||Coquereau Laura1, Jolivet Aurelie1, 2, Hegaret Helene1, Chauvaud Laurent1
||1 : Univ Bretagne Occidentale, Inst Univ Europeen Mer, Lab Sci Environm Marin, LIA BeBEST,UMR 6539, Rue Dumont DUrville, F-29280 Plouzane, France.
2 : TBM Environm Somme, 115 Rue Claude Chappe,Technopole Brest Iroise, F-29280 Plouzane, France.
||Plos One (1932-6203) (Public Library Science), 2016-08 , Vol. 11 , N. 8 , P. e016093 (15p.)
|WOS© Times Cited
||Harmful algal blooms produced by toxic dinoflagellates have increased worldwide, impacting human health, the environment, and fisheries. Due to their potential sensitivity (e.g., environmental changes), bivalves through their valve movements can be monitored to detect harmful algal blooms. Methods that measure valve activity require bivalve-attached sensors and usually connected cables to data transfers, leading to stress animals and limit the use to sessile species. As a non-intrusive and continuously deployable tool, passive acoustics could be an effective approach to detecting harmful algal blooms in real time based on animal sound production. This study aimed to detect reaction changes in the valve movements of adult Pecten maximus exposed to the toxic dinoflagellate Alexandrium minutum using both accelerometry and passive acoustic methods. Scallops were experimentally exposed to three ecologically relevant concentrations of A. minutum for 2 hours. The number of each type of valve movement and their sound intensity, opening duration, and valve-opening amplitude were measured. Four behaviours were identified: closures, expulsion, displacement, and swimming. The response of P. maximus to A. minutum occurred rapidly at a high concentration. The valve activity of P. maximus was different when exposed to high concentrations (500 000 cells L-1) of A. minutum compared to the non-toxic dinoflagellate Heterocapsa triquetra; the number of valve movements increased, especially closure and expulsion, which were detected acoustically. Thus, this study demonstrates the potential for acoustics and sound production changes in the detection of harmful algal blooms. However, field trials and longer duration experiments are required to provide further evidence for the use of acoustics as a monitoring tool in the natural environment where several factors may interfere with valve behaviours.