Vulnerable basking sharks disappearing from the Med
Simona Clò and Eleonora de Sabata of Shark Alliance members CTS and MedSharks respectively, presented the findings of their joint research into twenty rare basking sharks that appeared off the coast of Sardinia last winter, at Italian dive show Big Blu.
The basking sharks' presence was recorded by 'Operation Basking Shark', which also collected DNA samples and tagged one shark - the first ever to be tagged in the Mediterranean sea. This winter, no sharks were observed in the area.
Clò and de Sabata, spoke to an attentive audience of journalists, divers, yachtsmen, anglers and shark lovers during the Big Blu Show, a dive and yachting show which took place in Rome from 8-12 March, attracting a crowd of over 100.000 people.
The basking shark is the largest fish in the Mediterranean Sea and can grow up to 10 meters in length, but feeds off the tiniest organisms - plankton. Basking sharks can live for over 50 years and only start reproducing at 16-20. Each animal has a slightly different dorsal fin and tail. Through these tiny differences each shark can be identified.
Basking sharks arrive along the Italian coast at the end of winter in a totally unpredictable way, and then disappear. A migratory fish, scientists have no idea where they go on leaving Mediterranean waters.
The sharks researched by Clò and de Sabata swimming off the Sardinian coast are among the few that still survive in the Mediterranean Sea.
The 2007 IUCN Red List of Endangered species, which will be published in April, lists basking sharks as "vulnerable".
Although they have declined by 50-70%, basking sharks are not the species most at risk in the area: sandbars, great whites and spiny dogfish have declined by 70-90%, while portbeagles, makos, sand tigers and angel sharks are faring even worse having declined by 90% and are considered "critically endangered".
These figures stunned the dive show audience, which burst into spontaneous applause as an equally shocked Donatella Bianchi (a well-known Italian TV star) promised to support Domitilla Senni of the Shark Alliance in the battle to push for a conservation plan for sharks in Italy.