SELECTION OF REFUGE SITES BY SYMPATRIC MICROTUS-OCHROGASTER AND SIGMODON HISPIDUS

Prairie voles (Microtus ochrogaster) and cotton rats (Sigmodon hispidu s) are common, seasonally abundant members of communities of small mam mals in fields and meadows of northeastern Kansas. Despite being ecolo gically similar and mutually antagonistic, these two species coexist, even within the same small fields. Differences in microhabitat may fac ilitate this coexistence. I examined microhabitat use by evaluating se lection of refuge sites. Statistical analyses of a suite of microhabit at variables indicated that each species chooses sites in a nonrandom manner and that selected sites differ between the species in terms of vegetational and topographic attributes. Prairie voles choose refuge s ites with dense grass cover and a large amount of topographic relief r elative to randomly selected sites or to refuge sites of cotton rats; refuge sites of cotton rats have less ground cover but more tall forbs than do either randomly selected sites or refuge sites of prairie vol es.