Affiliative (af)

A review of literature on the social behaviour of horses is likely to lead many to think equine society is governed solely by the establishment of social hierarchies, usually based on the outcomes of social conflict or competition, commonly referred to as agonistic behaviour.

The description of animal societies is mainly based on agonistic classifications, in which cooperation and affiliative behaviour were overshadowed by the competition-aggression-reconciliation paradigm generally emphasized by many writers.

Affiliative interactions [af] refer to the activities between two or more (dyadic, triadic, poliadic) individuals within a social group with the function of developing, maintaining or enhancing social bonds. {Equus Ethogram Project}

Affiliative is from Medieval Latin; affiliatus, past participle of affiliare to adopt as a son, from Latin ad- + filius son

konik stallions mutual grooming

Indeed, agonistic and affiliative behaviour are inextricably intertwined (Price & Sloman, 1993) in the complexity of social interactions, making it a laborious task to filter away the units of behaviour neatly into separate compartments for either one type of interaction, or the other.

Social interactions lay on a behavioural continuum, a continuous stream of movements  (Fentress, 1990; MacNulty et al, 2007) or spectrums of behavior (Abrantes, 2011):

“The distinction between any two behaviour is a matter of function; the borderline separating one category from the other is a matter of observational skill, contextual parameters and convention; the way we understand it all is a matter of definition.” (Abrantes, 2011)

For instance, in the ‘Agonistic ethogram of the equid bachelor band’ published by McDonnell & Haviland (1994), agonistic encounters were considered based on their intensity, running or flowing across a spectrum from “very quiet affiliative behaviour to serious aggression” (McDonnell & Haviland, 1994).

In this Equus Ethogram Project, affiliative interactions will be classified separately from agonistic ones, at least when at all possible. A host of authors have extracted units of agonistic behaviours from the interwoven fabric of equine social interactions, so it should be likewise possible to extract those other units of behaviour which promote group cohesion: affiliative behaviours.

DSC03382

The results of a growing body of research on free-living mammals suggests that affiliative social interactions, those enhancing social bonds, have important fitness consequences for individuals ( Swedell, 2002; Weidt et al, 2007; Silk et al. 2003, 2010; Cameron et al. 2009; Frere et al. 2010; Wey & Blumstein 2012) engaged in them.

In horses as in most social mammals, affiliative interactions are usually described by mutual grooming, play and group resting. This ethogram considers including more subtle forms of affiliative behaviour, such as the frequency or duration one individual is found sharing close proximity with others as an indication of their level of bonding (Hinde 1976; Garai 1992; Kleindorfer &Wasser 2004).

This Equus Ethogram Project is an on-going work, and the general framework, or particular sections and pages will be updated as new light is shed or brought to our knowledge.

Cumberland Island horses WE

Species: Equus caballus

Subspecies/Breed/Type

Country: United States of America

Region/Province/Range: Georgia – Cumberland Island

Population type: Feral

Estimated Population size: about 170 horses (2010)

Management Authority: Cumberland Island National Seashore  National Park Service

Management Practices: Yearly Population Census

Details of Population

Horses have been on Cumberland Island at least since the 1700s. The current population however is likely the result of breeding with post-1900 introductions to the island. Genetic analysis has revealed that the horses on Cumberland Island resemble several current domestic breeds. (Goodloe et al, 1991)

This population is considered feral, free-ranging and unmanaged, with no supplementary feeding or veterinary care.

The park conducts a census every spring to monitor the population. Based on data from the last 12 years, the herd appears to be stable at approximately 175 animals. From 186 horses tallied in 1986, the population grew to about 220 horses in 1990. However, in 1991, 18% of the herd, about 40 horses, died as a result of an outbreak of eastern equine encephalitis. The latest census (2010) accounted for 121 horses. However, it generally considered that a further 50 horses where not accounted for in the 2010 census, and adding these would take the population to about 170 individuals.

Structure and demographics

Cumberland horses live in typical Harem formations and multi-stallion bands (n=37), all female groups (n=2) and a number of bachelor groups (Goodloe 1991). The mares to stallions ratio was 0.6 females:1.0 males (Goodloe 1991; Goodloe et al, 2000). Average multi-stallion band size was 4.6 horses. Up to 32% of the Cumberland Island Population was comprised of Sub-adults. 54% of stallions travelled in bachelor groups (Goodloe 1991; Goodloe et al, 2000)..

Issues worth noting and needed actions

Not applicable.


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Bibliography:

Goodloe, R. B. (1991) Immunocontraception, genetic management, and demography of feral horses on four eastern U.S. barrier islands. Ph.D. Thesis, Univ. Georgia, Athens. 150Pp

Goodloe, R. B. et al. (1991) Genetic Variation and its management applications in Eastern U.S. feral horses. J. Wildl. Manage. 55(3)

Goodloe, R.B., Warren, R.J., Osborn, D.A., and Hall, C. (2000) Population characteristics of feral horses on Cumberland Island and their management implications. The Journal of Wildlife Management, 64: 114-121.

Turner, M.G. (1987) Effects of grazing by feral horses, clipping, trampling, and burning on a Georgia salt marsh. Estuaries and Coasts, 10: 54-60.

Turner, M.G. (1988) Simulation and management implications of feral horse grazing on Cumberland Island, Georgia. J. Range Manage. 41:441- 447.


Further reading:

Position Paper: Wetland Impacts from Feral Horses, Cumberland Island National Shoreline

Wild Horses in a Georgia Wilderness? Cumberland Island National Seashore Completes Annual Count

Feral animals on Cumberland Island

Horses Gone Wild

Social Interactions (Si)

The importance of sociality to horses, Equus (ferus) caballus, is a topic that can never be emphasized strongly enough, their survival strategies and reproductive successes are highly dependent on the formation of cohesive social bonds (van Dierendonck, 2006 ). In fact, horses should not in my opinion be considered in any other context than a social one.

Tremendous effort has gone to describe the “workings” of the horse, how they behave and live, but many fail to see that living in close proximity with a con-specific has been shaped by millions of years of natural selection.

Despite millennia of domestication horses that have either been set free or have escaped and allowed to roam on their own accord, have in many parts of the world:  thrived by adopting survival and reproductive strategies that are generally quite similar to one another.

The fundamental similarities unveiled by years of descriptive studies are a testament to their evolutionary importance. But, similarities do not equate to sameness and differences found in their ways of life are likely to shed light on alternative life strategies, and their incredible biological plasticity which allows them to “fit” into such distinct environments.

It may be dead obvious to most that all extinct and extant equids are in fact horses. Equus, the name Linnaeus (1758) used to classify the genus that included the zebras, half-asses, donkeys, Przewalski and caballus, is a Latin name meaning: horse.

Throughout this Ethogram, emphasis is on Equus caballus, and use of the colloquial term “horse” is a shorthand referring exclusively to this species.

Studies of social behaviour are in fact studies of “(…) cooperation between individuals” (Tinbergen, 1953), and cooperation will be the centerpiece of our approximation to the social life of Equus caballus throughout this present work.

Just as organisms are communities of parts, so too societies are communities of individuals wherein cooperation, mating and the rearing of young play a vital role and in which individuals are driven by conflicting needs and interests. In other words, animal societies are characterized by cooperative and conflictive interactions among individuals: those between nearby con-specifics. (Whitehead, 2009)

It makes sense to consider that sociality brings about both ecological and genetic benefits to individuals by allowing them to better acquire and use certain resources, but group living has inherent costs too:

Increased foraging efficiency, improved predator detection, avoidance and defense, as well as easier access to reproductive options are three of the more important benefits of group living.

At the same time group living is likely to heighten competition for resources, aggression among group members, as well as increase exposure to parasites and disease. (Alexander, 1974) For social behaviour to be adaptive, advantages must outweigh the costs associated with group living (Alexander 1974; Wrangham & Rubenstein 1986).

Animals that live together influence each other in a myriad of ways, and serve a number of functions. In horse societies all individuals associate with all other individuals at some rate and any resulting order is related to the ecology of a population, including interactions with con-specifics.

Included under the section of Social Interactions, you will find the following subcategories:

  • Affiliative interactions (af)
  • Agonistic interactions (ag)
  • Communication (C)
  • Play (P)
  • Sexual (sx)
  • Parental (par)
  • Bonds (bd)
  • Roles (rls)

Huddling (hd)

A huddle is characterized by individuals crowding or gathering together. Most often, huddles are linked to thermoregulatory processes, and this social thermoregulation, or “(…) the ability of some species to use sociality or grouping to regulate their body temperature” (Gilbert, 2010), is a common energy saving strategy for many endothermic species (Canals, 1998; Alberts, 1978).

By bunching together, individuals reduce the body surface area exposed to inclement weather, consequently reducing energy spent in regaining a conservative equilibrium (Humphreys, 1933), or homoeostases.

In terms of horses huddling as a means of social thermoregulation, there really is very little work done. During cold weather horses have been observed to huddle or crowd together, on windy or rainy days; horses typically stand close to one another with “backs to weather” or “backs to natural windbreak”, as described by McDonnell (2003):

Backs to weather – Typically observed during windy or rainy days, Two or more horses stand closely together with their “(…) hindquarters into the wind.” (from the Equid Ethogram p. 79)

Backs to natural windbreak – Two or more horses stand closely together with their “(…) hindquarters protected from the wind by vegetation or other feature of the environment.” (from the Equid Ethogram p. 78)

McDonnell (2003), suggests that the backs to weather behaviour reduces the body surface area exposed to inclement weather, thus minimizing heat loss; in short it serves a thermoregulatory function.

In horses, the social bonds between unrelated mares, friendships, contribute to reproductive success as suggested by Cameron et al (2009) in a study on the Kaimanawa feral horses of New Zealand.

Horses have preferred partners within their band or herd with whom they associate more often with than other members of the group. Claudia Feh (1987), found that in the Camargue horses, horses had up to two, rarely three, preferred partners. These affiliative interactions are characterized by individuals sharing “personal space” (Dierendonck & Goodwin, 1992), and synchronizing activities.

Despite huddles not being extensively studied in horses, it is frequently mentioned in equid related literature, especially regards to group rest (Tyler, 1972; McDonnell, 2003; Ransom & Cade, 2009), or social grooming such as in mutual insect control. (McDonnell, 2003; Ransom & Cade, 2009)

Before going any further, let’s differentiate two types of huddles, namely; tight huddles and loose ones (Behnke, 2012). Tight huddles are those in which the majority of group members are in physical contact with one another, or separated by < 50 cms, leaving no gaps between individuals (Behnke, 2012). In contrast, loose huddles are those in which the majority of group members are in close proximity; from > 50 cms to < 150 cms, but not in physical contact with one another. Both between individual distances are currently in use in the ongoing Equus Ethogram Project.

Whether horses are grouped tightly or loosely may seem trivial, but for the sake of alienating the functional characteristics of different huddles, and their forms, the distances between individuals is likely of prime importance.

In tightly huddled horses, insect control is facilitated between group members. (Ransom & Cade, 2009) Several studies suggest that animals tend to group together when biting fly density or harassment is high (Bergerund, 1974; Schmidtmann and Valla, 1982; Rutberg, 1987; Rubenstein and Hohmann, 1989).

In the warmer months, which tend to correlate with an increase in insect harassment, two or more horses stand close together, typically tail to shoulder to the nearest neighbour. This is usually referred to as anti-parallel standing. In this position, individuals take advantage of one’s proximity to another to keep pesky biting insects at bay. Typically, horses have flies swished from their faces by the tail of a neighbour, but this can also be achieved by rubbing or bumping those close by.

Ingestive Behaviour (ing)

Under this heading we have classified behaviours related with taking material through the mouth and into the digestive system.

Horses are an herbivorous, grazing species that graze an average of 14-15 hours a day in the wild. Ronald Keiper (1985) found that horses on Assateague island spent 78% of daylight hours grazing. Horses are non-ruminants; they have a single stomach and the digestion of ingested roughage occurs in the cecum at the end of the large intestine. Cecal digestion, high level of food intake, and quick passage of food through the digestive system allows horses to have a diet high in fiber and low in protein.

Although horses prefer grasses (McDonnell, 2003), they are known to forage and derive nutrition from bark, tree, shrub buds, small woody stems, aquatic plants, fruits, roots and seeds (Hubbard and Hansen 1976; Varva and Sneva 1978; Salter 1978; Salter and Hudson 1979; Hanley and Hanley 1982; Krysl et al. 1984a). Feral and free ranging horses also pick food from the floor, and have been noted to glean and lick as well.

On Assateague Island along the Maryland-Virginia coast Keiper  (1985), found that these horses graze during 54.6% of the night time hours. Tyler (1972) in her 3 year study of the New Forest ponies stated; ‘from the few observations that were made at night, it seemed that most of the hours of darkness in all seasons were spent feeding’. From these studies it seems that on the onset of darkness walking and drinking activity becomes greater, especially in the first hours of darkness (Keiper, 1985).

Drinking in feral horses is not as frequent as one would expect, many only drink once or twice a day and some have been noted to travel considerable distances to drink once every 2 days. Drinking activity is variable in time and frequency and occurs both during day and night. (Pellegrini, 1971; Feist & McCullough, 1976) A direct correlation was observed between drinking frequency and ambient temperatures, with a clear increase in frequency occurring at temperatures above 30 C. (Crowell-Davis, 1985)

The category Ingestive Behaviour includes the following:

  • Suckling (sk)
  • Grazing (G)
  • Browsing (B)
  • Drinking (D)
  • Gleaning (gl)
  • Picking (pk)
  • Pica (Pc)
  • Corpography (cv)

Rest (Re)

Horses rest either standing or lying on the ground, and up to 30% of horse’s time budget can be spent resting. Rest in horses is generally a social and socially facilitated enterprise (see Group Rest), when one horse rests, others group members rest. Typically, in close proximity to other group members (Tyler, 1972; Feist & McCullough, 1976; Kimura, 1998; Sigurjonsdottir, 2003; Heitor et al, 2006), either in tight groups, or alternately, in groups of one or two pairs (Feist & McCullough, 1976).

However, foals were observed to rest together even though their mother’s were from different bands (Tyler, 1972).

Tyler (1972) observed seasonally different mean resting times in the New Forest ponies in her study. In winter daylight hours, adult ponies were observed to have 2-3 resting bouts lasting a mean length of about 40 minutes. Foals rested a little bit longer, about 44 minutes (Tyler, 1972). In summer, the length of resting bouts increased.

Not only did resting bouts increase in duration during the summer months, but New Forest ponies sought shelter in ‘shades’ (Tyler, 1972) for up to 5 hours.

Caging horses

Versión Español

Standard practice in the horse world dictates that horses be stabled, and provided with food, water and a place to rest. This minimalistic requirement for keeping horses in stables is a clear limiting factor for the horse’s expression of normal behavioral repertoires which undoubtedly compromises well-being and welfare.

A stall, whether you are selling vegetables in a local market, or using the same for confining your horse, usually refers to a small compartment. Small compartments for confining animals are referred to as cages.

Even the best of stalls are just glorified animal compartments, barren environments where horses are incapable of, or not allowed to, interact naturally with conspecifics or carry out the daily activities they would engage in, in free living or even enriched conditions.

This may be quite hard to digest for the majority of “naked apes”, as our life history is quite different to theirs.  With best intentions in mind, we confine them from extreme weather, keep them away from other horses that could potentially injure them, and lock them up for their own well-being, and of course our own peace of mind. We strive to feed them the best quality feed, usually the expensive stuff, based on counsel from professionals or even just because that is what has always been done.

Confinement in cages, stalls or even aquariums in most cases prevents animals from engaging in behaviors exhibited when living in free conditions and this in turn is well known to cause suffering and distress.

Band stallion mounting mare

Lately there has been a huge interest in improving the quality of life of captive and domestic animals which have led to the development of environmental enrichment, which in turn offer stimulation and opportunities to express species-specific behaviors.

An example from the father of Zoo Biology, Heini Hediger (1955), was an enrichment he provided in the Zurich Zoo to captive zebras.  During one of his trips to Africa, he noticed that many termite mound tops had been polished or rubbed away. Zebras would come along and rub themselves on these mounds as part of their grooming activities. In the zebra enclosure back in the Zurich Zoo, a cement make-believe termite mound was placed and the zebra were reported to be so excited by this enrichment that they rushed to it with such enthusiasm as to topple them over. Once these makeshift mounds were reinforced, Hediger reported that the mound “has been in daily use ever since” (Hediger, 1955).

On another note, Ernst Inhelder, a Swiss zoologist, studied species kept in impoverished or barren enclosures. He noted that animals kept in these conditions carried out repetitive stereotyped meaningless activities, such as walking back and forth a short distance, literally treading on their own footsteps.

Similar studies were carried out on laboratory animals and for example; rabbits were found to head sway, bite bars or walk in circles. (Morton et al., 1993). The same was true for birds (Morris,1966), carnivores (Fox, 1986), rodents (Baenninger, 1967; Wiedenmayer, 1987; Würbel et al., 1998; Callard et al., 2000; Reinhardt and Reinhardt, 2001a) and primates (Erwin and Deni, 1979; Poole, 1988; Harris, 1989).

In an attempt to improve conditions through cage size, Galef and Durlach (1993) as well as Bayne and McCully (1989), found that cage size does not necessarily reduce stereotypy. This is to be expected as it is the impoverished environment that is likely to be causing the stereotypies and not only the size of the cage.

Open stalls, or mini paddocks have been recently provisioned in many riding centers, precisely in an attempt to enrich the life of their horses. These open compartments are still barren and lack enrichment, especially of the social kind. But they are better than a kick in the bum!

A stereotypy is a ritualistic and repetitive type of behavior that serves no apparent function.  Here a quote from Katherine Houpt:

“For years, we’ve called behaviors like these stall or stable “vices.” The first part of the name is right—with the exception of fence-walking, a horse doesn’t do these things unless he’s in a stall. But the “vice” part isn’t correct, according to modern research, which indicates these actually aren’t bad habits per se, but simply the reactions of horses that aren’t getting what they need.” Katherine Houpt, from Stable Vice or Stereotypie?

Despite domestication, animals largely retain the basic behavioral repertoire of their wild counterparts. There is little evidence suggesting that the process of domestication has resulted in the loss of behaviors from the species specific repertoire (Price, 1999), or that basic motor patterns associated with the species repertoire have changed (Scott & Fuller, 1965; Hale, 1969; Miller, 1977).

“Domestic animals are sometimes provided with an environment that is physically similar to the habitat of their wild ancestors. Behavioral and physiological adaptations to such an environment will be readily achieved. Very often, however, the captive environment does not match the ancestral environment and adaptation is challenged. “ (Price,  1999)

It is no surprise that when these animals are taken out of their “boring”, isolated and rather barren confines most will react to novel stimuli with fearful or even aggressive behavior. It seems that horses “(…) show a compensatory increase in activity when released from their stalls (Houpt et al., 2001).

Social isolation is a disturbing experience for horses, and isolated subjects show behavioral and physiological stress reactions (Mal et al., 1991).

It is in the light of all exposed above that we must consider that horses confined or isolated in barren environments such as those of conventional battery stalls, or cages are insufficient in providing desirable behavioral well-being, as they cannot perform the majority of their species specific behavior, fleeing, engaging in normal social behavior, explore the environment, exercise or even graze or walk.

In the end, it is really up to you whether you decide to cage your horse or not.

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Quick-link to some of our posts:

Affiliative behavior in Equus caballus

Introduction

A review of literature on the social behavior of horses is likely to lead many to think equine society is governed solely by the establishment of social hierarchies, usually based on the outcomes of social conflict or competition, commonly referred to as agonistic behavior.

Agonistic interactions are social activities “related to fighting, whether aggression or conciliation and retreat.” (Wilson, 1975)

“Behavior patterns associated with fighting and retreat, such as attack, escape, threat, defense and appeasement.” (Slater, 1999)

The description of animal societies is mainly based on agonistic classifications, in which cooperation and affiliative behaviors were overshadowed by the competition-aggression-reconciliation paradigm generally emphasized by many writers.

Affiliative interactions refer to the activities between two or more (dyadic, triadic and so on) individuals within a social group with the function of developing, maintaining or enhancing social bonds. {Equus Ethogram Project}

konik stallions mutual grooming

Indeed, agonistic and affiliative behavior are inextricably intertwined (Price & Sloman, 1993) in the complexity of social interactions, making it a laborious task to filter away the units of behavior neatly into separate compartments for either one type of interaction, or the other.

Social interactions lay on a behavioral continuum, a continuous stream of movements  (Fentress, 1990; MacNulty et al, 2007) or spectrums of behavior (Abrantes, 2011):

“The distinction between any two behaviors is a matter of function; the borderline separating one category from the other is a matter of observational skill, contextual parameters and convention; the way we understand it all is a matter of definition.” (Abrantes, 2011)

For instance, in the ‘Agonistic ethogram of the equid bachelor band’ published by McDonnell & Haviland (1994), agonistic encounters were considered based on their intensity, running or flowing across a spectrum from “very quiet affiliative behavior to serious aggression” (McDonnell & Haviland, 1994).

In this Equus Ethogram Project, affiliative interactions will be classified separately from agonistic ones, at least when at all possible. A host of authors have extracted units of agonistic behaviors from the interwoven fabric of equine social interactions, so it should be likewise possible to extract those other units of behavior which promote group cohesion: affiliative behaviors.

DSC03382

The results of a growing body of research on free-living mammals suggests that affiliative social interactions, those enhancing social bonds, have important fitness consequences for individuals ( Swedell, 2002; Weidt et al, 2007; Silk et al. 2003, 2010; Cameron et al. 2009; Frere et al. 2010; Wey & Blumstein 2012) engaged in them.

In horses as in most social mammals, affiliative interactions are usually described by mutual grooming, play and group resting. This ethogram considers including more subtle forms of affiliative behavior, such as the frequency or duration one individual is found sharing close proximity with others as an indication of their level of bonding (Hinde 1976; Garai 1992; Kleindorfer &Wasser 2004).

This Equus Ethogram Project is an on-going work, and the general framework, or particular sections and pages will be updated as new light is shed or brought to our knowledge.

Quick-link to some of our posts:

A snippet on habituation

Habituation is one of those terms habitually (see I did it again) used in training and experimental protocols. Trouble is, it is so overused and underdefined that its significance has been frayed at the edges, and is used by most as a term that means having gotten used to something.

Whether you are training horses, dogs or rats, or working with these in laboratory or field experiments, the importance of habituation is underestimated in most cases.

Some proponents define habituation as a waning of response to repeated presentations of a single stimulus, while others would argue that it would only be so if the stimulus was not followed by a second reinforcing or punishing stimulus.

It is almost as if depending on your worldview and the justification you need for your methods or protocols, habituation per se would acquire a distinct definition in almost every case. Having said that most definitions are simplistic and vague in that they do not provide enough information for anyone to differentiate habituation from other phenomenon in which a waning of response is sought.

Habituation is a widespread occurrence, observed across phyla, from single cell organisms capable of behaviour, to mammals. The strikingly different neural and biochemical circuitry of the animals in which habituation has been described, underlie an elemental and nearly ubiquitous  form of biological plasticity , primal for survival and reproductive success in the majority of behaving organisms.

This same ubiquitousness however has led many to synonymously use the term instead of others whose underlying common denominator is a waning of response to repeated stimulus presentations such like acclimatization, accomodation, negative adaptation, desensitization, sensory or motor fatigue, extinction, or even inhibition, to name a few.

Even great trainers, that use scientifically backed knowledge are liable for mistakes in this sense. Let us take the example of this passage from the book; “Don’t Shoot the Dog” (Pryor, 2008), wherein habituation is used synonymously with the term extinguish, as follows:

“Habituation is a way to eliminate unconditioned responses. If a subject is exposed to an aversive stimulus that it cannot escape or avoid, and which nothing it does has any effect on, eventually its avoidance responses will extinguish.” (Pryor, 2008: p.121)

Going back to the passage from “Don’t Shoot the Dog” provided above, a closer look at the explanation of how habituation was apparently attained by exposure to aversive stimuli without possibility of escape, can equally refer to animals in a state of learned helplessness (Pryor, 2002: p.67)as explained in the very same book.

Furthermore according to Seligman (1992: p. 9) learned helplessness is “(…) a psychological state that frequently results when events are uncontrollable.” That is to say that if nothing the animal does can help it escape or avoid the aversive stimuli it plunges into learned helplessness.

All this is discussed in more detail in the Thesis I presented for the fullfilment of my obligations toward the Ethology Institute, and you can read the full thesis free online by following this link:

Habituation: An Ethological Approach

 

 

Herding behavior

Similar to  herdsmen or shepherd dogs herding their flocks of sheep, stallions herd or drive conspecifics  controlling their direction and speed, and this is usually referred to as herding or driving behavior (Tyler, 1972; Feist & McCullough, 1976; Lucy Rees, 1986; McDonnell, 2003).

Stallions have been observed to adopt a species specific herding posture (Berger, 1986) characterized by lowering their heads, stretching out their necks, pinning back their ears, and moving forward toward the targeted conspecifics. If we breakdown the herding posture to its component parts we would find a conglomerate of behaviors which may be interesting to consider on their own. The pinning in a backward direction of the ears, or Ears Laid Back (McDonnell, 2003), or Ears Retracted (Berger, 1986), is typical of a threat posture or expression (Tyler, 1972) as is the Head Threat (McDonnell, 2003) in which the head is pointed forward with neck extended and it is usually associated with agonistic encounters.

The targeted individuals typically responded by moving in the opposite direction from which the stallion was approaching. According to Tyler (1972), ocassionally the stallion would have to gallop in front of the group to ensure that mares did not straggle from the rest of the group in higher intensity movements.

The vigour or intensity of this behavior is assumed to correspond to how low the head is dropped and the general speed and gait adopted by the stallion. Not only that but how far ears are pinned in a backward position may also be indicative of intensity.

Additionally stallions may move the head from side to side in a snake-like fashion usually referred to as snaking movement, or head tossing (Berger, 1986). So, if a stallion approached with the herding posture at a walk, it was most common that the targeted conspecific/s would respond in a similar pace.

Stallions usually approached from the rear pushing the individuals forward, but they also approach from slightly to one side in order to direct movement.

Feist & McCullough (1976) observed this behavior in their study of the Pryor Mountain  feral horses of Montana. From a total of 139 instances wherein stallions were recorded to perfom this behavior, they noted that 42% (n=55) of these corresponded to stallions herding or driving their band away from other bands or stallions, in 30% (n=39) stallions where guiding the direction of movement of their bands while on the move, 12% (n=15) of the time stallions singled out a mare for courting, in 12% (n=15) stallions drove  non-band members away from theirs, and in the remaining 4% (n=6) stallions herded-in new members.

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If you are a photographer or happen to have images related to this topic, and wish to share them, please do contact us. We could surely use them, and would appreciate it greatly!

This is a work in progress under our ongoing Equus Ethogram Project, further information and suggestions are welcome and will contribute to further updates.

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Reference list

Berger, J. (1986) Wild Horses of the Great Basin The University of Chicago Press, Chicago, IL

Feist, J.D. and D.R. McCullough (1975) Reproduction in feral horses. J. Reprod. Fert., Suppl. 23:13–18.

Keiper, R. (1985) The Assateague Ponies. Tidewater Press, Cambridge, MD.

McDonnell, S.M. (2003). A practical field guide to horse behavior: The Equine Ethogram. Lanham,US.: The Blood-Horse, Inc.

Rees, L. (1984). The Horse’s Mind. London: Stanley Paul.

Tyler, S. .J (1972) The behaviour and social organization of the New Forest ponies. Anim. Behaviour Monographs 5 (2): 85-196.