PARENT SESSION
Contributed Oral Session 126: Mammal Ecology: Management, Reproduction, and Food Webs
Thursday, August 11, 8:00 AM - 11:30 AM, Meeting Room 524 C, Level 5, Palais des congrès de Montréal

Interference competition for water between elephants and other ungulates in a semi-arid savanna.

Valeix, Marion^{*,1, 1}, Fritz, Hervé, ¹ French National Centre for Scientific Research (CNRS), Beauvoir-sur-Niort, France

ABSTRACT- In semi-arid savannas where no natural permanent surface water is available, water is a key-resource and competition for this resource could play a major role in determining the structure of animal communities. In Hwange National Park, western Zimbabwe, the increase in the elephant population, which started in the mid 80s, has been correlated to decreases in some other ungulate populations. One major hypothesis suggests that competition for water between elephants and other herbivores could be the cause of some species decline. The regular 12 or 24 hour monitoring of different water pans in 2003 and 2004, which were two contrasted years in terms of rainfall, provides a good opportunity to preliminary test this hypothesis. Elephant sightings recorded during the drier year were twice those from the wetter year, and represented 57% of all the sightings. 64 aggressive interactions between elephants and other species were recorded in the wetter year contrasting with the 319 of the drier year. For some species, the time spent drinking depended on the number of elephants around the water pan. These preliminary results strengthen the hypothesis and provide useful information for water and megaherbivore management in protected areas.

Key words: competition, community, water, elephants