For the most part, our cats are neutered to prevented unwanted kittens and we think of them as sex-less. That’s until Tiddles starts humping a sweatshirt, Fluffy gets amorous with a leather handbag or Ginger launches an attack on you during an amorous moment resulting in “cattus interruptus”.

There’s more to a cat’s sex drive than just the testes or ovaries. A degree of it may be psychological, especially in late-neutered animals (in cats neutered before or at puberty, what you’ve never had doesn’t seem to be missed). Sometimes an odour can trigger mating behaviour in a happily neutered cat that has never previously shown an interest in the opposite sex. Sometimes, the cat, neutered or otherwise, develops a carnal interest in an inappropriate object or even another animal.

Peter Neville, in his excellent book “Pet Sex” documented several cases of sex-pest cats. In my own two decades of dealing with cats – both as an owner and at a cat shelter – I’ve come across quite a few “purr-verts” myself. In most cases, there is a logical explanation for what an owner sees as abnormal behaviour. We just have to see the world through a cat’s eyes, or more often through a cat’s nose!

NORMAL BEHAVIOUR IN AN ABNORMAL SETTING

Does your female cat lift her rump and cock her tail to one side when her back or neck is stroked. If you also scratch or pinch her scruff does she go into raptures? It isn’t peculiar to pet cats; naturalist Mike Tomkies noticed this behaviour in a Scottish Wildcat called Liane that shared his home. This “bum up” position is the lordosis position she adopts when soliciting a tom to mount her. Neutered females and even neutered males will do this. During heavy stroking, they might flatten themselves to the ground, chirrup and even look round at the owner while sticking their bottoms in the air.

While the behaviour is sexual in origin, in neutered pets it has been turned into a gesture of affection. All your stroking is a bit like feline foreplay, but don’t worry - your cat doesn’t actually expect nookie, it’s just showing you how good it feels! If the “bum up” behaviour is literally a bit too “in your face”, a gentle puff of air will usually persuade your cat to move position – much as they like to present their bottoms, they don’t like the wind up their tail.

Unneutered male cats may also display sexual behaviour towards the owner or inanimate objects. My mother recalls the cats of her childhood when neutering was uncommon mating with straw bags and even trying to mount her head while she sat on the stairs. According to her, the family cat Sandy would have been more appropriately named Randy.

These days neutering prevents or reduces such behaviour. Just as an uncastrated dog might hump an owner’s leg, a male cat approaching sexual maturity might mount the owner’s arm, grasping flesh in their jaws and treading with the hind legs (or thrusting with the groin). Caterwauling and an other-worldly expressing may accompany these acts. Even if the cat is under 6 months old (the traditional neutering time in many countries), if he’s showing this behaviour it’s probably time to get him snipped. Those owners that are opposed to neutering or insist on vasectomy rather than castration may end up with a hairdo-humping cat like my mother’s Sandy.

Scrapper was my late-neutered ex-feral moggy. When I took in a young female stray, just on the verge of puberty, Scrapper’s dormant urges resurfaced. However the target of his affection was not young (and now spayed) Aphrodite, it was one of my sweaters. I should feel complimented that he’d fixated on me as a partner and vigourously humped a jumper that smelled strongly of me. If I spoke to him while he was servicing his acrylic partner, he redoubled his efforts. Apart from the odd occasions when I wore it to renew my scent, the jumper was donated to Scrapper and he continued to love it for many months until kidney disease claimed him.

Unneutered female cats have sometimes allowed themselves to be mated, or at least mounted, by small dogs or large rabbits. My friend’s tortie female, who was on contraceptive implants as anaesthesia was too risky, backed herself under a leather handbag in the hope it would mate with her! At the height of her sex-seeking, the sight, sound and smell of lusty Spud even induced a couple of castrated males in the household to mount her.

Unneutered males and even some neutered males will mount small dogs and other pets such as rabbits and guinea pigs… and in one case attempted to mount a roosting chicken. Siamese males are notorious for sexy behaviour even long after castration. Where an animal isn’t available, an inanimate object will suffice as in the case of Scrapper mentioned earlier.

NOT TONIGHT, I’M ON MY MENSTRUAL CYCLE

Most owners are aware their cats respond to pheromones. Most know that unneutered tomcats spray urine as territorial markers, but fewer will have observed female cats approaching oestrus reacting ecstatically to pungent tomcat spray. The pheromones of a female in heat can attract toms from miles around. With this in mind, it’s not surprising our cats react to similar scent cues in their humans.

Many years ago, I lived next door to a couple that had a lovely, affectionate neutered male called Tiger. Tiger loved riding round on my shoulders. He also loved riding round on his female owner’s shoulders, but she was less keen on this because Tiger kept biting her neck. This behaviour was periodic in more ways than one - Tiger was responding to his owner’s menstrual cycle. Unlike her, I was on the contraceptive pill and didn’t give the olfactory cues that Tiger responded to.

GETTING IN ON THE ACTION

Us humans like to cover up our natural body odours with deodourants and colognes. The only time we seem happy to let our natural odours waft free is during sex. This is why so many cats seem intrigued by human sexual activity. Most are content to remain voyeurs, but a few are intrigued enough by the sounds and smells to investigate more closely. This tends to be disconcerting for owners. Even more disconcertingly, some cats may view the bobbing body parts as prey and launch an attack.

If you’re disconcerted by feline attention or intervention during intimate moments, the easiest solution is to shut the cat out of the room for a little while. Having said that, many couples allow their cat(s) to remain on the bed during proceedings. My own cats’ reactions were more along the line of annoyance that the bed was shaking while they were trying to sleep.

Spare a thought for the poor chap whose cat had a condition called pica that drove it to munch unsuitable items. In this case (reported by behaviourist Peter Neville), the cat liked the taste of rubber or latex. Keeping his condoms in a drawer prevented them being consumed or punctured before use, but the cat’s behaviour reached its climax when the misguided moggy bit into a condom after it had been donned.

PURRING PERVERTS

While some of our cats’ sexual behaviour seems bizarre at first glance, it normally makes sense when we view the world from the cat’s point of view.

Scrapper was responding to female cat pheromones and transferred his attention to a more receptive, albeit inanimate, partner.

In Pet Sex, Peter Neville documented the case of a neutered indoor male cat that became amorous with a plastic bag full of conkers. The cat was too much of a scaredy cat to go outdoors and hadn’t shown any sexual behaviour before, but for some reason the plastic bag of conkers turned him on. He began by inhaling the scent from the bag and doing the flehmen (grimace)reaction to taste the scent. Somehow, the odours from the conkers resembled the odour of a receptive female, because he then showed every indication of wanting to mate.

Similarly, when a neutered male persistently “raped” the female dachshund he shared the house with, it turned out the dog had an ovarian cyst and was producing an abnormal amount of attractive pheromones that the castrated cat could not resist. Once the bitch was spayed, the cat lost interest and peace was restored. Another tomcat was sexually fixated on a Continental Giant rabbit that patiently put up with being mounted by the sex-obsessed feline. The solution was to modify the rabbit’s run to keep her ardent feline suitor out.

A similar olfactory cue was behind one neutered tom’s fixation with a radiator knob. Whenever the radiator began to warm up, the cat humped the control knob at one end of it. The only feasible explanation was the type of sealant used gave off fumes when the pipe warmed up and the fumes triggered the behaviour.

GAY CATS?

Homesexual behaviour is seen in many social animals and is well documented in Bruce Bagemihl’s book “Biological Exuberance; Animal Homosexuality and Natural Diversity”. Dolphins do it and bonobos are renowned for it. While frequently dismissed as dominance behaviour, some animals, like humans, are attracted to same sex partners indicating a genetic cause (perhaps affecting the brain structure) for homosexuality. Not being social animals, same-sex activities are rarer in cats.

While working at the cat shelter we took in a pair of male cats that we believed neutered. They had been indoor-only companions for years and did not spray or caterwaul. When a female in another pen went into oestrus, the two males went into a frenzy of mating each other. It turned out that neither was neutered and their sexual behaviour had somehow remained suppressed until they encountered the scent of a receptive female. Unable to reach the female, they turned to only available mate – each other. Neutering eliminated this and they remained companions, albeit now wholly platonic.

Sometimes, an adult cat will mount another cat to assert dominance. This may happen when the owner tries to introduce another cat into the household. Sometimes it’s enough for one cat to assert dominance, but sometimes the behaviour continues to the point where the new cat must be rehomed. Though more common where the dominant cat is male, even female cats will sometimes use mounting and the neck-grasp to put another cat in its place, but this is more often attributed to maternal behaviour – females will sometimes pin down kittens when they get too feisty!