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The colour of the water has become a deep bright blue

As we have left the coast the colour of the water has become a deep bright blue, making us dream of a swimming break. In these transparent waters, we can see far below the surface, yet we don’t see much life floating by. We are sailing over a vast endless stretch of ocean, also described as the blue desert. It is not as empty as it seems; our manta trawl shows something different. There is always plastic. And there is always living creatures as well. Our first exciting find was the sea skaters (Halobates), the only known truly oceanic offshore insects. Even though they are common, I keep being amazed. There are probably between six and ten million insect species and only five of them made it to the open ocean. There is something admirable there. 

Next to sea skaters, we have also found squid, isopods, and immense numbers of blue copepods. They are interesting little creatures; they are very small, have no need for a heart or circulatory system, and often lack gills as well: instead, they can just absorb oxygen directly into their bodies. Like other crustaceans, they possess two pairs of antennae, one pair often long and used for swimming. With an estimated 14.000 species existing there is of course a huge variation in body plans. Copepods represent up to an estimated 90-97% of the total biomass of marine zooplankton, making them important actors in the functioning and shaping of aquatic ecosystems. 

With the naked eye, they look just like blue dots so in order to prove to the voyage crew they are in fact very important animals I took the microscope out. Especially the compound eyes of the isopods and sea skaters stole the show. Under the microscope clearly visible, but hard to capture with the camera. Although I have gotten quite skilled in trying to put the camera of my phone exactly in the right spot, the rolling of the ship poses an extra challenge. We only get a fraction of a second before the subject floats out of focus. It was both humorous and frustrating, gathered together around the microscope, waiting for the ship to sway the little critters back into place!  

Writing this, our morning sounds like a peaceful endeavor. Doing some trawls, picking out plastic from the sieves under the morning sun, looking at little creatures under the microscope. However, just as the manta trawl entered the water, the decision was made to put the portside studding sails up. The last two days the crew has been busy rigging all the lines, and it was time to bring the yards up. And so, I spend my morning running back and forth from the manta trawl to the fore deck, checking out what they are all doing there. By lunchtime, two studding sails were up, and the manta trawling was finished. The afternoon was occupied by setting the last studding sail and going through all the samples. Somehow Jordi managed to help with the studding sail operation, take photos of this all, and document the activities of the science club at the same time.

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