Influence of kangaroo rat burrows in the spatial organization of the San Jose Island rodent community

Knowledge of the spatial distribution of rodents around kangaroo rat burrows may help us to understand the role that kangaroo rats play in the spatial organization of small desert rodent communities. In this study we analyzed the pattern of proximity between capture locations of desert rodents and burrows of Dipodomys merriami insularis, and describe the reproductive characteristics of these rodents. Captures and recaptures of individuals were carried out in an area of 79.8 ha on Isla San José in the Gulf of California, Mexico, during March to May and October to November of 2008. In order of decreasing frequency, Chaetodipus spinatus bryanti, D. m. insularis, Peromyscus fraterculus cinereus, and Neotoma bryanti bryanti were captured during both periods. The results provide evidence that the spatial distribution of these rodents around D. m. insularis burrows varies with sex and reproductive activity of the kangaroo rats. They suggest that female and male kangaroo rats have a different influence on the spatial organization of the rodent community on Isla San José. Furthermore, this study provides information that should improve our understanding of the island rodent community, and hence should help to improve conservation management of this endangered population of kangaroo rats.