leaves of plants that are very fibrous and that contain high quantities of tannins and other polyphenolics, such as oak trees. This unusual specialization allows them to capitalize on food sources that are both abundant and that lack major competition. Big-eared woodrats consume oak leaves as greater than 85% of their diet, and this specialization differentiates big-eared woodrats from other species in the Neotoma genus that prefer more mixed diets of a variety of plant species. Behavior and ecology Diseases A study of the species found the "Bear Canyon" virus, a mammarenavirus, traditionally associated with the California mouse, is actually passed by the big-eared woodrat before host-jumping to the California mouse. Conservation status The big-eared woodrat is listed as a least-concern species by the International Union for Conservation of Nature, but there are growing conservation concerns due to habitat loss and fragmentation, which in Southern California is particularly caused by urbanization. This is a concern not only due to the potential for future declines in woodrat populations, but also due to the role these animals hold as an important prey species in the diets of predatory birds. References Neotoma Mammals described in 1893 Taxa named by Oldfield Thomas