Distribution and installation dynamics of Undaria pinnatifida, a non-indigenous species of algae in Brittany (Ecokelp ANR 2007-2009 and Interreg IVA Marinexus Programmes 2010-2014)

Undaria pinnatifida, brown micro-algae also known as wakame, was deliberately introduced in Brittany to be grown as a crop, and started to grow wild at the end of the 1980s. Two programmes, Ecokelp (2007-2009) and Marinexus (2010-2014) focus on the dynamics of the distribution of this algae which is not native to Brittany. ECOKELP aimed to better understand the dynamics of micro-algae forests, and Undaria pinnatifida was one of the project’s target species. MARINEXUS aimed to study marine ecosystems trans-channel, and a “workpackage” was dedicated to non-indigenous species, including Undaria pinnatifida. Both of these projects aimed to create an inventory of the presence of Undaria pinnatifida in artificial habitats (ports, marinas, etc.) and natural settings along the Breton coast, by surveying and then comparing data with the literature. Specific focus was on the bay around Mont Saint-Michel, Lampaul (Ushant), l’Aber Wrac’h and Morlaix bay. Observations, micro-mapping, and genetic analyses were conducted during the programmes. A PhD thesis (Daphné Grulois – UPMC ; dir. F. Viard – Station Biologique de Roscoff; contact : viard@sb-roscoff.fr) brings together and summarises the data, observations, inventories and maps created throughout the Ecokelp programme. It is available at: http://www.sb-roscoff.fr/images/stories/sbr/Edition- communication/theses/Grulois_thesis.pdf