and less threatening. The most powerful signals are those at the extreme, such as the side-on body posture with arched back and tail erect.

The intention of all body posture signalling during a conflict is to maintain distance between individuals, either by intimidating an opponent into a retreat, or by indicating such a low level of threat that an opponent has no need for an approach. The roll is not a position of complete vulnerability in cats, and in this position the cat is able to make very good use of its teeth and all sets of claws. After a conflict, both parties go their separate ways and so there is no need for post-conflict resolution.

Facial posture is extremely important in conveying momentary changes in the emotional state of the cat. Changes in ear position, pupil dilation and the display of teeth are not paralleled by body posture changes, since these are slower to accomplish, especially one the animal has adopted a fully erect or very low body position.

Cats are not asocial, they will live in large colonies where resources are plentiful and they do develop affiliative relationships with each other. So, distance reducing behaviours are an essential part of communication that allows cats to approach one another.

This is particularly important when we consider that cats have evolved a system of establishing group identity using odour, through allorubbing and allogrooming. It would not be possible to establish a group odour if cats did not have some communicative mechanism for reducing distance.

Vocal communication

Vocal communication includes a wide range of sounds from quiet purrs and trills to loud distress vocalisations. Vocal signals can vary from short to long range, but are always omnidirectional and carry a risk of being detected by cats other than the intended recipient. Vocal communication can be used at a distance in any weather or lighting conditions.

In general sounds that are produced with the mouth closed, such as purrs, trills and chirrups, are distance-reducing signals. The same is true of vocalisations that are produced with the mouth initially open but closing whilst the sound is produced, such as the miaow. Strained intensity vocalisation that are made with the mouth open throughout the sound are generally distance increasing signals or signs of distress, such as growls, hisses, spits, snarls and shrieks.

Olfactory communication

Olfactory communication involves the deposition of scent marks in the environment to convey a signal indirectly to another individual. Scent signals are persistent, localised and indirect. They cannot be removed by the signaller once they have been deposited and thus they can convey information about the presence of the signaller that may be to its detriment. For example, rodents have been shown to exhibit unconditioned fear and avoidance behaviour in response to feline odours. In a further twist, Toxoplasma gondii infection in rodents has been shown to have a highly specific effect on this aversive response, producing not just a loss of fear of feline urine pheromone odours, but also an attraction to them. This enables parasite to continue its life cycle by infection of its feline definitive host. The behavioural changes seen are completely specific to feline odours, with other fear and conditioning responses remaining unaffected. Scent signals can also carry a considerable distance, as is the case in urinary scent marks by females during the reproductive season.

Scent signals carry both information and meaning. The information relates to the signaller; its identity, health and reproductive state. The personal identification element of the signal has common features between claw marks, spray marks and facial/flank marks, so that the recipient of any of these signals will be aware of which individual is responsible. Previous experience with that individual adds value to this information. Meaning is conveyed in the position and type of signal used.

• Facial and flank marks are signals largely used in a cat’s core territory, where it only expects to encounter other familiar cats.
• Spray marks are used to maintain temporal separation by indicating information about ownership of space as well as when a particular cat visits that location.
• Claw marking is used to stretch back muscles after resting, as well as to maintain the condition of claws, so owners are often confused about its meaning as a form of communication. When scent is released from pedal glands during clawing, this creates a signal that indicates territorial residency.

Claw, urine and facial/flank marks are generally deposited on vertical surfaces, often on objects that are close to an entry point to a particular space, so that other cats will notice them.

Pheromones

The meaning of the chemical signal is conveyed using pheromones that form part of the spray, claw or facial/flank mark. Unlike the releaser pheromones that are found in insects, which have a direct and immediate effect on behaviour, mammalian chemical signals have a more subtle effect on mood, emotion and behavioural priorities. For example, in the presence of female sex pheromone a male cat will continue with its current behaviour but its priorities will shift toward seeking out a mate.

In cats, pheromone signals are composed of combinations of fatty acids that are deposited together on a scent marked site. Cat urine also contains the strong smelling compound 3-methyl-3-methylbutan-1-ol (MMB), which a chemical signalling function. This is produced by the action of the enzyme cauxin, which hydrolyses the chemical felinine that is synthesised in the liver and excreted in urine.

The recipient of the signal will sniff the location, and may perform a Flehmen behaviour in order to draw a larger quantity of pheromone through ducts opening form the roof of the mouth and floor of the nasal cavity into a specialised chemosensory organ called the vomeronasal organ (VNO). The VNO consists of a pair of 1-2cm long tubular organs in the hard palate. Once in the VNO pheromone chemicals bind to a pheromone binding protein before being presented to cell-surface receptors. Signals from the VNO are directed toward primitive brain structures such as the amygdala, that are involved in subconscious changes in mood, emotion and motivation.

Spray Marking

The rate of spray marking by male and female cats is increased during the period when females are in oestrus. As a result, the rate of spray marking in males and females decreases after neutering, as does the pungency of the male spray mark.

Both spray marking and claw marking also include an element of visual display. During spray marking, the cat will sniff the site to be marked, using a Flehmen behaviour to collect more of the pheromone signal. Then it will back up to the site to be sprayed, with its tail raised. During the act of spraying the cat’s tail twitches and moves, the cat has a glazed look in its eye and it will often make treading movements with its hind feet. This pattern is distinct from urination which is usually on horizontal surfaces (unless the cat has urinary tract disease) and is not accompanied by tail movements or treading.

xxx

When cats rub against each other and groom each other they transfer scent to create a common group odour. In wild or feral cat groups, individuals may already share strong odour similarities since in most cases groups are composed of related females. Allorubbing and allogrooming of this kind are essential to social bonding but do not contribute to self-maintenance; cats can groom themselves successfully without assistance form others.

Key points

• The visual system of cats is predominantly adapted to suit predatory behaviour.
• Movement detection is greatly enhanced in the cat’s visual system, to the detriment of colour vision and visual acuity.
• Recognition of the identity of conspecifics is therefore more likely to be based on other sensory information, such as odour.
• Distance increasing visual and vocal signals between cats tend to be vivid, so that they can be delivered at sufficient distance to avoid fighting.