Alexandre Le Moal 1, 2
1Alfred Wegener Institute, Germany - 2Carl von Ossietzky University of Oldenburg, Germany
The European native oyster (Ostrea edulis) is an endangered species of coastal ecosystems and a key organism in the restoration of biogenic reef habitats. Since a few years, conservation and active restoration of European oyster reefs is a major focus of ecological restoration efforts to take advantage of the wide-ranging ecosystem functions and services this species and it reefs provide (e.g. substrate formation and biodiversity enhancement).
Despite these recent efforts, the knowledge on the general physiology of Ostrea edulis is rudimentary. Notably, studies on chronobiological aspects, such as the timing-keeping of their behavioral and physiological traits are still missing, which is pivotal to understand their ability to adapt and fit with their cyclic and fluctuating environment.
Thus, an objective of my PhD project is to investigate the resilience of Ostrea edulis on Helgoland (Germany), by studying the impact of geophysical and environmental cycles (daily, tidal, lunar and annual cycles) on important life-cycle traits like valve behavior, which is directly involved in physiological processes in bivalves.
To investigate Ostrea edulis biological rhythms, their valve behavior will be monitored continuously during 16 months in the field at Helgoland, using a High Frequency Non-Invasive (HFNI) valvometer biosensor. This research will investigate the existence of daily, tidal, lunar or seasonal rhythmicity in their valve behavior and show how the valve activity is impacted by environmental parameters (temperature, turbidity, chlorophyll a etc. measured in parallel) or by new anthropic pressure as underwater noise pollution.
We hope that our findings may contribute to better understand how natural environmental cycles might affect the behavioral rhythms of this endangered species and elucidate their functioning and their resilience in the actual changing environment to improve our restoration efforts.
Biography
After a Bachelor’s degree in general biology and ecology at the University of South Brittany (France), Alexandre Le Moal has completed his master’s degree of marine science at the University of Bordeaux (France). He has made his two master’s internships at the Arcachon marine station (France) during which he discovered the chronobiology with D.Tran and L.Payton. Then, he continued in this field during his PhD at the Alfred Wegener institute (Germany) with B.Meyer to study the biological rhythms of Ostrea edulis.