Structure of the suprabenthic assemblages in
the Capbreton area (SE of the bay of Biscay)
Laure Corbari, )ean-Claude Sorbe
Umversité de Bordeaux 1, laboratoire d’océanographie biologique, UMR-CNRS-EPOC 5805,
2 rue du Pr Jolyet, 33120 Arcachon, France
sorbe@biocean.u-bordeaux.fr
Abstract
The suprabenthic communities from the Capbreton area were sampled
in a few stations located within the upper canvon, on its northern adjacent shelf and open slope. The analysis of the fauna sampled shows that
the canv on communities are structurally different from the slope ones,
probably due to distinctive environmental conditions at the sedimentwater interface related to the peculiar canyon morphology. The local
abundance of a few rare taxa corroborates the concept of “canyon indicator species” previously defined for such deep environments.
Résumé
Les communautés suprabenthiques du secteur de Capbreton ont été
échantillonnées en diverses stations situées sur la plate-forme, dans le
canvon et sur la pente. L’analyse de ce matériel montre que les communautés profondes du canvon présentent des caractéristiques structurales distinctes de celles de la pente adjacente, probablement liées aux
particularités locales des eaux de fond dans cette portion étroite et
sinueuse de la fosse. Certaines espèces y sont relativement abondantes,
confirmant ainsi l’existence de «canyon indicator species » déjà mises
en évidence dans ce type d’environnement profond.
Introduction
According to the definition given by Brunel et al. (1978), suprabenthos includes bottom-dependent animals (mainly small-sized crustaceans) that swim at least periodically in the near-bottom environment
and can perform vertical migrations on a regular daily or seasonal basis
into the water column. Suprabenthic animals are known to be an important source of food for many demersal fishes, at least during their
juvenile phase (Sorbe, 1981). However, their trophic role in benthic ecosystems has been probably underestimated because they are inefficiendy
sampled by grabs and box corers. Due to their swimming ability, these
animals need to be sampled by specific gears equipped with plankton
nets and towed over the sea floor at an appropriate speed.
In the SE of the bay of Biscay, suprabenthic assemblages were mainly
studied at the latitude of Arcachon on the shelf (Sorbe, 1982, 1984,
87
the Capbreton area (SE of the bay of Biscay)
Laure Corbari, )ean-Claude Sorbe
Umversité de Bordeaux 1, laboratoire d’océanographie biologique, UMR-CNRS-EPOC 5805,
2 rue du Pr Jolyet, 33120 Arcachon, France
sorbe@biocean.u-bordeaux.fr
Abstract
The suprabenthic communities from the Capbreton area were sampled
in a few stations located within the upper canvon, on its northern adjacent shelf and open slope. The analysis of the fauna sampled shows that
the canv on communities are structurally different from the slope ones,
probably due to distinctive environmental conditions at the sedimentwater interface related to the peculiar canyon morphology. The local
abundance of a few rare taxa corroborates the concept of “canyon indicator species” previously defined for such deep environments.
Résumé
Les communautés suprabenthiques du secteur de Capbreton ont été
échantillonnées en diverses stations situées sur la plate-forme, dans le
canvon et sur la pente. L’analyse de ce matériel montre que les communautés profondes du canvon présentent des caractéristiques structurales distinctes de celles de la pente adjacente, probablement liées aux
particularités locales des eaux de fond dans cette portion étroite et
sinueuse de la fosse. Certaines espèces y sont relativement abondantes,
confirmant ainsi l’existence de «canyon indicator species » déjà mises
en évidence dans ce type d’environnement profond.
Introduction
According to the definition given by Brunel et al. (1978), suprabenthos includes bottom-dependent animals (mainly small-sized crustaceans) that swim at least periodically in the near-bottom environment
and can perform vertical migrations on a regular daily or seasonal basis
into the water column. Suprabenthic animals are known to be an important source of food for many demersal fishes, at least during their
juvenile phase (Sorbe, 1981). However, their trophic role in benthic ecosystems has been probably underestimated because they are inefficiendy
sampled by grabs and box corers. Due to their swimming ability, these
animals need to be sampled by specific gears equipped with plankton
nets and towed over the sea floor at an appropriate speed.
In the SE of the bay of Biscay, suprabenthic assemblages were mainly
studied at the latitude of Arcachon on the shelf (Sorbe, 1982, 1984,
87