Introduction I have pursued a wide range of research projects in ecology and conservation biology using plant, insect, pathogen and mammalian systems.  This work has a strong emphasis on field experiments and addresses the roles played by species in shaping populations and communities.  Much of my research has focused on the influence of native and non-native mammals on plant communities in northern California.  For example, I am interested in how plant communities respond to the soil disturbances created by feral pigs, which are so prominent throughout the world.  In addition, I have numerous long-term experiments underway that address the impacts of black-tailed deer, hares and various small mammals on dune communities and oak woodlands.  I am increasingly interested in biological invasions and the effects of non-native species on the communities they invade.  Since 2000, I have been collaborating with numerous colleagues on a large-scale project that seeks to understand the biotic and abiotic factors that drive the spread of Phytophthora ramorum, an exotic pathogen that causes Sudden Oak Death throughout much of northern California and southern Oregon.  Currently, I am conducting field experiments that address the effects of cattle grazing in coastal grasslands on an endangered lycaenid butterfly, its host plant and the surrounding plant community.  My collaborators and I are especially interested in whether cattle grazing can be used as an effective tool for reducing the dominance of exotic plants while at the same time promoting the success of native taxa.  I have an active group of graduate students working with me on research projects in ecology, conservation biology and restoration ecology – and am always on the look-out for bright, motivated individuals who want to join our group.