Krill is not only an important food source for countless marine animals, the tiny crustaceans could also prove to be a secret weapon in the fight against ocean plastic pollution, according to Australian researchers. Barbara Barkhausen reports from Sydney.
Many animals are dying miserably from plastic pollution in the world’s oceans. Krill, on the other hand, seem to have declared war on plastic waste.
New research from Australia shows that these tiny zooplankton are capable of digesting microplastics before excreting them back into the environment in an even smaller form.
After digestion, the fragments were on average 78 per cent smaller than the original beads, with some even reduced by 94 per cent.
These tiny crustaceans are turning microplastics into nanoplastics, according to the study led by environmental scientist Amanda Dawson from Griffith University in Brisbane. The research, which has now been published in the journal Nature Communications, is causing ripples in scientific circles.
Dawson told the Australian news service ABC that she was herself “extremely surprised” by the results.
“It took me a long time to believe my results actually, I went back and re-tested over again,” she said.
“It was pretty mind-blowing when we found out krill could break up plastics into tiny pieces.”
An enormous filter
The study was conducted on Antarctic krill, and researchers estimate there is up to 500 million tonnes of krill in the Southern Ocean. Each creature is capable of filtering up to 86 litres of seawater a day, making them an “enormous filter” in breaking these plastics down.
What’s lesser known is how the toxins in the plastic behave and the possible impact they have on the krill themselves.
The researchers also warn that their finding could be a double-edged sword, as the toxins could be passed down the food chain as smaller excreted particles become available to organisms that would not be able to ingest larger ones.
“We’ve barely scratched the surface and more work is needed,” Dawson told AFP.
The terrible extent of ocean plastic pollution was back in the spotlight last week after British diver Rich Horner posted a video of himself swimming under a thick ceiling of plastic waste floating on the water’s surface and diving through floating bits of plastic: bags, bottles, cups, sachets, straws and more.
The footage was shot off the coast of the island of Nusa Penida, around 20 kilometres from the popular Indonesian holiday island of Bali, at Manta Point, a renowned dive spot and station where manta rays come to get cleaned of parasites by smaller fish.
In the video, Horner spots just one manta ray.