Meeting Abstract
Mussels (Mytilus californianus) are major inhabitants of intertidal zones along the California coast and serve as indicators for the effects of climate change in marine systems. We are interested in studying how environmental stressors, such as increased temperature and shifts in food availability, affect mussel physiology across multiple biological levels. Thermal tolerance in M. californianus may be tied to food availability, although the mechanism that underlies this link is not well understood. We acclimated mussels to different combinations of feeding regimes (1.5% and 0.25% mussel dry weight·day-1) and daily maximum temperature during emersion (20 and 30°C) to look at the effects of acclimation on the ability of the mussels to respond to acute heat stress (33°C). We sampled mussels at the beginning and end of each high tide cycle for 48 h before and after heat shock. Because the gill tissue is responsible for transporting food from the environment, we used particle velocity, the rate at which particles pass along the gill, as a proxy for the mussels’ response to temperature stress. Using high definition video, we tracked the movement of fluorescent beads along the surface of an excised piece of gill tissue from individuals in each treatment (n = 4). Videos will be analyzed using Particle Image Velocimetry (PIV) software to look at the effects of food availability and thermal history on the ability of mussels to recover from acute heat stress. We predict that mussels acclimated to low food availability will recover more slowly from heat shock, manifested in slower particle velocities, compared to the high food groups, resulting from depleted energy stores (funded by NSF IOS-1557500).
