My research interests center on river food webs. I have studied interactions among fish, birds, amphibians invertebrates, and algae in temperate and tropical rivers. I am particularly interested in how attributes of species affect food web structure and dynamics, and how food web interactions change with environmental context. We have studied, for example, the interplay of trophic dynamics with hydrologic and productivity regimes in northern California rivers, as well as impacts of invading alien species. Much of our current field work takes place in the Eel River, based out of the Angelo Coast Range Reserve in Mendocino, CA. The Angelo Reserve, managed by UC Berkeley, is one of the University of California Natural Reserve System's 40 research and teaching reserves. Angelo currently hosts collaborative teams of researchers studying the interaction of landscapes and ecosystems over long and short time scales. Currently, Earth scientists and ecologists are studying how climate, topography, vegetation cover and lithology affect water cycling and storage; including storages and slow release of water that can maintain streamflow during drought. My students and I link to their efforts in order to forecast landscape settings and climate conditions that may flip river food webs from ones based on primary production by edible diatoms that support salmonids and their invertebrate prey, to webs dominated by potentially toxic cyanobacteria, which may be becoming more prevalent under extreme low flow. We are also investigating how the fluxes of organisms and materials that link tributaries, mainstems, uplands, and the coastal ocean will respond to changes in biota, land cover, or climate across river networks.
In the News
The debate over the legalization of marijuana has focused primarily on questions of law, policy and health. But a new paper co-authored by UC Berkeley researchers shines a spotlight on the environmental damage caused by illegal marijuana plantations in sensitive watersheds.
University of California, Berkeley, scientists will receive $4,900,000 over the next five years to study the nearly 10,000 square kilometer Eel River watershed in Northern California and how its vegetation, geology and topography affect water flow all the way to the Pacific Ocean.
Four University of California, Berkeley, faculty members – physicists John Clarke and Bernard Sadoulet, chemist John Hartwig and ecologist Mary Power – have been elected members or foreign associates of the National Academy of Sciences, bringing UC Berkeley’s total NAS membership to 141.
A new UC Berkeley study cautions, however, that restored wetlands may not recover to the condition of a natural, undamaged wetland for hundreds of years, if ever.
A new paper reviewing the impact of the loss of large predators and herbivores high in the food chain confirms that their decline has had cascading effects in marine, terrestrial and freshwater ecosystems throughout the world. The study, co-authored by UC Berkeley researchers, highlights the impact “apex consumers” have on the dynamics of fire, disease, vegetation growth, and soil and water quality.