When walking along the sandy beaches of Paros we often stumble across tangled masses of what appears to be “seaweed” or sea-grass. In some areas, the beached, bleached and piled, sea-grass forms thick soft mattresses of ash-brown colour - great fun for kids to jump on. Walking along the coast on a calm day we are able to see clearly patches of living Posidonia oceanica (or Neptune grass) in the shallows. Also, when flying low as the plane takes off or comes into land, the patches of seabed darker than the rest are just that - sea meadows of Neptune grass, Posidonia oceanica.
Posidonia is a most important sea-habitat, protected by the EU directive 92/43 (Nature 2000) code 1120-priority habitat. During the past 30 years, numerous scientific studies have shown the great importance of the role it plays within the marine coastal environment of the Mediterranean Sea. Posidonia is not a ‘sea-weed’ or algae, it is a real phanerogam which means it reproduces sexually (mates openly and unashamedly!). It has the basic structure of a plant, like flowers (found on the beach as sea olives), a root system, rhizomes and leaves. It needs clear and clean water in which to live, it photosynthesizes, and produces about 15-20 litres of O2 every 24 hours! No wonder it feels so good to walk on the beach nearby!
The Posidonia meadows provide habitation for more than 400 plants and 1000 animals making it the most important marine habitat in the Mediterranean. Its very presence guarantees a healthy and clean marine environment.
The meadows are critical to ensure the stability of sandy shores and sea-beds as they prevent land erosion. Waves and currents are dampened by the Posidonia matte and suspended sediment is trapped and accumulates within the elaborate rhizome structure, forming submerged breakwaters that dissipate wave-energy.
An example of this in Paros is the coastal erosion in progress on the northern beaches of Paroikia after the destruction of the rock outcrop and the surrounding Posidonia meadows in the centre of the bay a few months ago. The meadows may also be destroyed by pollution, yacht-anchors and fishing gear such as that used in sea-bed trawling.
So, it’s really worth a slow snorkel above these meadows to watch the ‘show’: Fish hunt and are hunted, octopus patrol for food, lobsters (without ‘spines’) and sea urchins crawl and feed and cuttlefish hover and hide in the blades of grass. Sea-horses are also to be spotted there as well as whelks, tubeworms, pipefish, shrimps, starfish, brittle-stars and sea-cucumbers!
One of the activities of the Aegean Diving College, Paros is the monitoring of the Posidonia meadows around the island. We visit several sites every year in every season and monitor Posidonia regression or expansion near marine construction areas, sewage outfalls, intensive fishing grounds or favourite yacht anchorages.
Those who dive with us, students, visitors or tourists, take an active part in these monitoring experiments and soon acquire a good understanding of the underlying ecological principles involved.
The Aegean Diving College operates from the Poseidon Apartments in Chryssi Akti (Golden Beach) and will be active in discouraging anchor-dropping over the Posidonia meadows by creating a EU-funded mooring-buoy system around the island.
The initiative - Marine Protected Areas in the Aegean Sea - started in December 1999 by organising a two day conference in “Archilochos” with a goal to establish a network of marine protected areas in the Aegean Sea, starting with a pilot programme around Paros this year.
ADC has begun teaching marine environmental education in primary schools of the Aegean islands, following a programme prepared with the Greek Ministry of Education named “Young Nautilus” (O Mikros Navtilos = young mariner).
For more information check our website - www.aegeandiving.otenet.gr. or email: email@example.com.
Look out for my next article to find out how to remove sea-urchin spines from your skin and how to enjoy the “offensive little critters” with suma or ouzo! Also find our how spearfishing results in sea-urchin population- explosions making shallow swimming a tricky exercise.