Fighting back: Population recovery and expansion of the range size of the Mitumba chimpanzee community in Gombe National Park, Tanzania
- Published
- Accepted
- Subject Areas
- Animal Behavior, Anthropology
- Keywords
- chimpanzee, territoriality, Range expansion, Gombe
- Copyright
- © 2016 Mjungu et al.
- Licence
- This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, reproduction and adaptation in any medium and for any purpose provided that it is properly attributed. For attribution, the original author(s), title, publication source (PeerJ Preprints) and either DOI or URL of the article must be cited.
- Cite this article
- 2016. Fighting back: Population recovery and expansion of the range size of the Mitumba chimpanzee community in Gombe National Park, Tanzania. PeerJ Preprints 4:e1806v1 https://doi.org/10.7287/peerj.preprints.1806v1
Abstract
Chimpanzees (Pan troglodytes) compete aggressively for territory with their neighbors. Results from playback experiments and observations of naturally occurring intergroup interactions indicate that success in territorial competition depends mainly on the number of adult males on each side. Communities with more males are therefore expected to win more intergroup contests and, as a result, expand their range. Demography is thus expected to play a decisive role in intergroup competition. Testing this hypothesis, however, has proven difficult. Most studies have focused on a single community, so that the actual number of males is known for only one side. Additionally, because chimpanzees reproduce and grow slowly, many years of data are needed to test the effects of demographic change on territorial behavior. Here we report on 20 years of data from two habituated neighboring communities. We found that numerical advantage plays an important role in territorial competition. During the first part of the study period, the Mitumba community suffered a demographic decline. As a result, males from the larger Kasekela community won the majority of intergroup interactions and expanded their range deep into areas previously used by Mitumba. However, during the last five years, the Mitumba community increased in size, and subsequently recovered a substantial portion of their range from the Kasekela chimpanzees. This study highlights the importance of long-term studies for understanding territorial dynamics.
Author Comment
This is an abstract which has been accepted for the "Chimpanzees in Context" symposium.