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in order to optimize production, range managers need to understand and manage the spatial distribution of free-ranging herbivores, although this task becomes increasingly difficult as ranching operations diversify to include management of wildlife for recreational hunting. White-tailed deer are sympatric with cattle throughout much of their range and are a valuable commodity in southern rangelands. The spatial distribution of deer and cattle was monitored over 1 year during four trials each lasting 12 days. In each trial six white-tailed deer (three bucks, three does) and nine cows were fitted with Global Positioning System (GPS) collars. Collars were scheduled to take a position location every 5 min to determine animal location. These data were analyzed to study animal-to-animal interactions. To minimize problems of spatial autocorrelation, data were thinned to hourly locations for assessing animal home ranges and distributions. Although there was extensive overlap in spatial distributions of deer and cattle the species exhibited strong temporal separation. The mechanism was probably a combination of avoidance of cattle by deer and different habitat requirements. Close interactions were rare, however, individual deer did not show avoidance of cattle until they were within 50 m of each other. Species distributions overlapped mainly on the most productive ecological sites such as clay loam soils and riparian areas which were favored by both species. Cattle avoided rocky terrain, so deer had almost exclusive use of rocky areas including the productive deep soil drainage areas within them. Does particularly favored these areas and the riparian areas while bucks favored the more open clay loam sites. In this shrub-dominated system both deer and cattle were often located close to ranch roads, and cattle especially used roads as paths of least resistance. Cattle were closely associated with water sources, but deer did not stay long near water or at supplemental feeding sites. Concerns that cattle will displace deer into marginal habitats, or that deer will over utilize vegetation near water and feeders, were not supported. Published by Elsevier B.V.