Behavioral Ecology and Sociobiology

, Volume 29, Issue 3, pp 217–219 | Cite as

Changes in herd stallions among feral horse bands and the absence of forced copulation and induced abortion

  • J. F. Kirkpatrick
  • J. W. TurnerJr.


Forced copulation and induced abortion were investigated in a herd of feral horses inhabiting a coastal barrier island. Eight mares were diagnosed pregnant in August and October 1989 by means of urinary and fecal steroid metabolites, prior to documented changes in herd stallions. These mares were observed for harassment and forced copulation by the new stallions and for the presence of foals during the spring and summer of 1990. No incidents of harassment or attempts at forced copulation were witnessed and seven of the eight mares produced foals in 1990. These data indicate that forced copulation and induced abortion are not common events among all feral horse herds and suggest reinvestigation of this hypothesized phenomenon.


Steroid Common Event Barrier Island Steroid Metabolite Fecal Steroid 
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Copyright information

© Springer-Verlag 1991

Authors and Affiliations

  • J. F. Kirkpatrick
    • 1
  • J. W. TurnerJr.
    • 2
  1. 1.Department of Biological SciencesEastern Montana CollegeBillingsUSA
  2. 2.Department of PhysiologyMedical College of OhioToledoUSA

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