Q: Why is The Equid Ethogram such an important work for students of horse behavior?

A: The Equid Ethogram serves to inform anyone interested in horse behavior, from youngsters to established scientists, of the standard nomenclature and existing field studies that can serve as resources for more detailed information. English is becoming the international language of science, so this book is a particularly useful and concise summary of the accepted terminology and nomenclature for the behavior of the species, consistent with those for general animal behavior.

For students of general animal behavior, animal science, or equine science, this book will improve efficiency by providing concise references to the existing scientific literature. No need to re-do the search. Beyond equine behavior, the horse is a good model species that interests and excites students. Many students these days relate better to a familiar domestic mammal than to an insect or laboratory rodent.

The field guide is also an excellent teaching tool for introducing the organization and discipline of descriptive animal behavior. As much as providing answers to students, this book stimulates questions, for both descriptive and experimental studies. There is nothing more motivating or useful in bringing out the natural scientist in new students than helping them to come up with their “own” questions. The information in this book (and on a smaller scale in the past) has proven to be a great tool for stimulating excellent questions from beginning research students.

An outstanding field laboratory exercise for any group, from pony club to graduate students, is to take this field guide out to watch horses -- domestic, feral, or semi-feral, whatever -- and to look up each observed behavior. This activity reliably stimulates genuine scientific questions.

Q: How is the book important -- and useful -- for regular horse owners?

A: In this era of growing interest in horse behavior, this discipline has become a minefield of misinformation about natural, normal horse behavior. Many of the popular "horse behavior" gurus simply perpetuate myths and fabricate interpretations, names, and information about natural horse behavior and its relationship to domestic horse handling, training, and problem management. This book provides a scientifically sound reference to behavior nomenclature and terminology in a user-friendly format. As a reference, it is equivalent to a field guide to bird behavior and is useful at any level of "horse watching."

Q: What drew you into the field of horse behavior?

A: I was trained at the bachelor’s and master’s level as a clinical and experimental psychologist and was studying behavior of mammals in general for a Ph.D. when the opportunity arose to use sexual behavior dysfunction in stallions as a model for basic and applied research.

Q: Tell us about the semi-feral herd of horses you maintain at the New Bolton Center in Pennsylvania.

A: Most of the original observations supporting this field guide were conducted within the context of the semi-feral herd of Shetland-type ponies that resides at the New Bolton Center of the University of Pennsylvania School of Veterinary Medicine. This herd was started by assembling a group of mature pony mares and stallions obtained from local auctions and farms. They have been maintained there since 1994 with minimal intervention and serve primarily as a living laboratory readily available year-round for study of physiology and behavior. They also serve as an educational resource for veterinary and animal behavior students and, on a limited basis, the seriously interested horse-owning public. The herd includes multiple harem groups with foals, yearlings, and some young adult offspring, as well as bachelor and young juvenile groups. Because the herd quickly grew to fill the available acreage, it has been maintained at between 50 and 75 animals. As necessary, entire family groups are separated from the main herd and are then gently introduced to the domestic environment before eventually ending up as ordinary domestic ponies.

Q: In what ways has this herd contributed to your research?

A: Our main research reason for having this herd is to answer questions about social effects on reproductive function. And most of our work concerns stallions. Questions like who gets to be a harem stallion, and who gets to be a bachelor? And then, of course, we are interested in how our findings relate to domestic horses and breeding. Beyond those basic and applied research questions, the herd has been a ready resource for all sorts of descriptive behavior studies.

Natural descriptive studies have been done on a number of semi-feral and wild equid populations, but due to obvious limitations, on a much more limited basis. The beauty of this semi-feral system right here on our rural campus is that we know so much more about these particular individual animals, most of them since birth, and can appreciate the variation in behavior over time and season. Longitudinal year-round daily observation of an entire herd, with several harems and a bachelor band, is unique in the study of horse behavior and fairly rare in the study of any animal species. And so work from this herd, though just one population, can "fill in the many blanks" from reports of studies in the wild, which are so often limited to particular seasons, or to particular segments of the herd. There are obvious limitations with this herd -- most importantly, they are not exactly wild. But their behavior is so consistent with what we know about truly wild herds, that we believe the trade-off is okay.

Q: How do you go about observing the herd? How much interaction do you have with the horses?

A: Our research with this herd has been a mix of mostly observational contact with some periodic physiologic sampling. The observational work is by design conducted from a distance -- so there is no contact that would disturb ongoing behavior. We have observation platforms throughout the habitat, and some observations are done from a field vehicle or on foot at a distance that does not disturb ongoing behavior, yet facilitates direct observation of whatever behavior we are studying at the time, sometimes with the aid of binoculars or long camera lenses. The physiologic measures are also done in a manner that minimizes human contact and stress. Animals have been trained to tolerate measurements and sampling, and so can be approached and handled when necessary with minimal restraint and disturbance. Sometimes groups are momentarily contained in smaller enclosures for these measures.

Depending upon the study, and particular behavior of interest, we use hand-held computer event-recorders or customized time-based check sheets which enable detailed recording of the occurrence, duration, and associations of various behaviors. Some behaviors can be sampled in three-hour blocks equally representing the daylight hours. We have also had occasion to sample continuously 24-hours a day using a team of observers, and we have done time and motion studies to compare the activity or "time budgets" of herd members of various sex, age, and social status throughout the day and around the various seasons of the year.

We also maintain daily "herd maps" on which we indicate general social organization and use of the environment and resources; in other words, "Where is each animal and who's with whom." This daily record also records all observed breedings, foalings, group membership changes, observed disturbances, between-band dominance order over resources, etc. We record periodic weights (girth tape measured estimates) and heights, body condition score, body maps with any minor blemishes, any injuries (very rare), hoof condition, teeth condition, etc. These are all evaluated according to social categories, groups, ages, sex, etc.

Q: Have you been surprised at certain behaviors you've seen?

A: There’s always a surprise, which speaks to the variation and richness of horse behavior. A good example would be the extraordinarily complex parenting behavior of stallions. Before studying horses so closely under natural social conditions, observers had thought that the mare was the principal parent of foals. That’s because many of the studies had been done with mare and foal groups on farms (no stallions). And under truly wild conditions, the observer is an intruder representing a threat of sorts. The stallion’s primary job is vigilance and protection of the herd. When there is an intruder, the stallion’s priority appears to be defense, and the foals return to the mares for care and protection. But since this herd has become accustomed to us observers, it can usually relax with us. And when the horses do relax, we see that the stallions do much of the parenting once the foals are a couple weeks of age. They play with juveniles, retrieve them when they wander off, and if you tally up the time devoted to care of young, stallions typically do as much or more than mares. The mares, of course, are the source of early nutrition, but the nursing time is lower than the stallion parenting activities. Some really touching surprises include individual interactions, such as stallions vocalizing to foals during birth and nuzzling the foal, effectively removing the membranes during birth. These are moments we always remember.

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