SymbioSwap

Testing symbiotic algal exchange for Mediterranean corals more resistant to climate change

The SymbioSwap project

CONTEXT AND MAIN ISSUES

The Mediterranean Sea is a global biodiversity hotspot, hosting around 10% of marine biodiversity within just 1% of the ocean’s surface area. Remarkably, one in five species found here is endemic to the region.

However, the Mediterranean is also a climate change hotspot, warming 20% faster than the global average. In addition to this warming, the region is increasingly affected by frequent and intense marine heatwaves, which are often fatal to sessile fauna and surface invertebrates (though less so for fish, which can escape to deeper, cooler waters).

Simultaneously, the Mediterranean is becoming a refuge for tropical species migrating from the Red Sea and Indian Ocean via the Suez Canal, in search of more favorable conditions.

GOALS

Transplant symbiotic algae between Mediterranean and tropical corals to study their role in enhancing coral resistance to rising temperatures and preventing bleaching.

METHOD

The study focuses on the symbiotic relationship between corals and their algae, essential to their survival and often disturbed by bleaching. Using a model system approach, we will equip cold and warm water sea anemones with algal symbionts from opposite thermal regimes to test the role of these new symbioses in coral acclimatization and their resistance to global change.

The experiment aims to decipher one of the key mechanisms through which corals adapt to climate change.

HOW IS THIS PROJECT INNOVATIVE?

The project’s originality lies in its exploration of new symbiotic interactions between corals and algae to enhance thermal tolerance. This approach is unprecedented in the Mediterranean and could pave the way for assisted acclimatization strategies in the face of global warming—a promising avenue for the conservation of temperate reefs.