Malta bound to have its fair share of jellyfish this summer

The French Riviera is gearing up for a summer of jellyfish and although the alarm bells have not yet started ringing here, Malta is bound to get its fair share of the pesky stinging sea creatures.

Reports in the British media said resorts in the north Mediterranean coast are being threatened by Pelagia noctiluca, known as the mauve stinger, for the eighth consecutive year.

Marine biologists have already spotted vast shoals of mauve stingers in the waters between Corsica and the French mainland and the town of Cannes is expected to set up booms and nets around its most popular beaches to protect bathers from jellyfish encounters.

Conservation biologist Adriana Vella said it is likely that the Maltese islands will see their fair share of jellyfish this summer, especially when sea currents and winds carry large offshore blooms towards local shores.

In the past, the menacing scyphozoans were only a problem every 10 years or so, making the last eight years an inconvenient phenomenon, which some have blamed on climate change.

Some ecologists have described the increase of jellyfish in the Mediterranean as a warning that something is wrong with the sea and Dr Vella pointed out that nature usually has ways of keeping natural populations under control.

In fact, when a population grows too much it does not find enough food and its predators' populations usually grow in number as well.

"But when for some reason the jellyfish food does not diminish and predators are already few, the large jellyfish blooms remain with us longer and become more persistent," she explained.

The Pelagia noctiluca, which can grow up to 10 centimetres in diameter, is very common in the Mediterranean, where it may appear in plague proportions, Dr Vella said, adding that this type of jellyfish is widely distributed in warm waters.

She added that the mauve stinger is one of the dominant jellyfish types that have been observed to bloom in very large numbers in the Mediterranean for a few years.

The jellyfish's sting is painful and can be dangerous to some people who are sensitive to them.

Asked about the cause of the jellyfish increase, Dr Vella said climate change could be a determining factor both directly and indirectly while over-fishing, marine degradation and biodiversity loss could also have an impact if it leads to the decrease in natural predators, like marine turtles. The latter are also ending up being victims to vessel propellers in local waters, with the Biological Conservation Research Foundation called to rescue a wounded turtle only last week.

Asked whether beaches could be protected from jellyfish, Dr Vella said a way of doing this would be by sending a special fleet of boats about 100 metres from the shoreline and collect incoming jellyfish in hand nets while making sure that other fish or marine organisms are not caught. She pointed out that jellyfish that are closer to the shore usually get beached and die.