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Review of jellyfish blooms in the Mediterranean and Black Sea

Year of publication 2013

Place of publication Rome, Italy ;

Pages 63 p.

Author Boero, F.

Publisher FAO ;

Product type Book (series)

ISBN 978-92-5-107457-2

Series title Studies and reviews (General Fisheries Commission for the Mediterranean)

Series number No. 92

Edition 1

Synopsis (short abstract) Gelatinous plankton is formed by representatives of Cnidaria (true jellyfish), Ctenophora (comb jellies) and Tunicata (salps). The life cycles of gelatinous plankters are conducive to bloom events, with huge populations that are occasionally built up whenever conditions are favorable. Such events have been known since ancient times and are part of the normal functioning of the oceans. In the last decade, however, the media are reporting on an increasingly high number of gelatinous plan kton blooms. The reasons for these reports is that thousands of tourists are stung, fisheries are harmed or even impaired by jellyfish that eat fish eggs and larvae, coastal plants are stopped by gelatinous masses. The scientific literature seldom reports on these events, so time is ripe to cope with this mismatch between what is happening and what is being studied. Fisheries scientists seldom considered gelatinous plankton both in their field-work and in their computer-generated model s, aimed at managing fish populations. Jellyfish are an important cause of fish mortality since they are predators of fish eggs and larvae, furthermore they compete with fish larvae and juveniles by feeding on their crustacean food. The Black Sea case of the impact of the ctenophore Mnemiopsis leydi on the fish populations, and then on the fisheries, showed that gelatinous plankton is an important variable in fisheries science and that it cannot be overlooked. The aim of this report is to review current knowledge on gelatinous plankton in the Mediterranean and Black Sea, so as to provide a framework to include this important component of marine ecosystems in fisheries science and in the management of other human activities such as tourism and coastal development. Fact sheets on the most important gelatinous plankters of the Mediterranean and Black Seas are included as an appendix.

Statutory body / Meeting title General Fisheries Commission for the Mediterranean (GFCM)

Language English

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