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Pdf reprints of publications can be sent on request, or they can be downloaded from the link provided.
 
Bourjade, M., Tatin, L., King, S. R. B. & Feh, C. 2009. Early reproductive success, preceding bachelor ranks and their behavioural correlates in young Przewalski's stallions.
Ethology, Ecology and Evolution. In press.
Adult male dominance rank correlates with reproductive success in many mammalian species. Whether and how rank in immature males affects the number of offspring fathered later in life has rarely been investigated. Moreover, age, size and fighting skills all qualify as main intrinsic factors influencing rank, but mostly in sexually dimorphic species, where they may be interdependent. In a socially natural herd of Przewalski’s horses, a relatively monomorphic species, we explored (i) whether the dominance rank of young stallions living in a bachelor group was later associated with their reproductive success as young family holders, and (ii) whether higher ranking bachelors had a different behavioural profile to lower ranking ones in social interactions with peers. The stallions’ behaviour was observed during their bachelor period, from which dominance ranks and their behavioural correlates were established. Foal paternities were determined through genetic analyses. The number of foals sired by stallions before 7 years of age correlated positively with their rank position when they lived in a bachelor group. Social play and mutual grooming were the most frequent interactions exchanged between bachelors, regardless of their rank. Removing age effects: higher ranking stallions did not show higher physical aggression rates than lower ranking stallions, but the latter received more physical aggression from any other stallion, and lower ranking stallions engaged more often in stallion rituals than higher ranking stallions. This may show a propensity of subordinates for compromise rather than fighting.


Feh, C. & Munkhtuya, B. 2008. Male infanticide and paternity analyses in a socially natural
herd of Przewalski's horses: Sexual selection? Behavioural Processes. 78: 335-339.
The sexual selection hypothesis explains infanticide by males in many mammals. In our 11-year study, we investigated this hypothesis in a herd of Przewalski’s horses where we had witnessed infanticidal attacks. Infanticide was highly conditional and not simply linked to takeovers. Attacks occurred in only five of 39 cases following a takeover, and DNA paternity revealed that, although infanticidal stallions were not the genetic fathers in four cases out of five, stallions present at birth did not significantly attempt to kill unrelated foals. Infanticide did not reduce birth intervals; only in one case out of five was the infanticidal stallion, the father of the next foal; mothers whose foals were attacked subsequently avoided associating with infanticidal stallions. Therefore, evidence for the sexual selection hypothesis was weak. The “human disturbance” hypothesis received some support, as only zoo bred stallions which grew up in unnatural social groups attacked foals of mares which were pregnant during takeovers.

Reprints of this paper can be downloaded here


Tatin, L., Dutoit, T. & Feh, C. 2000. Impact du pâturage par les chevaux de Przewalski (Equus przewalskii) sur les populations d'orthoptères du Causse Méjean (Lozère, France). Revue d’Ecologie Terre et Vie. 55: 241-261.
La biologie de la conservation, en matière de gestion des espaces naturels, s'attache à créer de nouveaux écosystèmes ou à réhabiliter et restaurer les écosystèmes dégradés. Dans de nombreuses réserves naturelles, de grands herbivores sauvages ou rustiques sont utilisés afin de conserver certaines espèces ou habitats. Dans ce travail, nous avons testé l'hypothèse que le Cheval de Przewalski peut, au travers de son action de pâturage, créer un milieu différent de celui qui s'installe après abandon d'une pelouse calcaire pâturée par les ovins (Causse Méjean, Lozère, France). Une étude de la structure de la végétation et des caractéristiques du peuplement d'orthoptères a été menée selon que la pelouse était abandonnée ou pâturée par des chevaux de Przewalski. Trois faciès de végétation particuliers et six stations dans chacun d'eux ont été choisis. Au total, 180 m2 de pelouse ont été échantillonnés au biocénomètre pour les orthoptères et par la méthode des points quadrats pour la végétation. Des analyses multivariées (ACP, ordinations sous contraintes et AFC), des test ANOVA et une série de régressions linéaires nous ont permis de dégager et de hiérarchiser les facteurs les plus importants. Il apparaît que le pâturage à long terme crée un milieu plus ouvert et plus hétérogène du point de vue de la végétation. La pression de pâturage estimée pour les mois de juin et juillet 1998 agit essentiellement sur la densité de la strate de végétation la plus basse (0-5 cm). Seule la densité en orthoptères est affectée significativement. La valeur patrimoniale des espèces présentes uniquement dans la pelouse pâturée est discutée, ainsi que le rôle des refus et des lisières en tant que refuges. Aucun impact significatif de la pression de pâturage sur la diversité et l'équirépartition des peuplements d'orthoptères n'a été constaté.


Tatin, L., King, S. R. B., Munkhtuya, B., Hewison, A. J. M. & Feh, C. 2009. Demography
of a socially natural herd of Przewalski's horses: an example of a small, closed population.
Journal of Zoology. 277: 134-140.
Owing to habitat loss and fragmentation, large mammal populations all over the world are becoming increasingly small and isolated. It is therefore a conservation priority to understand mechanisms influencing the demography of such populations, which can easily be driven to extinction. The Przewalski’s horse Equus ferus przewalskii remains one of the world’s most endangered species and reintroduced animals are still vulnerable. Over 9 years, we analysed factors affecting mortality and female fecundity at the individual level in a predator-free, closed population of Przewalski’s horses, which grew from 11 to 55 individuals. Similar to other wild equids, the annual growth rate of the population was r=0.169. Typically, adult mortality was much lower than juvenile mortality, the latter being correlated with neither inbreeding coefficient of foals nor population density. We found no link between female fecundity and operational sex ratio of the herd, or inbreeding coefficient, lactation status and body condition of the mares. Although food therefore seemed not to be limiting in this population, density (number of horses ha-1 clearly reduced fecundity, especially in subadult mares. Thus, our results show that space can slow the growth rate of a population before resources become limited, a potential source of concern for increasingly shrinking habitats of endangered large mammals. Possible mechanisms causing this may be found in incest avoidance or other social parameters. Finally, in large herbivores, population density is said to exert influence in a sequential order: juvenile survival first, followed by fecundity of young females, then adult females, and adult survival last. Although we observed no link between density and juvenile survival in the studied population, our results otherwise support this hypothesis.

Reprints of this paper can be downloaded here


Post-graduate theses

Allen, S. 2007. Le cheval dans l'art paléolithique de la Dordogne : animation et comportement. Masters thesis. Université Libre de Bruxelles, Belgium.
L'étude porte sur l'art pariétal des grottes de Lascaux, des Combarelles, de Font-de-Gaume et de Gabillou (Dordogne, France). Elle a pour objectif de tirer des indications sur les sous-espèces d'équidés, l'âge, le sexe, la saisonnalité, mais surtout sur les comportements des chevaux représentés par les artistes paléolithiques. Le questionnement concerne les comportements les plus représentés pour chaque grotte et de manière générale. L'observation in situ et l'éthologie sont une aide précieuse pour l'établissement d'une base de données iconographiques, la création d'un répertoire comportemental et l'interprétation. La comparaison des chevaux sauvages observés dans la réalité et ceux figurés dans les grottes a permis de conclure de manière probante à la représentation et à la compréhension d'une majorité de thèmes comportementaux par les Hommes de la Préhistoire.

Bourjade, M. 2007. Sociogenèse et expression des comportements individuels et collectifs chez le cheval. Doctoral thesis. Université Louis Pasteur Strasbourg, France.
This study deals with the role of social influences on the regulation of social behaviour in horses. Our primary interest was how the social environment at early stages of development affected the development of social skills of young horses and its functional consequences on the early reproductive success of stallions. The results show that the behaviour of young Przewalski horses correlates with some features of their natal group, such as the young/adult ratio. Within families, the development of the young’s social preferences occurs with a differentiation of social relationships according to interacting partners. This suggests that both young and adult partners may constitute important and complementary social influences in the social development of young animals. Influences of an adult presence, tested in same-age domestic horses, reveal immediate effects on social relationships between young horses. These findings indicate interacting effects of the presences of young and adult partners in the young horses’ sociogeny. Additionally, a predictive link between stallion dominance rank in all-male groups and their subsequent paternities until six years old suggests there are important functional consequences of the development of male’s social skills. The second part of this study investigates decision-making processes in the collective movements of Przewalski horse families. Przewalski horses perform collective decisions in which adults contribute more than young horses, suggesting they have a better knowledge of their environment. Indeed, the social dynamics of movement patterns are affected by environmental factors and the horses make compromises between their own motivations and social cohesion. Overall, this study contributes to a better understanding of intra- and inter-generational social influences in animals, and their role in the acquisition of social skills in young horses and functioning of social groups.

Lardy, S. & Latapie, S. 2008. Morphometric study of Przewalski’s horses skulls in
collaboration with TAKH association. Doctorat Veterinaire. Faculty of Medicine de Creteil,
Ecole Nationale Veterinaire d’Alfort, France.
The Przewalski’s horse is the last wild horse of the world. Thanks to the zoo, it has been rescued from extinction. We worked in partnership with TAKH, an association which has contributed to the conservation of this species since 1990. The objective was to study twelve skulls of Przewalski’s horses, kept by the association, with the aim of listing possible abnormalities and to find out any relationship with the death of these animals. The observation and the description of teeth and jaws revealed many abnormalities, such as defects of teeth’s wear, malocclusion and deviation of mandibles and maxillary. The measurements of the angle of jaw’s deviation showed axial asymmetries, which were important for four skulls. Study of necropsy reports revealed that most horses were massively infested by internal parasites. The pointed parasitism and the abnormalities of teeth and jaws may be responsible for an important loss of weight and decline, then have contributed to death.

Munkhtuya, B. 2005. Behaviour and ecology implications for conservation of equid species in Mongolia. Ph.D. thesis. Charles University in Prague, Czech Republic.

Munkhtogtokh, D. 2007. Feeding preferences of reintroduced Przewalski mares. Magister thesis. Khovd University, Mongolia.

Samdanjigmed, T. 2008. Current situation of pasture usage and socioeconomy of herders of Khomiin Tal. Magister thesis. Khovd University, Mongolia.

Tsevelmaa B. 2008. Vegetation mapping of Khomiin Tal. Magister thesis. Khovd University, Mongolia.


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