Since we left the coast of Tenerife and the proximity of the Sahara, dust has cleared from the sky. The foggy clouds around us have made space for a clear blue sky with some occasional clouds. This makes forgreat photography, especially during sunrise, sunset and moonrise. In a span of 24 hours, we come across endless variations of blue, pink and orange.In the doldrums the water became flat as a mirror, reflecting the light beautifully. On clear nights we can finally observe the stars. We are lucky to have Ali on board, who knows many Arabic stories on the stars and constellations.
Next to the beauty of the physical, we still very much enjoy the animals we are surrounded by. For example, our hitchhiking friends “Claudia Bunt & Thomas of the Foremast”. It has been spectacular to see them catch flying fish straight out of the water or to observe them from up close, which we luckily can if we climb up the masts. Since then, our bird army has expanded to a flock of 7, all from different species. Some of them enjoy the possibility to occasionally sit on our masts for a little break, something we enjoy a little bit less.
Especially those of us who have been in the wrong place at the wrong time when the birds did their number 2. Furthermore, we recently got a very good view of a group of bonitos swimming along with the ship at incredible speed. As could be expected, there were some who wanted to have an even closer look, so the fishing rod was taken out of the closet. Two bonitos were successfully caught, closely observed and later eaten in a delicious salad.
Regarding fishing, we have also been fishing for science. We have a net on board which we can use to catch plankton, and a ‘manta troll’, which we are using to research the abundance of floating plastic. Next to the research on plastic, we find a lot of life in the nets as well; the diversity has been incredible. At night, we found fish capable of bioluminescence, common for species that spend their days in the deeper darker twilight zones of the ocean. For some of the voyage crew this raised a lot of questions: what else is living underneath us?
To understand a little better what is going on below the surface, I organised a lecture on the deep sea. Next to deep sea fish, we also found a lot more plankton in our nets at night.
The difference has been mind-blowing and can be explained by the phenomenon diurnal vertical migration. Many species live at depth during the day (varying from 200 to 800 meters) and swim to the surface at night to feed. In terms of biomass, it is the largest synchronous migration in the world. I find it amazing we can see this first hand during our trolls.
It is quite special in any case; for an organism that is 2 mm long, a 200-m migration is the rough equivalent of a 200-km swim for a human! To be fair, they are good swimmers. But still: why do they do this?
Our voyagers can tell you all about the possible hypotheses when they get home. And when they get home, they will probably also tell you about Neptune’s visit. I will not give anything away in this blog, but we I can say we have crossed the equator.
More on our adventures in the southern hemisphere will follow soon!
