Search

An examination of some benthic amphipods belonging to the genus Cheirocratus from Arcachon Bay revealed that they exhibited a combination of morphological character states that distinguished them from all previously described Cheirocratus species. In the form of the gnathopods, Cheirocratus pseudosundevallii is very close to two other European species: C. sundevallii and C. intermedius. An actualized key to the species of Cheirocratus is provided. [ABSTRACT FROM AUTHOR]

Hermit crabs are well-known to shelter many epibiotic, endobiotic or endolithic species in their shell, and examination of shells inhabited by hermit crabs in Arcachon Bay reveals the presence of several such species. Among them is the amphipod Monocorophium acherusicum , a species originally described from European waters and now known to be well distributed throughout the world, but not previously recorded to be commensal with hermit crabs, as reported herein. [ABSTRACT FROM AUTHOR]

Dans le bassin d’Arcachon, chercheurs et acteurs locaux construisent une réflexion commune autour du risque de submersion marine, largement avéré, et de ses modes de gestion. Ceux-ci oscillent entre la gestion dure sous forme d’endiguements ou d’enrochements actuellement appliquée et une gestion souple passant par des dépoldérisations de degré et d’ampleur variés. Par sa vision tant comparée que multiscalaire, le programme Barcasub (Liteau, MEDDE) vise à favoriser des échanges locaux et à juger de la pertinence ou non d’une dépoldérisation, à différentes échelles. Les politiques et les usages des polders du sud-est du bassin d’Arcachon ont pris une orientation environnementale très marquée dans le bassin depuis les années 1970. Pour autant, on ne peut parler d’une écologisation des représentations sociales du risque de submersion et de la dépoldérisation. Ce mode de protection souple du littoral participerait en effet à une transformation des modes de gestion des polders ou des usages du territoire qui n’est pas souhaitée par tous les acteurs locaux. Il conduit également à s’interroger sur le dispositif plus général de protection des rives du bassin, par des digues ou des modes de protection alternatifs, actuellement en voie d’établissement. À travers son approche comparée et multiscalaire des polders, le programme Barcasub vise à déterminer dans quelles conditions et à quelles échelles d’action la dépoldérisation pourrait s’avérer pertinente.

In the Arcachon Bay, researchers and local players are reflecting together on the ways to deal with the broadly acknowledged risk of coastal flooding and its management methods. The latter waver between the currently implemented harder management method and a softer one based on different levels of depolderisation. The depolderisation technique is being investigated through an interdisciplinary, comparative and multiscalar approach. If handling risks of coastal flooding through depolderisation may seem paradoxical, scientific studies have highlighted the interest of this defence approach, especially to curb swell and reduce defence costs. In the south-eastern part of the Arcachon Bay, the Barcasub programme (Liteau, MEDDE) is thus investigating the positive and negative effects of potential management methods as regards defence, economics, landscapes and ecology. Locally, the policies and uses regarding reclaimed areas have turned markedly green since the 1970s. However, both the social perception of the risk and of depolderisation, cannot be said to have turned green as well. In fact, this defence method would certainly lead to a change in polder management or in territorial uses. The study also leads us to reflect on the overall defence of the Arcachon Bay currently in process through hard and soft coastal protection measures. Through its comparative as well as multiscalar approach of the reclaimed areas, our research programme aims to establish the scales at which depolderisation actions could be relevant. [ABSTRACT FROM AUTHOR]