Natural disturbances play a fundamental role in the structuring of ecosystems by altering resources, substrate availability, or the physical environment. Because the effects of disturbance are typically heterogeneous and patchy, non equilibrium states prevail in most ecosystems. The rocky intertidal zone has proven to be an excellent model system for the exploration of how disturbance and patch dynamics influence non equilibrium ecosystems. This is in part due to the fact that disturbance in the rocky intertidal is typically dominated by a single physical factor, the hydrodynamic forces generated by breaking waves. Recently, a biomechanical approach has been developed that predicts physical disturbance on rocky shores as a function of time and the `waviness` of the sea offshore. Preliminary tests of this mechanistic approach are promising, suggesting that such an approach can be a valuable tool for understanding the ecological consequences of seasonal and year to year variability in wave exposure. A critical parameter in the biomechanical approach is the strength of an organism relative to the hydrodynamic forces it encounters. There are numerous studies indicating that the ability of an organism to withstand wave action is modified in response to the flow environment. Such modifications must be taken into account in order to accurately predict rates of disturbance in changing environments. This study will provide a detailed understanding of the mechanics which allows this species to dominate wave swept shores, and will enhance our ability to predict the rate of disturbance of this ecologically important species. Furthermore, this study allows for the prediction of the quantitative response of mussels to any future shifts in wave climate. Given current evidence that increases in wave exposure may be common in the near future, these estimations are likely to form a valuable test of our ability to predict the ecological consequences of climate change.
