In order to understand “humping” or “mounting” one ideally needs to study the dog in situ as the reasons may vary and the only way to get a good idea of why a dog is behaving in this way is to observe it. Certainly the latest studies state that it is “not” always dominance that causes the “hump” but that it is much more to do with “arousal”. Often a mounting behaviour might be mistaken as humping but the true hump includes the pelvic thrusting action. Female dogs can exhibit this behaviour also so it is not just seen in males.
According to Spiegel he says: “Humping can be related to heightened excitement levels, so training can take the excitement level down”.
Landsberg states that mounting is a common dominance gesture with dogs, although it doesn’t mean the dog that is doing the humping is dominant. In fact, dogs that are unsure of their place in the pack are more likely to hump to see how many dogs will accept the behaviour, a move that can lead to fights with other dogs.
In Fogle’s book “The Dog’s Mind” he says: “Something like the scent of a bitch in oestrus (or often the sight of a favourite stuffed toy or cushion) stimulates the hypothalamus to secrete releasing factors which in turn cause the pituitary gland to increase LH production (luteinising hormone) and this in turn stimulates the testicles to produce more testosterone” and this of course all comes together when a dog reaches puberty and dramatic behavioural changes can occur.
1 Dogs can hump because a female is in heat and this is the “real sexual act” if mating takes place. The female will be a willing partner in this if she accepts the male.
2. Humping as displacement behaviour – when a dog is unsure and does not really know what to do behaviours that are “out of place” can occur and so humping can be one of those. Dogs can be so excited they don’t know what to do with themselves and humping may occur as a kind of release. One dog may then mount another and start to hump but he/she may even be sideways on or at the head of the other dog, it may be a pillow the dog humps or a soft toy etc. Because this then makes the dog feel good, dogs can end up performing the act again and again which can lead to “serial humping”!
3. An adult humps an adolescent dog – the adolescent’s hormones are active and both male and female hormones are present in higher than usual concentrations. The mounting/humping behaviour is then often out of confusion and a level of excitement because of the smell the adolescent is giving off. Many adolescents also go through a humping phase and mount anything – such as pillows, human legs and such like. Adolescent males have testosterone surging through their bodies and this reaches its peak around 10 months – this can be a time of confusion and new feelings for a dog.
4. Some castrated males may have more female hormone in their bodies and end up being mounted by other males. Fogle says: “It seems that testosterone, the male hormone, is actually converted to a hormone that is similar to the female hormone oestrogen before it can influence the brain. Studies have show that the administration of the female hormone oestrogen can stimulate male sex behaviour such as mounting or even perhaps aggressive behaviour”.
5. Humping can be part of play and it can be a way of putting scent on another dog. Where dogs are in adolescence this can become highly addictive “risk taking” behaviour and it can get them in trouble! It activity can make them feel really good (no surprise there) and this can mean they repeat it so much that it really does become an addiction. Redirection into other activities is really important so that they don’t get highly aroused. High arousal can tip into aggression and these dogs can turn into bullies. Hump the wrong dog along with generally being rude can all too easily lead to a dog fight!
For more information on canine sex hormones and neutering, see this article