PARENT SESSION
Oral Session #26: Conservation Ecology: Terrestrial.
Presiding: P. Kleintjes
Tuesday, August 6. 8:00 AM to 11:30 AM. Greenlee Meeting Room, TCC.
Artificial waterpoints influence wildlife distribution and vegetation in northern Botswana.
BARNES, MYRA*,1,2, 1 Carlsbad Caverns National Park, Carlsbad, NM2 New Mexico State University, Las Cruces, NM
ABSTRACT- Surface water limits the distribution of elephants and other water dependent animals in semi-arid savannas. In the Savuti area of Chobe National Park in Botswana, one artificial waterpoint (AWP) was installed in 1988 and two more were added in 1995 to attract wildlife in a popular tourist area. I measured growth and evidence of browsing by elephants and smaller ungulates to Acacia erioloba, an important shade and forage species, from 1994-1997 on plots from 2-10 km from AWPs. I also measured the amount of bark stripped from large canopy trees by elephants and recorded tree mortality annually. Mortality and severe browsing damage by elephants intensified in Savuti after the installation of two AWPs in 1995. Elephants pushed over or broke main stems from 22% of small A. erioloba trees in 1996 and 14% in 1997 on one plot within two km of an AWP where there was minimal evidence of elephant browsing prior to AWP installation. There was no evidence of A. erioloba recruitment or regeneration from 1994-1997 within 10 km of the three AWPs in Savuti. The mean circumference of bark stripped from mature canopy trees increased from 12% in 1994 to 36% after the AWPs were installed in 1995. Over 95% of bark circumference was removed from 13.6% of trees within 2 km of one artificial waterpoint in 1996. Results from this study suggest that providing artificial waterpoints in areas not previously used by elephants during the dry season increases browsing damage and tree mortality. While increasing the number of animals in tourist areas by providing additional water may be popular with park visitors, vegetation species that are less tolerant of elephant browsing may decrease or disappear from areas near the artificial water source.
KEY WORDS: elephant, Acacia erioloba, artificial waterpoint, Botswana