Trawl nets endanger many species
In Marine Protected Areas (MPAs), the marine environment should be particularly protected. As a recent study, published in the journal Science, shows, about 60% of these MPAs have to deal with trawls, with (sometimes) significant negative impact on species living there.
Almost 30% of European marine waters are designated as protected areas. This sounds reassuring, but does not mean that there is no commercial use in these areas, for example by fishing. Trawling is permitted in many of the so-called MPAs, with considerable negative effects, as a recent study by German and Canadian scientists recently published in the journal Science has shown.
Researchers studied more than 700 MPAs in European waters around the British Isles, the North Sea, France and Spain (excluding the Mediterranean). Analysis of satellite data revealed that trawl intensity in MPAs was on average 40% higher than outside protected areas. "We show that the number of different shark and ray species in areas with high trawling is up to 69% lower," explains Manuel Dureuil, lead author of the study from Dalhousie University. "These are often bottom trawlers, which can also have negative effects on other organisms."
"Our study shows that bottom trawling marine protected areas are no safe procedures, but that endangered species are in some cases more threatened there than outside these areas, which is completely nuts" Dr. Rainer Froese, co-author of the study by the GEOMAR Helmholtz Center for Ocean Research Kiel explained. "So that protected areas deserve their name, bottom trawling has to be stopped," continues Froese. In his view, there is no need for commercial fisheries in the MPAs. If fish stocks were managed sustainably, stock sizes would grow and the permitted catches could easily be fished outside of MPAs, according to the Kiel fishery biologist.
The scientists therefore demand that the minimum standards of MPAs be urgently improved. Politicians must agree on internationally comparable standards excluding bottom trawling and the management of MPAs needs to be strengthened and made more transparent. Only in this way can MPAs be able to contribute in the long term to sustainable protection of the marine environment and endangered species.
More Information: www.geomar.de.
Link to the study: science.sciencemag.org/content/362/6421/1403.