Ribbed mussels are a key species, increasing salt marsh resilience along the Atlantic coast of North America. Like other marine bivalves, they have planktonic larvae, facilitating broad dispersal. Across their geographic distribution, larvae can experience a wide range of ocean temperatures and food abundance. Climate change is likely to alter local temperature and food availability, which may impact larval survival, growth, and development. Understanding the consequences of climate change driven temperature and food availability will be especially important as they can impact mussel distributions and population dynamics. But, we do not presently understand how these factors impact early life stages. Therefore, we tested the combined effects of temperature and food quantity on survival, growth, and time to metamorphosis in larval ribbed mussels.
We found highest survival at 20°C, but larvae were slow to metamorphose, and lowest survival (no metamorphosis) at 15°C. In general, higher food availability improved survivorship at most temperatures. Larvae developed fastest at 30°C and food availability did not affect development time. Food availability increased larval growth except at the coldest temperature and larvae were larger with increasing temperature. These data suggest tradeoffs between survivorship, growth, and development at different temperatures and will be used to parameterize systems models to understand the impacts of combined factors (including temperature and food availability) during the larval stage on ribbed mussel populations in salt marshes.