, Volume 54, Issue 1, pp 13–19 | Cite as

Integration of a hand-reared chimpanzee (Pan troglodytes) infant into a social group of conspecifics

  • Maria ThunströmEmail author
  • Tomas Persson
  • Mats Björklund
News and Perspectives


Rejections of infants among non-human primates occasionally occur in the wild as well as in captive settings. Controlled adoptions of orphans and introductions of individuals into new groups are therefore sometimes necessary in captivity. Consequently, behavioral research on integration procedures and on the acceptance of infants by adoptive mothers is much needed. In this study, the introduction and subsequent adoption were examined in an 18-month-old hand-reared chimpanzee (Pan troglodytes). The infant was introduced into an age/sex-diversified social group of conspecifics at Furuvik Zoo, Gävle, Sweden, and continuous focal data was collected during the final stage of integration, including infant care exhibited by the group members and the infant’s secure base behavior. The infant was successfully integrated into the group and engaged in positive social interactions with all group members. An adult primiparous female chimpanzee formed a bond resembling a mother–infant relationship with the infant, which continues to be maintained at publication. However, the female initially showed very limited interest in the infant. It was, in fact, two other younger female group members that exhibited most infant care. The infant’s secure base behavior patterns indicate that she adapted well to the new circumstances in the chimpanzee group as the integration progressed. This provides evidence that a final adopter does not necessarily initially show maternal interest and that there can be flexibility in maternal behavior in adult chimpanzee females. Moreover, the methods applied employing gradual familiarization with all the group members and the use of an integration enclosure, may have contributed to a successful result. These findings extend our knowledge of introduction procedures in captivity as well as provide information on foster mother–infant attachment in chimpanzees.


Integration Adoption Pan troglodytes Captive management Caregiving behavior Secure base 



We would like to thank Furuvik Zoo and Ing-Marie Persson for permission to conduct the study and for invaluable expertise. We are also grateful to the animal care staff at the zoo for their assistance. We also thank Mathias Osvath for his input in the beginning of the project as well as Björn Rogell and Paolo Innocenti for comments on the manuscript. Our appreciation is also extended to the reviewers, Kim Bard and Naruki Morimura. Research protocols reported in this article complied with the ethical standards in the treatment of the animals with the guidelines laid down by the Primate Society of Japan, NIH (US), EC Guide for animal experiments, as well as with all national institutional and government regulations regarding ethical treatment of our study subjects.

Supplementary material

10329_2012_319_MOESM1_ESM.jpg (507 kb)
Online Resource Photo to the left shows the integration enclosure (to the right in the photo) which is interconnected with the chimpanzee enclosures with an entry only the infant could fit through. The photo to the right shows how JF looks through the entry into the integration enclosure where the infant and the human caregiver were located during the four first weeks. (JPEG 507 kb)


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Copyright information

© Japan Monkey Centre and Springer 2012

Authors and Affiliations

  • Maria Thunström
    • 1
    Email author
  • Tomas Persson
    • 2
  • Mats Björklund
    • 1
  1. 1.Department of Animal Ecology, Evolutionary Biology CentreUppsala UniversityUppsalaSweden
  2. 2.Department of Philosophy, Lund University Primate Research Station FuruvikLund UniversityLundSweden

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