Stereotypic behaviours are repetitive behaviours performed by animals with no obviously discernible function.
One of the most commonly recognized stereotypic behaviours is the pacing of polar bears in zoo exhibits. Stereotypic behaviours are also recognized in horses, of which cribbing, weaving and stall walking or pacing are the three most common.
Polar bears and horses share something in common. Whenever their biological needs are not being met in their environment, physiological stress ensues and BOTH will develop behavioural means of coping to physically and mentally support themselves.
Many consider stereotypic behaviours a nuisance, not only because they are annoying and irritating, but because they result in damage to housing and reduce the monetary value of the horse as over time these behaviours affect a horse’s usefulness, dependability and health.
Stereotypic behaviours are often labelled as bad habits and stable vices. Unfortunately this connotation implies the horse to be at fault — needing “fixing” or correction. However, this implication is in error for the common denominator underlying such “ill” behaviours does not lie with the horse itself, rather it lies with the stable life and environment the horse lives in. Stereotypies rarely, if ever, occur in horses living in a relatively rich physical and social environment that is appropriate for their innate being as a horse.
Cribbing occurs when a horse bites down on an object and flexes its neck. The horse then pulls back with its teeth while forcefully swallowing or gulping. This behaviour appears to be related, at least initially, to frustration regarding food availability.
Stall walking or pacing is commonly found in horses that are stabled in box stalls and/or horses confined to a small paddock. Weaving is not unlike pacing except the horse stands in one place rocking back and forth in a repetitive fashion. Both of these behaviours are triggered by the frustration and emotional distress associated with social isolation.
As the horse “drops” or settles into the lull of the repetitive behaviour, the look in its eye changes and it mentally and emotionally dissociates from its surroundings. Over time the movement itself is rewarded by the release of opiates or endorphins that cause the animal to feel better. Once the chemical and physical pathways for endorphin release rewire the horse’s brain, the behaviour becomes nearly impossible to extinguish as the behaviour itself becomes self-rewarding. Physical devices, surgery, aversive conditioning (yes this includes yelling), restraint and pharmacological treatments generally fail to totally eliminate stereotypic behaviours.
Therefore the goal of caretakers is not to stop the horse from the behaviour, rather to focus upon creating a suitable environment where the horse no longer needs to or is motivated to perform the behaviour. Intervention is best directed at the reasons responsible for the behaviour, not the behaviour itself.
It then becomes only sensible to avoid the factors that contribute to these behaviours by correcting the conditions and the environments which ultimately lead to their expression. Fifty-five million years of evolution have designed the horse to thrive in a social environment, where the horse is foraging almost continuously and “on the move” to do so. Whenever these basic needs are not being met in the horse’s environment, the horse’s welfare suffers and the horse may develop seemingly “strange” and apparently irrational means to meet its biological programming. There are individuals amongst the general population who are particularly sensitive to the incompatibilities of stable-keeping practices and act as “canaries in the minefield.” These individuals are at a much greater risk for developing abnormal behaviours.
Prevention of stereotypic behaviours is key and must begin early in the life of a horse as the majority of these behaviours develops and becomes established before the horse is two or three years old. Early weaning practices and confinement housing of young horses create environments of social isolation and deprive the young horse of social interactions that shape and enrich its mental development. For many young horses, placement in a stable environment coincides with a change in feed type, physical location/housing, social environment, owners, and living conditions. Training expectations and workloads further compound and overwhelm the young horse. In order to cope with the physical and mental stressors imposed upon them many young horses develop stereotypies.
The domesticated horse housed in a stable may appear to be in an advantageous position over its feral cousins, for it is spared predation, hunger, thirst and harsh environmental elements. This sedentary and protected lifestyle may appeal to the logic and emotion of the human, yet the horses are demonstrating back to caretakers that the needs fundamental to their health and welfare are not being met. Although domestication frees the horse from many of the challenges it faces in its natural environment, it also presents adversities, difficulties and challenges unique to the horse’s nature. These include but are not limited to unnatural and/or processed feeds, meal feeding, a sedentary lifestyle, at times poor-quality housing i.e. lighting, ventilation, drafts, etc., athletic expectations, lack of socialization and inadequate environmental enrichment. When these unnatural — to the horse — challenges go unrecognized the horse’s welfare incurs hidden costs — one of which is undesirable behaviours.
As the horse’s caretaker, it is our responsibility to do the best we can to create living situations that are both physically and mentally healthy for the horse. In order to effectively problem solve the nature of abnormal behaviours in horses it becomes necessary to shift the burden of blame off the horse and direct it towards those responsible for the care of the horse.