Flore et habitat de l’archipel Houat-Hoedic

French language text

A first version of the Flore et habitat de l’archipel Houat-Hoedic was published in 2017, but quickly sold out. Since that first edition, numerous discoveries have been made. Botany is also a constantly evolving science; the classification by family and the nomenclature have undergone changes that have been taken into account in this new edition.

Updated and enriched, this version is aimed at everyone: from visitors curious to discover the natural riches of Houat and Hoedic, to more experienced botanists who will find a detailed list of recorded species, classified according to their family.

The Houat-Hoedic archipelago, situated off the coast of Brittany, boasts remarkable ecological characteristics, linked to its protected location away from the mainland. This island setting results in an exceptionally rich flora.

The islands shelter a great diversity of habitats: freshwater to brackish ponds (notably on Hoedic), reedbeds, beaches, dunes, shingle ridges, cliffs, coastal grasslands, thickets, and some woodlands. The stabilized dune, also known as the “grey” dune due to the color of the bryophytes and lichens that colonize it, covers approximately 135 hectares across the two islands. It constitutes a natural habitat of Community interest under the European Habitats Directive (1992). This dune substrate, combined with the archipelago’s location off the southern coast of Brittany, gives its flora a Mediterranean character. Some highly unusual plant communities are found there at the edge of their distribution range.

The Morbihan coastline is home to a significant concentration of rare or declining plant species, classified as “species of high heritage value.” Two of these, the Angular Vetchling (Lathyrus angulatus) and the Ox-head Sorrel (Rumex bucephalophorus), are found only on Hoedic.
Given the small size of the two municipalities and the large number of species recorded, the density of rare and threatened plants there reaches an exceptional level.

651 species are described, 51 of high heritage value, 215 are illustrated with photographs taken on the two islands.