Greenpeace Expedition Finds Microplastic Levels in the Sargasso Sea Comparable to Great Pacific Garbage Patch
August 21, 2019
© Shane Gross / Greenpeace
St. George’s, Bermuda, 21 August, 2019 – A team of Greenpeace scientists has discovered extreme concentrations of microplastic pollution in the North Atlantic Ocean during an expedition to the Sargasso Sea, a critical nursery for baby turtles and other wildlife.
In one sample, the team found 1,298 fragments of microplastic, which is higher than the levels found in the Great Pacific Garbage Patch, now estimated to be twice the size of France. The Sargasso Sea is one of five global ocean gyres that accumulate land-based plastic pollution due to circulating currents. Infrared analysis done on board the Greenpeace ship Esperanza, which is on a Pole to Pole expedition highlighting threats to the ocean, indicates this pollution originates from single-use plastic bottles and plastic packaging.
“The beautiful deep blue waters out here look incredibly pure, but the manta trawls for microplastic we’ve been doing tell a different story,” said Greenpeace Spain Plastics Campaigner and marine biologist, Celia Ojeda.
“The samples we’ve gathered give us crucial data on the density of plastics on the surface of the sea. It’s grim news, but so far we can already say that the quantity of microplastics we’ve found is similar to, and in some cases exceeds, samples that we did last year in the so-called Great Pacific Garbage Patch. Turtles, eels, and other wildlife use the Sargasso Sea as a nursery, but that safe haven is now under threat from plastic.”
The microplastics research is part of a broader program of science conducted in partnership with the 5 Gyres Institute, University of Florida, the Scripps Institution of Oceanography, and in consultation with the Bermudian government. The team’s mission is to document the importance of the Sargasso Sea for vulnerable species, and to assess how this ecosystem is being impacted by plastic pollution. Scientists from the University of Florida collected data that may help determine whether the Sargasso Sea’s iconic floating Sargassum seaweed mats provide a thermal advantage to baby sea turtles, possibly serving as an incubator that helps them develop.
“We were delighted to undertake research complementing Greenpeace’s campaign in this important yet understudied habitat,” said Nerine Constant, a doctoral student at the Archie Carr Center for Sea Turtle Research at the University of Florida. “We found that water temperatures were higher inside Sargassum mats than in neighboring open water, and further analysis will determine the significance of this difference and the potential benefits to sea turtles’ development.”
The expedition is part of Greenpeace’s ambitious Pole to Pole expedition aimed at highlighting the many threats to the ocean – from the Arctic to Antarctic – and the need to protect international waters under a new Global Ocean Treaty.
”Without a new ocean treaty there is simply no way to protect special ocean places like the Sargasso Sea that lie mostly in international waters,” said Arlo Hemphill, Greenpeace USA Senior Oceans Campaigner, who led the Sargasso Sea science expedition. “This treaty would allow us to set places like this aside as fully protected ocean sanctuaries, giving them time to recover from threats like overfishing and the impact of vessel traffic so they are better able to cope with the plastics crisis.”
The third round of negotiations for a new Global Ocean Treaty is taking place at the United Nations from 19–30 August.
Photos can be accessed here.
Further information on the scientific work during the expedition:
The scientific team on board also sought to document the unique biodiversity that can be found in these waters, and to better understand the range of species impacted by plastics. To collect species data, the team used visual surveys from the ship and within Sargassum mats, a technique called blackwater photography to document deepwater species that migrate to surface waters during the night (see images). Additionally, eDNA tests allowed researchers to detect a broader range of marine wildlife which have passed through the waters in the preceding 48 hours. In addition to the microplastics work, water samples were collected to test for microfibers – the results of which are awaiting laboratory analysis.
Pole to Pole Expedition: Map of the ‘Pole to Pole’ route. See contacts below for expedition inquiries, including for media interested in joining the ship on-board.
Greenpeace and scientists are calling for a treaty that can create a network of ocean sanctuaries covering at least a third of the global oceans by 2030. For more information seeProtect the Global Oceans: Why We Need a Global Ocean Treaty. The third of four rounds of negotiations towards a treaty covering international waters is taking place at the United Nations in New York from 19–30 August, with the treaty process set to conclude with a fourth and final round in the first half of 2020.
Julia Zanolli, Greenpeace International, [email protected], (+44) 797 276 9107
Crystal Mojica, Greenpeace USA, cmo[email protected], 646-530-1581
Ana Martinez, Greenpeace Spain, [email protected], (+34) 638 101 739
Greenpeace International Press Desk, +31 (0)20 718 2470 (available 24 hours), [email protected]