In years gone by horses were left to roam the plains, free to do what they liked. Normal feral (untamed) behaviour is quite complicated, with different social hierarchical groups and complex herd communication. In the wild horses are responsible for all aspects of their survival, domesticated horses on the other hand rely on us for this, for example providing food, body care/grooming and thermoregulation (maintaining body temperature).
The majority of horses adapt very well to domestication, but they are exptected to live in small stables and graze in small, enclosed areas, and this environmental change, compared to their feral counterparts, gives rise to a range of abnormal behaviours that can be distressing for both horse and owner. It is important that we ensure our horses are kept in the most comfortable conditions possible to ensure their health and sanity!
Your questions answered
What is aggression?
Aggression is primarily a form of communication used to establish precedence and consists of threats or harmful actions directed towards an individual. Horses in the wild show very little overt physical aggression as they normal live in stable social groups. When they do occur, aggressive encounters are normally short-lived and end with one individual retreating away from the situation. Broadly speaking aggression occurs when a horse perceives some form of threat to itself or when frustrated. Horses are not maliciously aggressive, although some medical problems can result in severe aggressive behaviour. It is important to differentiate aggression from potentially similar looking behaviours which can cause injury such as play fighting, nipping and overzealous grooming behaviour.
Aggression can be subdivided into type based on target, eg owner or horse directed, and body postures (offensive and defensive); alternatively other factors such as the focus of competition, eg food related, the involvement of disease, eg pain related, or hormonal status of the animal involved, eg maternal aggression. These terms are merely contextual cues which help clarify the circumstances of the behaviour. It is important to appreciate that in most cases a horse is behaving aggressively because it perceives some form of threat to itself (this may be real or imaginary) and has no opportunity to escape from the situation.
Are aggressive horses normal?
How do horses communicate their aggressive intent?
By watching the body postures, it is possible to get an indication of what a horse may do. When a horse is reacting to intrusion, the first sign may be simply a laying back of the ears or wrinkling of the nose. If the horse is likely to lunge forward in an offensive way, the tail often becomes raised and the head is thrust forwards with a possible attempt made at biting. Before an overt charge the horse is likely to show its intention through powerful lashing of its tail and a stamping of its feet first; this type of aggression is more commonly seen when the horse is trying to protect something nearby, eg a mare with her foal. More commonly, horses turn their rump towards a threat in order to deter further approach (rather than drive away as occurs with a frontal assault), the tail is normally tucked in and a foot will usually be raised first as a threat and kicking only follows if this signal is ignored. The horse may kick with one or both hind feet.
A couple of important behaviours which should not be mistaken for aggressive behaviour are jaw snapping and turning away. In jaw snapping the lips are pulled back to expose champing teeth, the head is usually lowered and the tail tucked. This is not an aggressive behaviour but rather a form of cautious approach indicating unease in the situation and sometimes may be a sign that the horse is looking for guidance about what it should do. Turning away with the ears loose or half back is a behaviour used by a horse to indicate that it is giving way to another. Obviously in both of these situations it is important that these gestures are recognised for what they are and the horse not punished as this may provoke aggression by the horse in response to what it might see as a mindless attack from its handler when it was trying to make the peace.
How should I respond to aggressive behaviours?
The distance between the horse and the intruder can be important in determining the response. This is often called the "flight" zone. If space allows it is normal for one individual to retreat in the presence of threats when its flight zone is crossed. Exactly who it is that retreats, depends on the perceived outcome of the encounter. So if a horse thinks that it is very likely to lose the encounter, or the cost of defence is likely to be very high, or the resource is not very valuable to it, it is likely to retreat in the face of an aggressive threat. However, if any of the opposite conditions apply then it may stand its ground. A horse will also have to stand its ground if it is unable to retreat and this is one of the reasons why aggression is quite common in the stable - it has nowhere to go. Also when a horse is in its stable, it may try to protect the resources it has and value things like its food or personal space very highly and so become protective on them. If someone enters the bock then when it is feeding, the horse may respond aggressively as it sees this intrusion as a threat, even if there is no intention to remove anything.
Horses are also naturally afraid of new or unfamiliar things and circumstances, and may act aggressively towards things they are forced to endure, in an attempt to remove them. It must be remembered that the horse does not know that these things are harmless and that it is still being driven by its evolutionary instincts of self-preservation. Horses are also sensitive to the quality of movement around them, paying more attention to jerky movements than calm, gentle flowing ones. For these reasons horses may be aggressive towards nervous people who enter the stable. It is not surprising that the horse tries to remove the intruder in the only way it knows how, ie through aggressive threats. This does not mean that the horse is nasty, its just a consequence of the circumstances. Unfortunately, this is a self-fulfilling prophecy as this makes the person even more nervous in the future and more likely to be attacked. It is therefore important that nervous individuals are kept away from horses in confined spaces. The best way to calm a nervous horse is to remain relaxed, but to remain vigilant in case the fear heightens and aggression intensifies.
If approached rapidly or carelessly, a horse may go through the stages of aggressive threats very quickly and attack the victim before he/she can react. Horses that are mildly fearful may calm down if the person shows no fear and waits until it settles, without making any gestures that could be seen to be threatening, such as sudden movements. Because most aggression relates to a perceived threat, punishment is generally not appropriate as this confirms to the horse that there was something to be feared and is likely to make matters worse in the long-term and may, in the short-term, result in a serious escalation of the behaviour.
Aggression is the most serious and dangerous behaviour problem that horse owners are likely to encounter. For this reason it is essential to determine accurately the prognosis (the chances of safe and effective correction) through developing an appropriate treatment plan; these problems are usually best handled with a vet or applied animal behaviourist.
Treatment must first be directed at preventing possible injury. This means that aggressive horses should be kept away from nervous or inexperienced individuals, and professional assistance sought as a matter of urgency. The horse should not just be abandoned until it "learns some manners", but will need careful and compassionate re-education.
What are the signs of pain-induced aggression and how can it be treated?
My horse is aggressive at feeding time, what can I do about it?
This is not uncommon and frequently takes one of two forms - protective aggression (discussed above) and barging or aggression due to over exuberance which has accidentally been rewarded. With protective aggression the horse can be taught to accept removal of the food bucket by going through sham exercises. You enter the stable with an empty food bucket and put it in its normal position, the horse is then allowed to inspect the bucket and when it realises that there is nothing there will often allow you to remove it. This is then done and the bucket replaced with a small amount of feed. The main daily feed is then divided up into small amounts and the exercise repeated so the horse learns that removal of the bucket means not that it is losing anything, but that it is a signal for it to return with more in it.
Aggression can also be learned because the horse that is excited by the arrival of the feed, inadvertently nips or barges the handler, who soon gives the horse its feed as this is what they were here to do. In these cases the horse must not be rewarded in this way and the handler must leave the stable with the bucket. They may then return and try again, however, the handler must be prepared for an escalation if the horse gets frustrated. The easiest way to resolve this is to train the horse away from feeding time to respond to a command to go to the back of the stable and slowly introduce this whenever they enter the stable. It helps if the normal feeding time is changed so the horse cannot predict when food is coming. In some cases it is necessary to enter with an empty feed bucket in order to desensitise the horse to this cue. It may also be necessary to tie the horse up prior to feeding while it learns the command.
If your horse is fed from a manger, it is not uncommon for a horse to become aggressive once the food is placed into it. From a horse's perspective, this is the time that the horse takes ownership and so protective responses are triggered. This can be treated using exercises similar to those discussed above, to teach the horse to yield at this point.