Quantifying Equid Behavior—A Research Ethogram for Free-Roaming Feral Horses

For more information on the USGS—the Federal source for science about the Earth, its natural and living resources, natural hazards, and the environment, visit http://www.usgs.gov or call 1-888-ASK-USGS For an overview of USGS information products, including maps, imagery, and publications, To order this and other USGS information products, visit http://store.usgs.gov Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Although this report is in the public domain, permission must be secured from the individual copyright owners to reproduce any copyrighted materials contained within this report. Figures 1. Observed daytime activity budgets of adult control female feral horses and harem Introduction Feral horses (Equus caballus) are globally distributed in free-roaming populations on all continents except Ant-arctica and occupy a wide range of habitats including forest, grassland, desert, and montane environments. The largest populations occur in Australia and North America and have been the subject of scientific study for decades, yet guidelines and ethograms for feral horse behavioral research are largely absent in the scientific literature. The U.S. Geological Survey (USGS) Fort Collins Science Center conducted research on the influences of the immunocontraceptive porcine zona pellucida (PZP) on feral horse behavior from 2003–2006 in three discrete populations in the American west (see Ran-effort included over 1,800 hours of behavioral observations of 317 adult free-roaming feral horses. The following ethogram was developed during the course of this study to facilitate accurate scientific data collection on feral horse behavior, which is often challenging to quantify. By developing this set of discrete behavioral definitions and a set of strict research protocols, scientists were better able to address both applied questions, such as behavioral changes related to fertility control, and theoretical questions, such as understanding social networks and dominance hierarchies within social groups of equids.

[1]  Ronald R. Keiper,et al.  The stability of equine dominance hierarchies and the effects of kinship, proximity and foaling status on hierarchy rank , 1986 .

[2]  J. Fahnestock,et al.  The influence of herbivory on plant cover and species composition in the Pryor Mountain Wild Horse Range, USA , 1999, Plant Ecology.

[3]  S. Wilson,et al.  Behavioral sampling techniques for feedlot cattle. , 2001, Journal of animal science.

[4]  David A. Elston,et al.  ASSESSMENT OF PREFERENCE AMONG A RANGE OF OPTIONS USING LOG RATIO ANALYSIS , 1996 .

[5]  R. Tausch,et al.  Multi-scale responses of vegetation to removal of horse grazing from Great Basin (USA) mountain ranges , 2008, Plant Ecology.

[6]  V. Klimov.  Spatial-ethological organization of the herd of Przewalski horses (Equus przewalskii) in Askania-Nova , 1988 .

[7]  L. Eberhardt,et al.  Growth Rates of Feral Horse Populations , 1991 .

[8]  R. B. Srygley,et al.  Behavioral ecology of the Jeju pony (Equus caballus): Effects of maternal age, maternal dominance hierarchy and foal age on mare aggression , 2004, Ecological Research.

[9]  D. McCullough,et al.  Behavior patterns and communication in feral horses. , 2010, Zeitschrift fur Tierpsychologie.

[10]  W. Sutherland,et al.  The importance of behavioural studies in conservation biology , 1998, Animal Behaviour.

[11]  P. Moehlman.  Equids: Zebras, Asses and Horses. Status Survey and Conservation Action Plan edited by Patricia D. Moehlman (2002), ix + 190 pp., IUCN/SSC Equid Specialist Group, IUCN, Gland, Switzerland and Cambridge, UK. ISBN 2 8317 0647 5 (pbk), unpriced. , 2003, Oryx.

[12]  Shin Ta Liu,et al.  Permutation Methods: A Distance Function Approach , 2002, Technometrics.

[13]  Ronald R. Keiper,et al.  The Position of the Stallion in the Equine Dominance Hierarchy of Feral and Domestic Ponies , 1982 .

[14]  Daniel I. Rubenstein,et al.  Horse signals: The sounds and scents of fury , 1992, Evolutionary Ecology.

[15]  K. Nankervis,et al.  Equine Behaviour: Principles and Practice , 1998 .

[16]  S. Crowell‐Davis.  Sexual behavior of mares , 2007, Hormones and Behavior.

[17]  B. Colenbrander,et al.  Differences in social behaviour between late pregnant, post-partum and barren mares in a herd of Icelandic horses , 2004 .

[18]  N Thompson Hobbs,et al.  Alternatives to statistical hypothesis testing in ecology: a guide to self teaching. , 2006, Ecological applications : a publication of the Ecological Society of America.

[19]  R. Buchholz.  Behavioural biology: an effective and relevant conservation tool. , 2007, Trends in ecology & evolution.

[20]  William E. Jones,et al.  The Veterinary Clinics of North America , 2003 .

[21]  W. D. McCort.  Behavior of Feral Horses and Ponies , 1984 .

[22]  LEONARD A. BRENNAN,et al.  COMPARISON OF TYPE I ERROR RATES FOR STATISTICAL ANALYSES OF RESOURCE SELECTION , 2004 .

[23]  Caudle,et al.  Aggression and social spacing in light horse (Equus caballus) mares and foals. , 2000, Applied animal behaviour science.

[24]  W. Klemm,et al.  Variations of Equine Urinary Volatile Compounds during the Oestrous Cycle , 1997, Veterinary Research Communications.

[25]  Ronald R. Keiper,et al.  Social interactions of free-ranging Przewalski horses in semi-reserves in the Netherlands , 1992 .

[26]  R. Garrott,et al.  Dynamics of a Feral Horse Population in Montana , 1990 .

[27]  J. Wilcox,et al.  Apparent rates of increase for two feral horse herds , 1982 .

[28]  V. Nettles.  Potential consequences and problems with wildlife contraceptives. , 1997, Reproduction, fertility, and development.

[29]  J. Aitchison.  On criteria for measures of compositional difference , 1992 .

[30]  H. Klingel.  Social organization and reproduction in equids. , 1975, Journal of reproduction and fertility. Supplement.

[31]  Rachel Petrik,et al.  Indirect Effects of Feral Horses on Estuarine Communities , 2002 .

[32]  R. Estes.  THE ROLE OF THE VOMERONASAL ORGAN IN MAMMALIAN REPRODUCTION , 1972 .

[33]  P. Guttorp,et al.  Statistical Interpretation of Species Composition , 2001 .

[34]  K. Houpt,et al.  DOMINANCE HIERARCHIES IN DOMESTIC HORSES , 1978 .

[35]  K. Houpt,et al.  The role of the Flehmen response in the behavioral repertoire of the stallion , 1989, Physiology & Behavior.

[36]  M. L. Wolfe,et al.  Reproductive rates of feral horses and burros , 1989 .

[37]  K. Houpt,et al.  MUTUAL GROOMING AND NEAREST-NEIGHBOR RELATIONSHIPS AMONG FOALS OF EQUUS CABALLUS , 1986 .

[38]  D. Rubenstein.  Life history and social organization in arid adapted ungulates , 1989 .

[39]  M. Oom,et al.  Social relationships in a herd of Sorraia horses Part I. Correlates of social dominance and contexts of aggression , 2006, Behavioural Processes.

[40]  P. Mielke,et al.  Permutation Methods: A Distance Function Approach , 2007 .

[41]  D. Doran,et al.  Comparison of instantaneous and locomotor bout sampling methods: a case study of adult male chimpanzee locomotor behavior and substrate use. , 1992, American journal of physical anthropology.

[42]  R. Tilson,et al.  Buddies and bullies: Social structure of a bachelor group of Przewalski horses , 1988 .

[43]  J. Herrick,et al.  Effects of feral horses in Great Basin landscapes on soils and ants: Direct and indirect mechanisms , 2006 .

[44]  S. Shen,et al.  The statistical analysis of compositional data , 1983 .

[45]  R. Terry Bowyer,et al.  Costs and Benefits of Group Living in a Recently Social Ungulate: The Alaskan Moose , 1994 .

[46]  Time-budget data : log-linear and analysis of variance compared , 1992 .