Collaborative Studies of Post‐eruption Colonization Dynamics on EPR Vents



A recent seafloor eruption on the East Pacific Rise eliminated the fauna of hydrothermal vents near 9°50’N, providing a natural clearance experiment and an opportunity to study the effects of larval supply on recolonization. We were able to explore this question because we had been monitoring larval supply and colonization at the site prior to the eruption, and were able to mobilize quickly afterward to resume sampling.  We found a striking change in species composition of pioneer colonists after the eruption, driven in part by larval supply. These observations raise a fascinating question: will these new pioneer species persist and lead to a stable alternative community, or are they simply the early stage in a succession that will transition back to the pre‐eruption fauna? We propose to answer this question by establishing long‐term monitoring of community composition at the eruption site. An invitation to participate in a French cruise to the EPR has given us an opportunity to start this effort in collaboration with a colleague who will provide associated measurements of biologically important environmental conditions (pH and sulfide). In combination, these biological and chemical measurements will allow us to evaluate the roles of initial larval supply and subsequent environmental change in the recovery of EPR vent communities.