Jellyfish dining out on diet of microplastic pollution

11 November 2021

Jellyfish are the latest species found to be ingesting microplastics' sounding a warning of the risks of pollution to species higher up in marine food chains' including human beings.

New research from an international collaboration including CQUniversity's Coastal Marine Ecosystems Research Centre (CMERC) found almost 2 000 microplastic particles in six different species collected in the Orkney Islands north of Scotland.

Gladstone-based CMERC researcher Dr Angela Capper said the presence of microplastics in the different types of jellyfish and comb jellies was alarming given their role in marine food webs.

"Jellyfish are consumed by a range of species' from crustaceans to fish and turtles' and even human beings' with fisheries in more than 15 countries now harvesting jellyfish'" Dr Capper said.

"What we've discovered through our field sampling and laboratory trials' is that these jellyfish are ingesting mostly microfibre type plastics from food packaging' ropes' clothing and textiles.

"They are ingesting these plastics either by consuming prey already containing microplastics or by filter-feeding."

The research project was a collaboration between CMERC' Heriot-Watt University in Scotland' and the University of East London (UEL)' and its findings were published recently in the peer-reviewed scientific journal' Marine Pollution Bulletin.

Microplastics are less than five millimeters in size and produced by the breakup of larger plastic pollution' and have become increasingly problematic in the environment as global plastic production has soared from 1.5 million tonnes (mt) a year in the 1950s to 359mt in 2018.

The report noted the growing importance of jellyfish to marine ecosystems' with populations booming in some parts of the world - possibly due to over-fishing and other potential anthropogenic stressors.

Co-author' former Heriot-Watt student and now PhD student at UEL' Ms Ria Devereux' said a key insight from the North Sea research project was the dominance of blue and black microfibres' which were highly prevalent in the area and likely to have originated in waste water from urban washing machines.

The most common plastic types observed in the wild were polyester terephthalate (PET) and polypropylene (PP)' while PET was also ingested during the laboratory feeding trial.

"What we still need to investigate further is how long microplastics remain in the bodies of jellyfish or if they are excreted over time'" Ms Devereux said.

The problem of microplastic contamination is a priority challenge for the CMERC team' which was established in 2019 to work with coastal industries and communities to develop practical and sustainable solutions for coast and marine environments.