Artificial reefs, a snare for bottom trawlers

The Balearic Mediterranean ( 25 June - 6 July 2005 )

Olimpia García

The new chapter of the Oceana Ranger in the Mediterranean has begun in the Balearic Islands. Majorca is the destination that welcomed our catamaran after its six-month transoceanic expedition, whose objetive now is to document the state of the Mediterranean and other European seas and the dangers they subjected to in order to protect them.

© OCEANA / Xavier Pastor

For the last couple of weeks, the Ranger has been a fact of life for the people of Majorca, who were able to get a close-up look at Oceana's catamaran, classified by the media of the islands as " The Defender of the Seas ". The Oceana Ranger crew, ranging from the captain and sailors to divers, biologist, researchers and underwater videographers, have been working on different projects to document the state of conservation of the Balearic Mediterranean.

The first job was undertaken in the marine reserves around the islands of Toro and Malgrats.

Oceana puts an emphasis on the value of this type of reserve, as it is the surest way of preventing the destruction of the sea beds and the ecosystems that live there. In a recent report presented to Jaume Matas, entitled " The Balearic Mediterranean: more clean, more alive ", Oceana believes that the balearic Islands should position themselves at the forefront of protected zones in the Mediterranean, developing a conservation plan whose objective is to declare 25% of the waters under Balearic jurisdiction as protected by the year 2010. The marine reserves should, amongst other aspects, observe the environmental importance of the area, its use as a zone for regeneration and migration, the representation of vulnerable, protected habitats and the existence of threatened species.

© OCEANA / Dana Harlow

The underwater cameramen and scientists of Oceana carried out diving sessions in the marine reserves of Toro and the Malgrats Islands, which were declared as protected areas in 2004, to document the state of their biological conservation. They filmed footage and took pictures to be studied and compared in the future so as to evaluate the evolution of the two reserves and study the growth of habitats.

In addition, Oceana documented the area between the two reserves of Toro and Malgrats, an inlet of snad where there is a plan to sink the Balears frigate to turn it into a wreck that can be visited by divers, while at the same time acting as an artificial reef. The aim of this exploration was to corroborate that the sinking of the wreck, if it happens, is in the right place, free of meadows of Posidonia oceanica or any other fragile habitat that might be negatively affected by the project. Shots of the current state of the area have been taken to compare them with future pictures of the mature reef, which will allow evolution towards greater biological wealth. The positioning of this wreck as an artificial reef will generate greater biodiversity, forming another reef ecosystem which will not damage the sandy bottom and will allow the growth of native Mediterranean species. Oceana has insisted that if the project goes ahead, the Calvià Town Council, the instigator of this project, should complement it with the extension of the reserve area by joining up the two marine reserves of Toro and Malgrats to form a single area - approximately five times the size of the two existing reserves - and thus guarantee grater protection in this part of the Balearic Sea.

The second of the Oceana Ranger's objectives in Balearic waters was geared towards installing artificial reefs against bottom trawling in the Santanyi area. Here, as in other parts of the Mediterranean, trawlers are fishing at unauthorised depths ( below 50 metres ) and damaging meadows of Posidonia oceanica, regarded as one of the principal ecosystems in the Mediterranean. For this project, Oceana is supporting the installation of artificial anti-trawl reefs which act as a " snare " for trawl nets, which become entangled, and stops them from fishing in areas prohibited by law. With the help of maps created by lateral-sweep sonar commissioned by the Balearic government, the Oceana ranger headed for specific points with demonstrable evidence of trawling at depths of below 34 metres.

© OCEANA / Mar Mas

The Oceana divers carried out dives at these points, the first at a depth of 30 metres at half a mile from the coast and a second one during which it was proven that the trawlers had even fished ar depths of 20 metres under half a mile from ths coast. The pictures taken by underwater film producer, Mar Mas, and the Oceana photographers provide documented evidence of areas of de devastated Posidonia oceanica, together with others in an excellent state of health, depending on whether - or not - natural obstacles had hindered the actions of the trawlers. Once the Ranger had anchored for the night, these images were studied by the Oceana scientists in order to plan more dives. The next day, the Oceana team dived to 20 and 30 metres at the points where the Balearic Government plans to install a field of artificial anti-trawl reefs formed by three lines of barriers and some 200 modules. Once again, the marks that this kind of trawling leaves behind were recorded, which not only causes serious damage to the sea beds but also results in the incalculable loss of species.

 

A DOCUMENTARY ABOUT ILLEGAL DRIFTNETS

Oceana in the documentary made by the producer EarthOcean about illegal drifnetters in the Mediterranean Sea. The video includes an interview with Xavier Pastor, Oceana’s Director for Europe, and also images of illegal driftnetters recorded during the expeditions on board the catamaran Oceana Ranger. Driftnets are banned since 2002 because they represent a major threat for the conservation of endangered species such as marine turtles and cetaceans.

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