Weblog

<< Back

Jan 06, 2007: Plankton Research

23°C / 73°F

Position:25° 16’ 5 N-18° 49’ 2 W

Wind: 28km/h

Plankton research reveals a very rich spectrum of species

This morning the sky was partly cloudy. Therefore, the charging of the batteries did not show a maximum. At present time, the batteries are charged to 50 percent; but the angle of the sunrays is much better at this latitude, and considerable improvements of the charging process could be achieved in Lanzarote. Like that, a higher percentage of the solar energy can be stored now in the batteries in addition to the propulsion of the electric motors.

David Senn took up his plankton research again. Yesterday, he collected a very rich spectrum of species, among them the blue salp (phyllum of the chordata, class of tunicata), a barrel shaped animal, transparent like glass that can filter smaller plankton with its gills and use it as food. He also found Carinaria, a special pelagic snail. Carinaria is a quite large marine snail (Gastropoda). It is perfectly adapted to life in the pelagic environment. This 6 cm long animal is completely transparent, appearing like glass. Thus, it is camouflaged in the open water, an unstructured space to live. Unlike other Gastropoda (snails), it does not creep but it swims. And, compared to the basic anatomical plan of Gastropoda, it lives in a reverse position, upside down, the ventral side directed upward. Propulsion is performed by an undulating fin, which – anatomically - is a modified foot. The caudal part extends as a finlike steering organ. The animal does not develop a shell; part of the gut and the liver are concentrated in a pigmented sack; small gills extend from this place. The head shows two distinct eyes. The tube-shaped mouth extends upwards in order to catch smaller plankton. David Senn has seen this animal for the first time; but his teacher Adolf Portmann presented it in a lecture that David remembers.

Other than that, we today had a view that has not changed much since the times of Diaz, Columbus, Maghellan & Co.: 360 degrees of sea, grey-blue, with small and big foam crests ("mer agitée"). Winds from the North at a speed of 15 knots, sky cloudy, speed 4 knots. We covered 107 miles today.

<< Back