Meeting Abstract

8.3  Sunday, Jan. 4  Long-term reconstructions of limpet body temperatures allow estimation of the frequency and severity of stress events, and reveal potential consequences for small scale distributions on a rocky shore MILLER, L.P.*; DENNY, M.W.; HARLEY, C.D.G; Hopkins Marine Station, Stanford University; Hopkins Marine Station, Stanford University; University of British Columbia millerlp@gmail.com

The distribution of species within microhabitats at a site may be driven by a variety of factors, both biotic and abiotic. To examine the potential role of high temperature and desiccation stress on the small-scale distribution of the limpet Lottia gigantea, we used a combination of physiological assays and biomechanical modeling techniques to hindcast the occurrence of sub-lethal and lethal stress events in a population. Sub-lethal and lethal stress exposures were conducted using an environmental chamber designed to recreate stressful field conditions in the laboratory. Heat-shock protein 70 expression was used as a metric of sub-lethal stress, and median lethal temperatures were calculated. These physiological parameters were combined with the output of a bio-physical heat-budget model to predict conditions under which L. gigantea would experience significant sub-lethal stress or mortality. Within a subset of the microhabitats at our site, we predict that the vertical distribution of limpets could be set by rare high temperature and desiccation events. The synthesis of these techniques has the potential to help inform ecologists about the role of physical and physiological constraints in shaping communities and their responses to future environmental changes.