New Coral Reef Discovered Along Italian Adriatic Coast
Scientists have recently discovered a new coral reef near the city of Monopoli, in the region of Puglia, on the Adriatic coast of south-east Italy – the first known coral reef found in Italian waters in modern times.
While the Mediterranean Sea and its Adriatic adjunct are not devoid of coral, much of it is comprised of species of soft coral, not the stony reef-building structures that are familiar in tropical waters. The Mediterranean was once home to a vast expanse of coral reefs, with fossil evidence dating back to the late Pliocene (3 - 2.6 Ma), when global temperatures would have been 2-3°C warmer than today.
Distribution of coral reefs in the present day Mediterranean is scarce, with the largest aggregations of known reef-building coral found in the Columbretes Islands Marine Reserve off the coast of Spain, and the Mljet National Park of Croatia, which borders the eastern coast of the Adriatic Sea.
In a paper published in the online journal Nature, lead researcher Giuseppe Corriero from the University of Bari Aldo Moro, details how the 2.5km section of recently discovered reef, is even more remarkable in that it is a mesophotic reef - formed from coral species that are able to thrive in mid-low light levels. Such corals are usually found at depths of between 30-40m, and can extend to the limits of the photic zone (the maximum depth to which light penetrates the water), which can be as deep as 200m in some locations. The Puglia reef was discovered between 30-55m of depth, and may extend much further along the Italian coast.
Most species of hard coral (scleractinians) encountered on tropical reefs are symbionts with a single-celled dinoflagellate (also referred to as a form of algae) known as zooxanthellae. According to the report, the main reef-building scleractinians of the newly discovered reef 'lacked algal symbionts', and therefore the production of the underlying calcium carbonate 'skeleton' of the reef is a result of the corals feeding on a large amount of available suspended organic matter in the area. The lack of zooxanthellae also means the reef is much less colourful than those found in tropical waters.
In an interview with local journal Bari Today (in Italian, click here for an English translation) Puglia's regional councillor for the environment, Giovanni Stea, plans to grant the reef status as a marine protected area (MPA). 'First of all because it could extend well beyond that stretch of sea, constituting a unique case in the Mediterranean,' said Mr Stea. 'But also because the area undoubtedly represents the ideal habitat for many species and marine organisms, so now, once the discovery is made, it becomes necessary to preserve it with the collaboration not only of the Institutions but also of the citizens and the categories of sea workers'
'In the early 1990s I worked as a marine biologist in the Maldives,' said Mr Corriero. 'But I never thought I'd find a coral reef, 30 years later, a stone's throw from my house.'
The full report, published by Prof Giuseppe Corriero et al can be found at www.nature.com/articles/s41598-019-40284-4