Chapter

Jellyfish Blooms

pp 237-266

Date:

Pelagia noctiluca in the Mediterranean Sea

  • Antonio CanepaAffiliated withInstitut de Ciencies del Mar, Consejo Superior de Investigaciones Científicas, ICM-CSIC Email author 
  • , Verónica FuentesAffiliated withInstitut de Ciencies del Mar, Consejo Superior de Investigaciones Científicas, ICM-CSIC
  • , Ana SabatésAffiliated withInstitut de Ciencies del Mar, Consejo Superior de Investigaciones Científicas, ICM-CSIC
  • , Stefano PirainoAffiliated withUniversità del Salento, CoNISMa
  • , Ferdinando BoeroAffiliated withUniversità del Salento, CoNISMa, CNR-ISMAR
  • , Josep-María GiliAffiliated withInstitut de Ciencies del Mar, Consejo Superior de Investigaciones Científicas, ICM-CSIC

* Final gross prices may vary according to local VAT.

Get Access

Abstract

Over recent decades, man’s expanding influence on the oceans has begun to cause change in some regions, including in the Mediterranean Sea. New proliferations of jellyfish may be occurring in the Mediterranean Sea, possibly in response to the cumulative effects of some of these anthropogenic impacts. In the Mediterranean Sea, many of these “proliferation events” are due to Pelagia noctiluca, an oceanic scyphozoan that has become very abundant along the coasts. Pelagia noctiluca is usually considered to be the most important jellyfish species in the Mediterranean Sea due to its widespread distribution, abundance, and ecological role and also because of its negative interaction with humans. Climatic conditions that favor enhanced reproduction by P. noctiluca and probably also determine optimal conditions for the formation of blooms are characterized by mild winters, low rainfall, high temperature, and high-atmospheric pressure. The Medusa Project in Catalonia aims to understand the spatiotemporal dynamics of the jellyfish populations in the NW Mediterranean Sea by undertaking daily sampling during summer (May to September) of 243 beaches, covering more than 500 km of coast. Data on beach strandings along the Spanish Catalan coast revealed that jellyfish occur in greatest concentrations along the northern Catalan coast and on beaches located close to marine canyons. The arrival of P. noctiluca to the coast depends firstly on the offshore production of jellyfish. Oceanographic structures like fronts, which enhance and maintain high levels of biological production and provide ideal conditions for feeding, growth, and reproduction of the jellyfish are present in the NW Mediterranean. The weakening of the front results in large numbers of P. noctiluca being driven into the coast by southeast winds. In the NW Mediterranean Sea P. noctiluca exert top-down control over a variety of prey including fish eggs and possibly the invasive ctenophore Mnemiopsis leidyi. P. noctiluca is also responsible for the majority of the stings incurred by bathers along the Catalan coast. Finally, we recommend that similar sampling programs should be done elsewhere to better understand changes in the distribution, abundance, and blooming patterns of dangerous jellyfish species.

Keywords

Jellyfish blooms Pelagia noctiluca NW Mediterranean Sea Catalan coast Tourism Long-term monitoring Oceanography Climate variability Physicochemical variables Socioeconomic impacts Jellyfish-fish interactions