Submitted to: Southwestern Naturalist
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/1/2002
Publication Date: 6/1/2002
Citation: SIPOS,M.P., ANDERSEN,M.C., WHITFORD,W.G. GOULD,W.R. GRAMINIVORY BY DIPODOMYS ORDII AND DIPODOMYS MERRIAMI ON FOUR SPECIES OF PERENNIAL GRASSES. SOUTHWESTERN NATURALIST. 2002. V. 47(2). P. 276-281.
Interpretive Summary: This study compared the rates of utilization of grasses by two species of kangaroo rats. Previous studies documented that one species of kangaroo rat utilized flowering tillers of desert grasses during the vegetative growth phase of the grasses. This study examined what species of grasses were preferred by kangaroo rats and what differences, if any, were characteristic of the kangaroo rat species. Kangaroo rats preferred the same species of grasses that are preferentially utilized by cattle. During periods of high kangaroo rat numbers, seed production by preferred grass species may be severely impacted and could contribute to rangeland degradation.
Technical Abstract: Kangaroo rats have been described as primarily granivorous; however, they also consume green vegetation. We investigated selectivity of grasses by kangaroo rats (Dipodomys ordii and D. merriami) presented with four common perennial grass species from the Jornada Basin in the Chihuahuan Desert. All grass species offered were utilized, and there were differences in utilization. Our results suggest that water content may underlie these differences, although other factors are not excluded. Merrian's kangaroo rats removed more tillers from each tussock of grass than Ord's kangaroo rat. Ord's kangaroo rat may select grasses with higher water content per tiller.