First evidence of the presence of plastic litter in jellyfish (Press review)

The study, published in Nature Scientific Reports, is the result of observations in the surroundings of Ponza Island. According to the Italian-Russian research team, jellyfish may be an important vector of plastic and other litter along the marine trophic web, up to the large vertebrates.

A study recently published in Nature Scientific Reports  - “Episodic records of jellyfish ingestion of plastic items reveal a novel pathway for trophic transference of marine litter” – provides the first evidence of the presence of marine litter in Pelagia noctiluca, a jellyfish species commonly found throughout the Mediterranean Sea. 

Figure 1. Field observation of a Pelagia noctiluca specimen, with a plastic fragment trapped between the oral lobes. The plastic comes from the packaging of a famous cigarette brand.

This study, coordinated by Armando Macali (University of Tuscia), Elisa Bergami (University of Siena), in collaboration with Alexander Semenov from the Lomonosov State University of Moscow and with a contribution by Ilaria Corsi (University of Siena), has revealed in particular that jellyfish is an “unexpected” target to plastic at sea. The research has been carried out on P. noctiluca specimens collected in the sea waters surrounding Ponza Island, characterised by plastic vortex, i.e. areas of marine litter accumulation, formed by the convergence ofsuperficial currents. This observation dates back to September 2016, within the framework of the Aquatilis expedition conducted by an international team of researchers for the purpose of describing Mediterranean marine biodiversity. During the underwater activities, researchers observed several jellyfish interacting with the marine litter in suspension (Figure 1).

The collection and analysis of a number of specimens of P. noctiluca confirmed the presence of synthetic debris inside their gastrovascular cavities (Figure 2). This evidence has led to the assumption that jellyfish can ingest marine plastic litter, probably recognising it as prey because of the chemical-physical properties inherent in plastics.
Valentina Venuti and Vincenza Crupi from the University of Messina as well as Francesco D’Amico and Barbara Rossi from Elettra Sincrotrone Trieste of Area Science Park carried out the characterisation of the plastic debris found in the jellyfish by ATR-FTIR spectroscopy and UV-Raman spectroscopy respectively. Both techniques univocally identified two plastic fragments (>1 cm) made of high-density polyethylene and flame-retardant polyethylene, in addition to a third zinc-rich paint fragment.

Figure 2. A 1.7-cm-long polyethylene fragment, extracted from a jellyfish umbrella.


For the analysis of the plastic fragments, the power and versatility of UV Raman spectroscopy with synchrotron light performed on the IUVS light beam (Inelastic Ultraviolect scattering) has been fundamental. Thanks to this technology, the precise identification of the chemical composition of the materials found in jellyfish has been possible.
 
The accumulation of marine litter, plastic items in particular, in the seas and ocean of the entire world has been documented since the ‘70s and has recently been identified as one of the most severe forms of pollution at global level. Larger plastic fragments at sea, known as macroplastics (> 1 cm), can pose a hazard to many marine animals, which get weaker and die from plastic ingestion or entanglement (for instance, in derelict fishing gear), choking, drowning as well as dysfunctional feeding. The presence of plastic is putting at risk many organism species but, to date, most studies have focused on fish, turtles and marine birds. For instance, turtles are believed to mistake plastic bags suspended in the water column for jellyfish and to ingest coloured synthetic debris confusing it for prey.
 
These cnidarians make up a considerable part of the diet of large vertebrates, such as turtles and fish, including species of commercial significance, such as tuna and swordfish. As a result, jellyfish may be an important vector of plastic and other litter along the marine trophic web. Despite the limited size of the sample considered, the evidence shown by the study lays an important basis for future monitoring activities and to understand the mechanisms whereby plastics interact with these marine invertebrates and the potential negative effects.
 
Further information: Armando Macali, +39 329 974 4217
 
Source: Macali A., Semenov A., Venuti V., Crupi V., D’Amico F., Rossi B., Corsi I., Bergami E., 2018. Episodic records of jellyfish ingestion of plastic items reveal a novel pathway for trophic transference of marine litter, Scientific Reports 8: 6105.  DOI: https://doi.org/10.1038/s41598-018-24427-7

Last Updated on Monday, 06 August 2018 15:38