'Kick-Butt' Horses

Introduction

Each harem is made up of a harem stallion (one or two), his mares (five or six), and their offspring. The stallion’s ability to hold his mares together would determine the size of his harem. Therefore, it is of utmost importance to defend his harem against potential competitors trying to raid it. This is because a dominant stallion has elite rights to the mares in the harem; he may herd them by biting their necks, flanks, or hindquarters if they move too slowly. This is in line with his responsibilities to lead his harem to forage via communication signals. When leading stallions fight it out over mares, spectacular displays of rearing, biting, and kicking occur.




Social Hierarchy

Equine Tourism explains the significance of social hierarchy:

“Dominance hierarchy is essential for the ordering of social contacts. Establishing a clear social hierarchy means that each individual knows his position in the group, which leads to less aggression and more harmony. Internal fighting results in a loss of valuable energy and increases the chance of getting wounded - and survival in the wild requires much energy. Wounds attract parasites and can be the cause of dangerous if not lethal infections.”

The stallion articulates his dominant position by herding his mares, using a characteristic 'snaking' posture with his head held low and ears flat back. The mares settle their mutual disputes by lowering their ears and their neck and intimidating one another with bite threats or kicks with the hind legs.


An Encounter between Two Leading Stallions

Equine Tourism:

“An encounter between two leading stallions takes a ritualised course. The two dash into each other. Once they are close, they approach one another with crested necks and sniff noses. Mostly this will elicit a squeal and one or both may strike out with a front leg. Thereafter, they sniff at each other's genitals and noses. When a fight seems unavoidable, the opponents will rear and box with their front legs and bite one another fiercely in the flanks and legs. The hostilities will go on until the weaker party is chased away and the victor has rejoined his mares. However, most encounters between family stallions rarely end in violence. Encounters with mature bachelor stallions are far more hostile. Such confrontations are very violent and often lead to severe injury.”

In the course of many encounters the stallions learn to respect each other's force, and here is where communication signals are significant. These signals help them to decide whether they should avoid a particular harem stallion, or just take the opportunity to dispute a drinking place, or even mares.

Communication signals

Chemical Communication:

The harem stallion marks the urine of his mares with his own, letting other stallions know that these are his mares and also finding out which mares are in season. Dung piles are also a means of communication amongst the stallions. A stallion signals his presence and territorial space by marking a spot with his own dung. A passing stallion 'reads' the pile in a ritualised manner by sniffing the scent, moving over it, dropping his own dung and finally, sniffing his own freshly deposited scent markings. As a result, the stallion can ascertain whether other stallions passed by recently or at an earlier moment. Therefore, dung piles serve a social function in inter-harem communication and also function as an orientation marker.

There are also other communication methods in which the stallion establishes dominance over his mares, as in the following excerpt.

eNature on Audio and Visual Communication:

“The wild horse exhibits several vocalizations: snorts, which indicate danger and are used mostly by the stallion; neighs, which are a distress call, used mostly by the mare; nickers, for communication and courtship; squeals, used by the female when the male sniffs her genitalia, or by the male as a sign of aggression; and screams, the aggressive call of the male. The wild horse also has facial expressions. One is the greeting, in which the head is extended to touch another horse’s muzzle and lips; the greeting can change to the threat, in which the ears are directed backward, with the mouth possibly open as well. Another characteristic expression is the flehmen, in which the neck is extended and the upper lip curled, exposing the teeth; this expression is used by a stallion during pre-copulatory activity with a mare.”

Young Males- Future Leaders?

Usually, young males are forced out of the harem by the leading stallion before they can become a dangerous threat to him. A young male wards off attack by exhibiting a type of submissive behavior known as champing: moving toward the stallion, facing him nose to nose, with the ears in the upright (non-threatening) position. Young males could form bachelor herds with other males. Sometimes, young females leave their own harems to wander until they find an established harem to join or set up a new harem with a male. Thus a healthy population is maintained due to the prevention of inbreeding. In some cases, the leading stallion of a harem would let a strong young male stay on, as a potential successor.

References:

"Wild Horse", Michael H. Francis. eNature, 27 March 2008.

"Assateague National Seashore - Wild Horses", author unknown. GORP, 27 March 2008.

"Exploring the wild Przewalski Horses - Mongolia", author unknown. Equine Tourism, 27 March 2008.

For more information on domesticated stallion behavior, click here.