Climate change: a growing threat to oysters

The study conducted by these French scientists and recently published in Environmental Research Letters shows that mild, wet winters dominated by atmospheric circulation patterns of the positive phase of the North Atlantic Oscillation (NAO+) generate environmental conditions leading to high adult oyster mortality throughout the following year. In winters dominated by the NAO+ regime, the increase in temperature favours pathogens, and a simultaneous increase in freshwater inflows from rivers after heavy rains weakens oyster populations.

"Marine resources are essential for humankind’s food supply. Among these resources, shellfish are of paramount social, economic and cultural importance," says Yoann Thomas, a former post-doctoral student at the Mer Molécules Santé (MMS) laboratory who is now a researcher at the Institut de recherche pour le développement (IRD). "[Oyster] production is vulnerable to anthropogenic pressures and global warming. There is an urgent need to reduce our energy consumption and greenhouse gas emissions to avoid further disruption of coastal ecosystems."