During our 2015 exploration in the Gulf of Mexico, the team encountered a spectacular brine pool and collected mussel samples from the area. A brine lake is water far more saline than the surrounding seawater so it doesn't mix and creates its own surface tension. As a result, you see surface waves and find very unusual geologic features and biology living on their "shores."
On this leg of the expedition, we will return to cold methane seeps and brine pools investigated during the 2014 season to continue an examination of the symbiosis between the mussels that live at the seeps and the bacterial symbionts that they host. Previous work has shown that different species of Bathymodiolus mussels have different combinations of symbionts that allow them to survive under varied conditions at the seeps. The symbionts utilize hydrogen sulfide or methane. Sulfide-oxidizing symbionts use the energy from sulfide to grow using CO2 as their sole carbon source.