Expedition: stopover in Cape Verde

, -

The crew of Blue Observer reached the island of São Vicente in the Cape Verde archipelago on Tuesday 22 February at 2am (local time) after 24 days at sea from the island of Saint Helena. It is a total of 82 days at sea that our sailors and scientists have shared together on board Iris.

This stopover in Cape Verde will allow for a crew change before setting sail again to Brest, the yacht’s home port. Iris should point the tip of its bow in the roadstead of Brest around March 10 – 15. During this last stage, microbiology activities will continue on board.

Deployment of 95 Argo floats, a world first

This is the first time in the world that such a large quantity of floats has been deployed under sail. The 95 Argo profiling floats deployed are operational and have started their life cycles in the oceans. They measure the salinity and temperature of the water at well-defined locations and sail with the currents to provide scientists with accurate data.

Deployment preparation
Float deployment
Float in water

Relive the deployment of the last float in pictures:

Microbiology on board Iris

Aerosol and marine samples are being taken all the way to Brest. We have developed protocols for collecting phytoplankton from aquatic and aerosol samples.

Within the framework of the partnership with the Roscoff Biological Station, we are currently creating a “Souchothèque” (sample library) which will store hundreds of strains of marine microorganisms (genetically characterized and isolated).

It will then be used as a basis to identify molecules of interest for the marine biotechnology industry, as phytoplankton represents an immense potential for innovation in the health, nutraceutical and cosmetic industries.

Discover the sampling protocols that Eloïse Le Bras uses on board to collect marine and air plankton:

Cetacean watching

The navigation was punctuated by encounters with marine mammals in the Gulf of Guinea: humpback whales, clymene dolphins, white spotted dolphins, etc. All observations were carefully recorded and sent to WHOI as part of the marine mammal study.

Cetacean watching
Cetaceans watching

Navigation logbook

As they rounded the island of St. Helena on January 28 to head southeast, a strong southerly wind threw the crew back into upwind sailing. For more than a week, the wind faced Iris which adapted its trajectory to the deployment plan of the floats.

The first turn to the west marked the beginning of the great return journey. The SE wind remained present and the crew quickly hoisted the spinnaker allowing them to sail downwind. After several weeks at heel, the sailors on board have learned not to live leaning anymore. As the boat sailed up the Atlantic Ocean towards the equator, our sailors once again tasted the muggy heat of these latitudes. The daily life on board was punctuated by multiple encounters: a school of tuna that followed Iris for several days over dozens of miles, playing like dolphins at the bow of the boat, and numerous flying fish in particular. The fishing of a dolphinfish made the event on board.

The road continued through the doldrums. The crew faced the vagaries of the inter-tropical convergence zone before continuing their route to the Cape Verde archipelago.

Sailing boat in navigation

Oceanography under sail, a viable model

The crew is formal : our sailboat Iris is reliable, safe, fast and adapted with a great autonomy to sail. The transformation of Jean-Luc Van Den Heede’s racing boat into an oceanographic sailing boat is a success.

Oceanography under sail answers many problems and opens a new field of possibilities. The advantages of our sailboat:

Economic: the daily sea cost is a fraction of the cost of a motor boat. The autonomy of the sailing propulsion allows to navigate in remote maritime areas.

Clean: Sailing is carbon-free and environmentally friendly. It avoids any polluting discharge in water or air and allows the collection of uncontaminated microbiological samples.

Flexible: the size of our boat and the agility of our structure allow us to prepare missions quickly.

Silent: the acoustic impact of a sailboat is very limited and avoids disturbing the marine fauna. This allows us to carry out observation missions, especially of cetaceans, in ideal conditions.

Photo credits: ©Baptiste Langlois Meurinne