HELMUTH, Brian; STRICKLAND, Denise; Univ. South Carolina, Columbia; Univ. South Carolina, Columbia: Risky Business in the rocky intertidal: don’t get caught with your tide down

Rocky intertidal invertebrates and algae are aquatic organisms that must contend with the rigors of the terrestrial environment during low tide. As such, they have emerged as potential bellwethers for the effects of climate change on natural ecosystems. Recent evidence has shown that spatial and temporal patterns in body temperature during low tide are highly complex and often counterintuitive because of the effects of organism shape, size and behavior on heat flux. We present a method of �risk analysis� based on 4 years of mussel (Mytilus californianus) body temperature data collected in Monterey, CA. Our method accounts for the effects of terrestrial climate, tidal regime, intertidal elevation and wave splash in determining the probability of exposure to temperature extremes during low tide. By separating the role that each of these factors play, we can quantitatively examine the effects that changes in any one of these parameters is likely to have on organism temperatures. We can also characterize sites in terms of the likelihood that mussels will experience a given body temperature, and identify times of year when these potentially stressful events are most likely to occur.