Polarstern came back from the Arctic to its homeport Bremerhaven last week. During shipyard time there are not bloggers on board. Time for us to look back to the so-called AWI Hausgarten. Biologist Melanie Bergmann reports on her work about plastic litter.
Post from the Arctic in August 2015
I am Melanie Bergmann and I work on epibenthic megafauna, meaning the pretty larger animals that live on the seafloor, such as sea cucumbers, shrimps, starfish and sponges. Of course, this work can be done by trawling but I prefer to take photographs of the seafloor to see what lives there because this does not damage the seabed and animals.
In 1999, the Deep-Sea Research Group of the AWI established the deep-sea observatory HAUSGARTEN. It’s close to Svalbard, in the Arctic. One aspect of the work that we do is to study the epibenthic megafauna by visiting the same spots on the seafloor every year. I use a camera, which is towed from the ship. By comparing the images taken in different years I can tell if there are changes in the bottom community. Of course, these kinds of studies are particularly important in an area that is so exposed to the effects of global warming.
But during my studies of bottom animals on photographs, I became aware of another emerging environmental problem: the amount of man-made litter on the seafloor has increased, even doubled in the small time frame of 10 years! Luckily, it is by no means a Garbage Patch (as yet) but the quantities are actually higher than those observed, for example, in the Lisboa Canyon, close to the industrialised Portuguese capital. By going through newer images from the last three years, my M.Sc. student just found out that this trend is still on the rise and that other parts of the observatory are affected in the same way. It looks as if we do have a pollution problem in the Arctic. When looking for images for a presentation I came across this blog showing polar bears feeding on litter left behind by a Russian submarine, which saddened me.
So, of course when I do new camera transects, I dread observing new pieces of litter. Over the last few weeks, we put out our deep-sea camera at three stations along a latitudinal gradient during this expedition, and found new litter items on the seafloor: pieces of a beer bottle, string, glass, fisheries net, a plastic bag and bits of plastic. Our detailed image analysis will show if the trend is still on the increase! During this expedition, we will also carry out experiments with a remotely operated vehicle to look at the effects of litter on the deep-sea fauna.
As the sea ice retreats it opens up to shipping traffic such that more and more commercial ships and cruise liners operate in the area. The number of fishers in the region has also increased. It is only timely that a Polar Code was recently passed at a meeting of the International Maritime Organization (IMO). It comes into force in 2017 and bans ships from releasing oil, sewage, chemicals and waste into the sea. But of course, the majority of litter comes from land, so the problem needs to be tackled here, too. Our waste may be transported over long distances to the North.
If you want to find out more about litter in the sea, have a (free) read through the book ‘Marine Anthropogenic Litter’ that I published in June with Lars Gutow, a colleague from AWI and Michael Klages.