The Basics of Equine Behavior

Published 7/22/2004

Carey A. Williams, Ph.D., Extension Specialist in Equine Management

Ten Natural Survival Traits

1. The horse, a prey animal, depends on flight as its primary means of survival. Its natural predators are large animals such as cougars, wolves, or bears, so its ability to outrun these predators is critical. As humans, we need to understand their natural flightiness in order to fully understand horses.
2. Horses are one of the most perceptive of all domestic animals. Since they are a prey species, they must be able to detect predators. A stimulus unnoticed by humans is often cause for alarm for horses; as riders and trainers we commonly mistake this reaction for “spookiness” or bad behavior.
3. The horse has a very fast response time. A prey animal must react instantly to a perceived predator to be able to survive.
4. Horses can be desensitized from frightening stimuli. They need to learn quickly what is harmful (e.g., lion, cougar, etc.) and what is harmless (e.g., tumbleweeds, birds, a discolored rock, etc.), so they do not spend their whole lives running away.
5. Horses forgive, but do not forget. They especially remember bad situations! This is why it is critical to make the horse’s first training experience a positive one.
6. Horses categorize most experiences in one of two ways: a) something not to fear, so ignore or explore it, and b) something to fear, so flee. Therefore, when presenting anything new, the horse needs to be shown that ‘a’ is the case. Again, it is important to make all training experiences positive.
7. Horses are easily dominated. The horse is a herd animal where a dominance hierarchy is always established. If done correctly, human dominance can easily be established during training without causing the horse to become excessively fearful.
8. Horses exert dominance by controlling the movement of their peers. Horses accept dominance when: a) we or another animal cause them to move when they prefer not to, and b) we or another animal inhibit movement when they want to flee. Examples include using a round pen, longe line, or hobbles; or the more dominant horse in the field chasing the less dominant one away.
9. The body language of a horse is unique to the equine species. As a highly social animal, the horse communicates its emotions and intents to its herd mates through both vocalization and body language. A person handling horses needs to be able to read the horse’s body language to be an effective trainer.
10. The horse is a precocial species, meaning that the newborn foals are neurologically mature at birth. They are most vulnerable immediately after birth so they must be able to identify danger and flee if necessary.

Senses

A horse’s vision is its primary detector of danger. Even though they have poor color vision, they can differentiate blue and red from gray hues. However, they have more trouble differentiating yellow and green from gray. Horses also have poor depth perception when only using one eye. They can’t tell a trailer from an endless tunnel, or a mud puddle from a bottomless lagoon. Their perception is improved by about 5 times when using both eyes (binocular vision). They can instantly change their focus from near to far objects. This is why horses cock their head in different ways to see close vs. distant objects. Horses have an acute ability to detect movement. This is why a horse is much flightier on windy days; things that are normally stationary are now moving and perceived as a potential threat. Horses are able to see fairly well at night; however, the contrast sensitivity is less than that of a cat.

The mechanics of a horse’s vision are different from our own. They can see almost panoramically, with a small spot directly in front and directly behind as their blind area (see Figure 1). Never approach a horse without talking to them in these areas; if frightened they will use one of their defense mechanisms, e.g., kick or run. A horse can see two things at once, one from each eye. That allows each side of its brain to work separately. Like humans, horses have a dominant side (right-handed or left-handed); however, unlike humans, horses need to be taught things twice: on the right side and on the left side. The expression in a horse’s eye is often thought to be a good indicator of their behavior, e.g., wide open with white showing (and not an Appaloosa), scared; half closed, sleepy, etc.

A horse’s hearing is much keener than ours. They use their hearing for three primary functions: to detect sounds, to determine the location of the sound, and to provide sensory information that allows the horse to recognize the identity of these sources. Horses can hear low to very high frequency sound, in the range of 14 Hz to 25 kHz (human range = 20 Hz to 20 kHz). Horses’ ears can move 180 degrees using 10 different muscles (vs. 3 for the human ear) and are able to single out a specific area to listen to. This allows the horse to orient itself toward the sounds to be able to determine what is making the noise.

Horses’ tactile sensation or touch is extremely sensitive. Their entire body is as sensitive as our fingertips. They can feel a fly on one single hair and any movement of the rider.

Body Signals
Horses are good at letting us know exactly how they are feeling; the only problem is most people don’t know how to speak “horse”. So here are some tips on reading a horse’s body language.

If a horse’s tail is:

• High: they are alert or excited
• Low: it is a sign of exhaustion, fear, pain or submission
• Held high over its back: (as seen in most foals) they are playful or are very alarmed
• Swishing: they are irritated.

If a horse’s legs are:

• Pawing: they are frustrated
• One front-leg lifted: can be a mild threat (or a normal stance sometimes when eating
• A back-leg lifted: is often a more defensive threat
• Stamping: indicates a mild threat or protest (or they may be getting rid of insects or flies biting their legs).

Some horses’ facial expressions include:

• Snapping: This is seen in foals showing submission to an older horse. They will open their mouths and draw back the corners, then open and shut their jaws.
• Jaws open with teeth exposed: this shows aggression or possible attack.
• The Flehmen response: This is caused by an intense or unusual smell, usually in stallions when they sense a mare in heat. They stick their nose in the air and curl the upper lip over their nose.
• Flared nostrils: usually means they are excited or alert.
• Showing white around the eyes: usually means they are angry or scared. (White around the eyes is also a normal characteristic of the Appaloosa breed.)

The horses’ ears are a unique feature:

• Neutral: is when the ears are held loosely upward, openings facing forward or outward.
• Pricked: ears held stiff with openings pointed directly forward means the horse is alert.
• Airplane ears: the ears flop out laterally with openings facing down, usually meaning the horse is tired or depressed.
• Drooped ears: hang down loosely to the side, usually meaning tiredness or pain.
• Ears angled backward (with openings directed back towards a rider): usually mean attentiveness to the rider or listening to commands.
• Ears pinned flat against the neck: (see picture below) the means watch out! The horse is angry and aggressive.

Communication
Horses have a variety of methods of vocal and non-vocal communication. Vocal noises include a squeal or scream which usually denotes a threat by a stallion or mare. Nickers are low-pitched and quiet. A stallion will nicker when courting a mare; a mare and foal nicker to each other; and domestic horses nicker for food. Neighs or whinnies are the most familiar: high pitched, drawn out sounds that can carry over distances. Horses whinny to let others know where they are and to try to locate a herd mate. They also respond to each other’s whinnies even when out of sight.

Blowing is a strong, rapid expulsion of air resulting in a high pitched “whooshing” sound, which usually is a sign of alarm used to warn others. Snorting is a more passive, shorter lower pitched version of blowing and is usually just a result of objects entering the nasal passage.

In contrast to signals of aggression within a herd, there are also signs of friendship. Mares and foals nudge and nuzzle each other during nursing or for comfort, and mutual grooming, when two horses nibble at each other, is often seen.

Social Structure

A herd of wild horses consists of one or two stallions, a group of mares, and their foals. The leader of the herd is usually an older mare (the “alpha mare”), even though one stallion owns the herd. She maintains her dominant role even though she may be physically weaker than the others. The older mare has had more experiences, more close encounters, and survived more threats then any other horse in the herd. The requirement of the lead horse is not strength or size; if this were so, then humans could never dominate a horse. Dominance is established not only through aggression but also through attitudes that let the other horses know she expects to be obeyed.

The stallion’s job is to be the herd’s guardian and protector, while maintaining reproductive viability. The stallion’s harem usually consists of 2 to 21 horses, with up to 8 of those being mares and the rest their offspring. When the colts are old enough to be on their own they will form a bachelor herd. The fillies will either remain in their natural herd or more commonly disperse into other herds or form a new herd with a bachelor stallion. As soon as a stallion becomes too old to maintain his status as herd owner he is replaced by a younger stallion from a bachelor herd. The average time for a stallion to remain leader is about 2 years, but some can last more than 10 years.

Horses are most vulnerable when they are eating or drinking. So, when a horse is being submissive, it will simulate eating by lowering its head, chewing, and licking its lips (similar to snapping mentioned above). Dominance occurs when a horse forces the other to move against its will. One horse will move its body in the direction of or in contact with the other forcing it to move. Fighting usually occurs when the dominant horse is challenged by the other horse not moving, or responding aggressively.

Vices

Vices are negative activities that occur due to various causes, including stress, boredom, fear, excess energy, and nervousness. Horses naturally graze for 12 to 16 hours a day. When kept in stalls we prevent them from engaging in many natural activities such as grazing, walking, or playing with other horses. Not enough natural stimuli will cause a horse to invent its own stimuli. Once these habits start they are difficult to eliminate.

Cribbing occurs when the horse bites onto a fixed surface (e.g., stall door edge, grain bin, fence rail), arches his neck and sucks in air, making a grunting noise. This causes a release of endorphins which relieves the unpleasant situation. Cribbing becomes addictive; even when removed from the unpleasant situation the horse may still crib. Some horses even prefer cribbing to eating! Cribbing can lead to weight loss, poor performance, gastric colic, and excessive tooth wear.

Weaving occurs when the horse stands by the stall door and rhythmically shifts its weight back and forth on its front legs while swinging its head. This is also caused by boredom or excess energy, and can lead to weight loss, poor performance and weakened tendons.

Stall kicking, stall walking, pawing, or digging, and biting over the stall door are also vices that are caused by boredom from being kept in a stall. To decrease the frequency of this behavior, you might try adding another mealtime, placing toys in the stall, or providing more roughage or turn out time.

Wood chewing, eating bedding, or dirt, and self-mutilation are caused by lack of exercise or boredom. However, nutritional deficiencies could also cause these vices. To eliminate this as a cause, provide more roughage to the diet, and free choice salt or minerals. This may decrease the frequency of the vice.

References
Keiper, R.R. 1986. Social Structure. Veterinary Clinics
of North America-Equine  Practice. 2: 465-484.

McDonnell, S. Equine Behavior Lab, University of Pennsylvania,
School of Veterinary Medicine.
www2.vet.upenn.edu/labs/equinebehavior/

Miller, R.M. 1995 to 1997. Behavior of the Horse.
Journal Equine Veterinary Science. Volume 15(1) to Volume 17(4).

Timney, B., and T. Macuda. 2001. Vision and Hearing
in Horses. Journal of American Veterinary Medical
Association. 218:1567-1574.