Acquiring a ‘base datum of normality’ for a marine ecosystem: the Ross Sea, Antarctica

The Ross Sea Shelf Ecosystem (RSShelfE) offers the last chance to understand ecological processes in a system where both top-down and bottom-up forcing are still intact. Elsewhere in Earth’s oceans the systems used for understanding ecological processes and fishery effects all have lacked significant, natural top-down forcing for such a long time that it is a concept rarely considered by researchers who currently investigate open-ocean systems. Herein, the importance of top-down forcing in pelagic and neritic marine ecosystems is reviewed with concrete evidence given for its existence in the current functioning of the RSShelfE. In spite of this unique evidence for the Antarctic region, much remains to be learned about cross-component interactions in the Ross Sea system. Should the RSShelfE be un-naturally altered, an easy accomplishment given increasing fishery pressure, we will have lost the last opportunity to understand the processes that take place in a healthy, complete marine ecosystem.