Ant communities and livestock grazing in the Great Basin, U.S.A.
Authors: M. S. Nash, W. G. Whitford, D. F. Bradford, S. E. Franson, A. C. Neale, and D. T. Heggem
Journal: Journal of Arid Environments
Summary of Methods: The effects of livestock grazing on ant species composition and diversity at two desert locations (eastern Idaho and southwest Utah) in the Great Basin were evaluated for one year. At each location study sites were categorized as good, fair, or poor range condition. Ants were captured from May 14-31 in Utah and from June 8-24 in Idaho. Ants were identified to species or taxonomic unit and populations of ant groups were calculated. Plant species richness and bare ground cover were also measured.
Article Summary / Main Points: Idaho had fewer ant species on rangelands in poor condition than poor condition rangelands in Utah. Overall rangelands in fair and good condition regardless of location had a greater variety of ant species than rangelands in poor condition. Community metrics for ants are poor indicators of rangeland conditions in the Great Basin.
Article Review Type: Refereed
Article Type: Experimental Research
Keywords: indicator, livestock grazing, ant, vegetation, bare patches, great basin, range condition, cool desert
Annotation: This was a replicated study, at two locations, over one season and the corresponding results apply to the Great Basin desert region. The lack of a relationship between ant communities and range condition suggest that more research is needed to determine whether ant community metrics can be viable indicators of range conditions in other locations. Because the research was limited to spring, a longer study period (i.e, spring through fall) may provide more useful information. A study conducted over several years may also reveal more consistent and reliable results. Nash et al. (2004, Ecological Indicators 4:199-213) also found that ant population metrics are poor indicators of grazing impacts on range quality in the Mojave Desert, available on the RSIS website.