Giovanni Sanna

Cold-water coral sensitivity

Cold-water corals (CWCs) are a heterogeneous group of cnidarians found in cold and deep waters across the world’s oceans. They include calcifying species that form astonishing deep-sea reef structures, providing habitat for thousands of other species. These reef-building CWCs are thought to produce a remarkable variety of intraspecific skeletal forms in different environmental settings. However, unlike their tropical shallow-water relatives (much easier to access), their phenotypic variation has never been thoroughly examined, despite its biological, ecological and geological significance.

The primary aim of this project is to determine how growth, morphology and reef-forming potential of CWCs vary in response to oceanographic conditions. The focus is on Lophelia pertusa ( Desmophyllum pertusum), the most widespread CWC as well as an important ecosystem engineer, particularly in the Atlantic Ocean. Using morphometric and image analysis techniques on a large Atlantic sample, Lophelia’s intraspecific skeletal variation is analysed quantitatively and qualitatively across a broad geographical range, in relation to environmental factors at various scales. This will ideally provide insights into the current viability of CWC reefs and their sensitivity to marine ecosystem changes, and possibly improve our understanding of coral phenotypic plasticity.