Bay of Marennes - Oléron, FranceThe site was only emersed during a couple of hours at low tide. No way to have a telegraph pole! Consequently, we set a fully waterproof HFNI valvometer, programmed to give us a ring at low tide. The left picture below shows the in-situ set up on a bench. In the bottom, an oyster farm. The electronic was in the grey tube. It was composed of our home made mini µPC, equipped with the core of a mobile phone and an antennae. Everything was developped, build and programmed by our laboratory (UMR 5805 EPOC) and the EUKREA Télématique company, Pessac, Gironde. Two batteries are on the left. One half of the oysters was in a traditional oyster bag (covered by algae) on the right of the grey tube. The other half was set on the floor, lightly attached to a piece of oyster bag, independently of the recording cables. All records were published dailly on our website, the MolluSCAN Eye.
Spawning in female oysters is very typical. It is characterized by a series of contraction occurring first every 20 seconds. A series last from 20-30 minutes. Male behaviour is quite different. Fundamental: fecondation occurs in water, all partners must be perfectly synchronized ! Amazing: Oysters are alternatively male and female. This record was caught on july 23th, 2009, at 5:35 a.m., in a female oyster freely living in the Bay of Marennes.
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ZOOM: Hover over the graph with the mouse cursor, left click and drag to zoom in. Today, one have a resolution of 100 msec and ~ 1 µm
. Ny Alesund, 79°N . 22/1/2016: 3 years & 9 months at sea!!!
to see how it is at 1300km from the North Pole, select "Gallery" from the menu bar and "Localisations" from the pulldown menu