, Volume 45, Issue 4, pp 275–278 | Cite as

Intrapopulation differences in ant eating in the mountain gorillas of Bwindi Impenetrable National Park, Uganda

  • Jessica GanasEmail author
  • Martha M. Robbins
Short Communication


Variability in ant eating has been observed in several populations of eastern and western gorillas. We investigated the occurrence of ant (Dorylus sp.) eating in two groups of mountain gorillas (Gorilla beringei beringei) with overlapping home ranges within Bwindi Impenetrable National Park, Uganda from September 2001 to August 2002. We calculated the frequency of ant eating by an indirect method of analyzing fecal samples from silverbacks, adult females, and juveniles. One group consumed ants significantly more often than the other (3.3 vs 17.6% of days sampled). Furthermore, the group that consumed ants more often also consumed them on a seasonal basis (September–February monthly range: 0–8%; March–August monthly range: 30–42.9%). Finally, females and juveniles of this group consumed ants significantly more often than did the silverback (total samples containing ants: silverback, 2.1%; adult female, 13.2%; juvenile, 11.2%). Differences in ant eating between groups are likely due to variability in use of habitats where ants occur (particularly secondary forests). Surveys of ant densities in differing habitats, nutritional analysis of ants, and quantification of the amount of ants in their diets are necessary to understand if ant consumption is due to availability, nutritional value, group traditions, or taste preference.


Gorilla beringei beringei Ant eating Diet variability Age/sex differences 



We thank the Uganda Wildlife Authority and the Uganda National Council of Science and Technology for permission to conduct this research. We appreciate the hard work of the following field assistants: Philemon Agaba, Nkundah Fred, Nkwasibwe Champion, and Rukandema Purinari. Additional thanks go to Alastair McNeilage and the Institute of Tropical Forest Conservation for logistical help throughout the study, Beth Kaplin for support and advice, and Daniel Stahl for statistical guidance. This manuscript benefitted from the comments of Dr. Michael Huffman and one anonymous reviewer. This research was funded by the Max Planck Society.


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Copyright information

© Japan Monkey Centre and Springer-Verlag 2004

Authors and Affiliations

  1. 1.Max Planck Institute for Evolutionary AnthropologyLeipzigGermany

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