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Photo of Meinesz Alexandre Meinesz
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Alexandre Meinesz was born on April 12, 1946, at Cagnes-sur-Mer (Alpes-Maritimes) France. Since 1989, Meinesz has been a professor of Biology and Director of the Marine Coastal Ecology (Littoral Environment) Laboratory at the University of Nice - Sophia Antipolis. Meinesz obtained his Ph. D. in Phycology (the study of algae) from the University of Paris VI in 1980.

Meinesz is a professional diver who has performed more than 3000 dives since 1967 in the Mediterranean Sea, the Pacific Ocean, the Red Sea, the Persian Gulf, and the Atlantic Ocean. He is also an Aquanaut who has visited the NOAA underwater house, "Hydrolab" in the Virgin Islands. A Captian (Lieutenant de Vaisseau) in the french Navy, Meinesz has performed 18 dives in the pocket submarine "Griffon."

Meinesz is the author of 160 scientific publications about Seagrasses, Algae and Caulerpa, introduced species, mapping, survey and monitoring systems for littoral underwater ecosystems and impacts of construction on the sea floor.


For links to this scientist's home page and other related information please see our resources page

Meinesz responds :

11.06.01 Corri asks:
Bonsoir M. Meinesz- Has the French/Euro government given you permission to try the Florida slugs on the invasive weed? How have the lab tests proceeded? Finalement, how many years do you predict it will take the slugs to eradicate the aquarium plant?
Merci pour votre reponse.

Meinesz's response:
Bonsoir Corri!
No, the French and other governments have no interest in our slugs. Regarding our recent scientific publications on this biological agent versus Caulerpa taxifolia, we hope that next year we can organize a meeting with a number of international experts under the auspices of the French Environmental Agency. This is to allow the first experiments in the open sea with the cold intolerant slugs from Martinique. In the same year, we also hope to collaborate with the University of Florida to catch and study other, more cold tolerant populations of Elysia subornata. We have still a little hope that the slug will significantly reduce the alga!
Merci pour votre bonne question!

11.07.01 Danielle asks:
Are there more pictures online of the Caulerpa weed and slug that eats it?

Meinesz's response:
Bonjour Daničle (Nice French name!) Try where there are about 60 pictures of Caulerpa. We must get more of the slugs !

11.09.01 Kevin G.asks:
Are there any definitive books about the Caulerpa taxifolia crisis in the Mediterranean Sea?

Meinesz's response:
Bonjour Kevin
Yes, I wrote a book called "The Killer Alga" in which the whole story of the crisis is described! Editor is Chicago University Press. Enjoy the book!

11.08.01 Malarie asks:
Do you have any leads to a solution for the algae problem in San Diego? If So, would this help the Mediterranean?

Meinesz's response:
Bonjour Malarie (this is an uncommon first name in France, but I think it sounds very nice!)
I think that in San Diego, the local authorities do their best to control the Caulerpa. They use chlorine. This was also proposed by a company in France in 1992. but it was forbidden by the French Agency of the Sea (IFREMER). Now, it seems to be working at San Diego. I'll be visiting San Diego at the end of January for an international meeting. I hope to learn about their control methods . I think it can also work in France to prevent colonization of other underwater sites.
All the best

11.07.01 Paul B asks:
If the Caulepra is growing in international waters, could you release the slug with out permission from any government? Since the slug is highly specialized to eat only Caulerpa, won't they just starve to death when the food supply is gone, ending any threat they might have posed to the environment? How many slugs would it take and how long before they would actually start making a sizeable dent in the Caulerpa population?

Meinesz's response:
Hey Paul, this is a good question ! You are right, if we release the slug in France, it will very quickly find its way to other countries! So, it must be an international decision to put it even in French waters. Yes absolutely: since the slug is highly specialized to eat only Caulerpa, the slugs just starve to death when the food supply is gone, ending any threat they might have posed to the environment. They can survive about 30 days without any Caulerpa using the chloroplasts stored under their skin, which provide enough energy and sugar to last the slug for one month! (This is kleptoplasty and endosymbiosis of chloroplasts).

We estimate that releasing a few hundreds in early spring would be enough to control a population of Caulerpa in a bay of some hectares. These results can be observed in early autumn, when the population of snails would be in the third generation (each lays 400 eggs/week and the babies reproduce after 2 months!). All the best

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