In early summer 2021, two women from Flensburg in northern Germany went fishing for microplastic in the North Sea and Baltic Sea. Nine sailing enthusiasts and a number of other volunteers assisted them in the so-called Citizen Science Project. The results will now be made available to science.

 

Caro Höschle, a biologist, and Lauren Grüterich, an engineer in energy and environment management, had the idea of setting up a voluntary research project to investigate the presence of microplastic in the sea. The two yachtswomen had in the past fished microplastic out of the Arctic Sea with a self-made filter net they call the "manta trawl". After that, they wanted to know how much microplastic was to be found at their own front door in the Baltic Sea and North Sea. In order to collect data for science over as large an area as possible, they launched a citizen science project, to which anyone interested could contribute and assist in the research. "The big advantage of citizen science is that the number of samples and the simultaneous full coverage of the Baltic and North Seas is much larger than when only one institute travels along one route with the manta trawl," explains Höschle. The volunteers involved in the project simultaneously fished for microplastic for one week from nine sailing boats on the Baltic and North Seas and on the river Elbe. To sample the waters, the project participants dropped filter nets into the water twice a day from the deck, so that they floated on the surface for a total of 30 minutes at a speed of 2.5 knots. As reported by the two initiators, the precise coordinates of the sampling points were also documented. A pre-evaluation of the samples was carried out while still on board the boats, with the crew pre-sorting organic and inorganic particles using tweezers and a microscope. Prepared in this way, the samples were sent by the nine boats to Helgoland for evaluation in a student laboratory of the Alfred Wegener Institute, which is part of the Helmholtz Centre for Polar and Marine Research. There, they were examined for inorganic material with the aid of a spectrometer. More than half the specimens were identified as plastic, including polyethylene, polypropylene and polystyrene. A scientific paper is to be written on the basis of the laboratory results, so that the findings from the project can be made available to science. To what extent the results from the specimens collected from the sea and pre-sorted on board are of scientific value is, however, questionable, because contamination during sampling is also a frequent source of error in scientific microplastic studies.

 

Sources:

• ndr.de (Dec. 26, .2021)
• Photo: © weniger-ist-meer.com