The onshore team focuses on community dynamics on rocky intertidal shores at scales ranging from single sites to the entire US west coast. Observations, measurements and experiments are carried out to understand the relation between inputs of nutrients, propagules and particulates (detritus, phytoplankton), life histories, and species interactions in determining community structure. To quantify recruitment, we install collectors on the shore at up to 10 sites. We are sampling recruitment of algae, barnacles, crabs, echinoderms and mussels. To test interactions between predators and prey, and herbivores and algae, we establish field experiments. A current focus is on geographic variation in the interaction between the mussel Mytilus californianus and the sea star Pisaster ochraceus. Effects of nutrients on the growth of animals and plants, the effects of upwelling and relaxation periods on communities, and how communities change over time are other current projects.