Lessons from the International Coral Reef Symposium

The conference center in Bremen, Germany where the International Coral Reef Symposium was held.

In early July, I spent a week at the International Coral Reef Symposium in Bremen, Germany. Hundreds, if not thousands, of scientists traveled from all over the world to attend, and many more attended virtually.

It’s a big deal for coral reef scientists, and many people make every effort to attend and share what they’ve been working on. The topics range from coral restoration, to ocean acidification, to fish behavior, and more. Talks are organized into themed sessions, and topics that don’t fit within a session are placed into the general poster session one evening.

One of the day-long oral presentation sessions was dedicated to mesophotic reefs: the unexplored, unknown aspects of these unique ecosystems. It was unfortunately placed in the smallest room in the conference center.

Every single talk in this mesophotic session was standing room only, if you could even get in the door.

I believe this accurately represents the state of mesophotic reef science. It is often given minimal attention by the larger systems in marine science, but is gaining traction and interest by increasingly larger groups of scientists.

Dr. Tyler Smith of the University of the Virgin Islands presents on reefs in the US Virgin Islands. The map behind him shows how high-coral-cover sites in the Virgin Islands are concentrated mainly on the offshore mesophotic reefs.

The people who spoke during this session came from all over the world— California, Israel, the Indian Ocean, and of course, the Virgin Islands. The research topics were equally diverse. Each talk was unique, and most ended with the classic statement that “more research is needed”.

We learned that mesophotic coral cover is dropping, but not as steeply as it is in shallow areas, and can sometimes escape bleaching. We heard that corals transplanted from deep reefs to shallow ones can survive. We saw images of plastics snagged on deep coral, but also beautiful 3D reconstructions of small reef areas, as well as colorful newly described species of fish.

General agreement across all the talks was that mesophotic reefs are important ecosystems in their own right. They have unique fish and coral communities, and need to be targeted separately by research studies and management plans.

This gathering of marine scientists from all over the world, including some of the most prominent names in the field, still has a lot to learn from mesophotic reefs.

Reefs Unknown intends to help advance our collective knowledge.