Plastic has made its way into the food webs of Earth’s remote islands in Antarctica. Scientists have recently detected traces of polystyrene in the guts of springtails, a tiny bug-like animal, along the shores of the Fildes Peninsula on King George Island. Reported in the journal Biology Letters, it’s the first time researchers have found field-based evidence that plastics are entering food webs in Antarctica.
The researchers sniffed out traces of polystyrene within the digestive tract of a springtail species known as Cryptopygus antarcticus using an infrared imaging technique. The plastic fragment appeared to have been colonized by algae, moss, and lichens, suggesting it had been eaten up by the animal during its typical grazing.
Springtails (aka collembola) are soil-dwelling invertebrates that are a mere millimeter in length. Despite their small stature, scientists are particularly interested in them as they play an integral role in the soil food webs of Antarctica.
“The fact that one of the most abundant collembolans in remote Antarctic soils is ingesting microplastics implies that these anthropogenic materials have deeply entered the soil food web,” the study authors write.
The researchers fear their discovery could indicate that plastics are making their way up the food chains of Antarctica. Microplastics are broadly known to be passed up the food chain since they do not biodegrade: plastic is consumed by zooplankton, small fish eat the zooplankton, and a larger fish eats the smaller fish. Due to this accumulation effect, microplastics can start to accumulate in the larger predators at the top.
While microplastics are still yet to be discovered in Antarctica's larger beasts, the discovery of microplastics in the belly of springtails suggests the starting links of the chain are already in place.
"Cryptopygus antarcticus has a key role in the simple Antarctic terrestrial food webs,” Elisa Bergami, lead author and marine ecologist from the University of Siena in Italy, told AFP news agency.
“The implications of plastic ingestion by this species include the potential redistribution of microplastics through the soil profile and transfer to their common predators, the moss mites.”
Fildes Peninsula, where this specimen was taken from, is said to be one of the most contaminated regions of Antarctica due to its proximity to scientific research stations, airport facilities, and tourism. Nevertheless, the discovery still comes as a surprise. After all, it was just a couple of months ago that scientists reported the presence of microplastics in the sea ice of Antarctica for the first time.