Behavioral responses of Crassostrea gigas exposed to the harmful algae Alexandrium minutum

• Published in: Aquaculture
• Main Authors: Tran, Damien, Haberkorn, Hansy, Soudant, Philippe, Ciret, Pierre, Massabuau, Jean-Charles
• Other Authors: Environnements et Paléoenvironnements OCéaniques (EPOC), Observatoire aquitain des sciences de l'univers (OASU), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-École Pratique des Hautes Études (EPHE), Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), Laboratoire des Sciences de l'Environnement Marin (LEMAR) (LEMAR), Institut de Recherche pour le Développement (IRD)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Université de Brest (UBO)-Institut Universitaire Européen de la Mer (IUEM), Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2010
• Subjects: Crassostrea gigas; Alexandrium minutum; Valve activity response; Harmful algae; [SDE]Environmental Sciences
• Online Access: https://hal.univ-brest.fr/hal-00645621; https://doi.org/10.1016/j.aquaculture.2009.10.030

International audience We describe the valve-activity behavior of oysters, Crassostrea gigas, exposed experimentally to the harmful alga Alexandrium minutum (≈ 3500 cell ml− 1) for 7-day periods under laboratory conditions. Our aim was to assess behavioral responses of oyster species during a mimicked bloom exposure. We determined different characteristic parameters of valve activity, such as daily valve opening duration, daily number of micro-closures, and valve-opening amplitude using a High Frequency-Non Invasive valvometer. In comparison with oysters exposed to non-toxic algae, T-Isochrysis or Heterocapsa triquetra, the valve activity of C. gigas is measurably different when exposed to toxic algae A. minutum. Surprisingly, daily valve-opening duration increased, as well as micro-closure activity, while valve-opening amplitude decreased. The response to A. minutum is fast, within 1 h after algae exposure. Following A. minutum exposure, recovery to control patterns was observed within 4-5 days. The behavioral alterations upon exposure to A. minutum can be thus used as a complementary physiological variable to other well-established physiological and biochemical measurements.