A new study led by researchers at British Antarctic Survey (BAS) discovered microplastics in krill (Euphausia superba), a small shrimp-like crustacean, and salps (Salpa thompsoni), a gelatinous marine invertebrate. The results are published today (Wed 29 March) in the journal Royal Society Open Science. Whilst Antarctic krill have been observed ingesting microplastics in laboratory settings, the team’s findings provide important evidence that these animals, as well as other zooplankton, ingest plastic in their natural environment.
Microplastics are present in the Southern Ocean from the sea surface to seabed. Due to the small size of these particles (<5 mm), Antarctic zooplankton are likely to mistake the plastics for their natural food source. The team focussed on two of the most abundant species of Southern Ocean zooplankton: Antarctic krill, and salps. These two species are critical to the diet of much of the Southern Ocean’s marine wildlife. Krill is the main food source for whales, penguins, and seals whilst salps are eaten by some fish and larger marine birds.
Krill and salp samples were collected onboard the research ship RRS James Clark Ross on two research missions off the Northern tip of the Antarctic Peninsula in 2016 and near the island of South Georgia in 2018. Microplastics were extracted from both species with plastic microfibres most common. One of the largest sources of these fibres is shedding from clothing during washing and drying. Around 60% of the krill and salps contained nylon, a microplastic with significant commercial applications in clothing, fishing gear, ropes, and reinforcing car tires.
Read more at British Antarctic Survey
Image: Antarctic krill, small crustaceans, are filter feeders eating phytoplankton and other microscopic organisms. (Photo Credit: Pete Lens (BAS))