The Entangled Bank Laboratory is pleased to announce the publication of our latest work "Designing the Next Generation of Condition Tracking and Early Warning Systems for Shellfish Aquaculture" in collaboration with Gravity Marine Consulting. With this article, we have now completed our first cycle of three studies on valvometry measurements, data analysis and modelling.
Valvometry is a simple, non-invasive technique that measures the gape (or opening) distance between the two shells of a bivalve. More than a century ago, it was already suggested that patterns in the opening distance would provide information about the physiological state and health of a bivalve (Marceau 1905; 1909). By the 1990s, as sensor and recording systems migrated from analogue to digital methods, valvometry had become a viable technique for water quality monitoring. Several different systems have been tested and commercialised (e.g. MosselMonitor or the recent testing of another system by Total Energies).
Why hasn’t valvometry been widely adopted on shellfish farms for stock monitoring?
Globally, the value of shellfish is estimated at around 17 billion euros (in 2018 USD). French shellfish farms sell more than half a billion euros annually of products (2017 data, France AgriMer 2020).
The ability to track the condition of stocks in real-time has been a shared goal of both producers and regulatory agencies (Andrewartha et al. 2015). Until now, a major drawback of valvometry has been that the valve movement patterns are not interpreted in terms of a biological process, but in the relative terms of statistical probabilities. This may explain why valvometry has not yet penetrated the shellfish farming industry, despite the stock's high economic value.
This is why we developed an eco-physiological model based on the biophysics of the bivalve adductor muscle system that exploits valvometric data series. We have expanded our new model framework for valvometry (Guarini et al. 2020) to include the analysis and diagnosis of the dynamics of valve gaping patterns measured in real-time and under varying environmental conditions. This new model adds the power of mechanistic hybrid dynamic modelling to existing statistical approaches.
Article citation and journal link
Guarini, J.-M.; Hinz, S.; Coston-Guarini, J. Designing the Next Generation of Condition Tracking and Early Warning Systems for Shellfish Aquaculture. J. Mar. Sci. Eng. 2021, 9, 1084. doi: 10.3390/jmse9101084.
Sources cited
Andrewartha, S., Elliott, N., McCulloch, J. and P. Frappell. 2015. Aquaculture sentinels: Smart-farming with biosensor equipped stock. Journal of Aquaculture, 7(1):1000393.
Guarini, J.M., Coston-Guarini, J. and Comeau, L.A. [2020 preprint] Interactions between discrete events and continuous dynamics in the regulation of scallops valve opening: insights from a biophysical model. bioRxiv 2020.12.25.424408. doi: 10.1101/2020.12.25.424408
Marceau, F. 1905. Recherches sur la physiologie et en particulier sur les lois de la production de travail mécanique par les muscle adducteurs des acéphales. Bulletin de la Station Biologique d’Arcachon, Travaux des Laboratoires, Huitième Année, pages 41–47 .
Marceau, F. 1909. Recherche sur la morphologie, et l’histologie, et la physiologie comparées des muscles adducteurs des mollusques acéphales. Archives de Zoologie Expérimentale et Générale, Série 5, 2: 295– 469.