Record sea temperatures seen in the Mediterranean could devastate marine life


A mass mortality event is a single, catastrophic incident that quickly wipes out a large number of species. About 88% of these events in the Mediterranean were associated with hard seabed inhabitants, such as corals. However, seagrass beds and the more diverse soft seabed community were also severely impacted, accounting for 10% and 2% of these events, respectively.

Death in shallow water

More than two-thirds of the deaths of marine organisms occurring on the hard seabed occurred in the shallowest waters. Marine environments between 0 and 25 meters deep are subject to particularly intense warming and are home to some of the most biodiverse ecosystems in the Mediterranean, made up of coral-like organisms. Other research estimates that marine heat waves are responsible for the loss of 80-90% of Mediterranean coral density since 2003.

Founder species tend to be habitat-forming organisms and are therefore essential in structuring an ecosystem. They serve as a nursery, provide protection from predators and serve as a food source. Founder species are essential for maintaining biodiversity and their loss will have repercussions on other species. As basic speciesthe loss of corals, seagrass and algae is of particular concern.

It is not just intense heat stress that causes mortality episodes. High water temperatures are associated with the proliferation of pathogenic organisms, such as bacteria, fungi and viruses. This can further reduce the ability of the ecosystem to adapt to extreme heatcontributing to further ecological damage.

Migration of marine life

In addition to causing widespread death of marine life, marine heat waves often trigger migrations. Warm-water invasive species will move to warmer areas, replacing species that escape rising temperatures. Anecdotal evidence suggests that the exceptional temperatures seen across the Mediterranean this summer could lead to significant mass migration.


Comments are closed.