Growth of the Pacific oyster (Crassostrea gigas) in a high-turbidity environment: Comparison of model simulations based on scope for growth and dynamic energy budgets

Abstract

We compared growth simulations by dynamic energy budget (DEB) and scope for growth (SFG) models of the Pacific oyster Crassostrea gigas, cultivated in Bourgneuf Bay on the French Atlantic coast. This bay is located at a latitude in the middle of the European range of the species, and is characterized by high concentrations of suspended particulate matter (SPM) and a marked gradient between high-turbidity sites in the north (daily SPM > 500 mg L -1 ) and intermediate-turbidity sites in the south. The models use two forcing variables: seawater temperature and food density. We tested two indices of food availability: chlorophyll a and microalgal concentrations. In the SFG model, food intake is simulated by a type-II Holling functional response, as in the DEB formulation, and the effect of turbidity in both models is therefore taken into account principally through the half-saturation coefficient for this functional response. Chlorophyll a concentrations were three to four times higher at the high-turbidity site, but oyster growth rates were significantly lower at this site than at the intermediate-turbidity site. A comparison of observed and simulated values showed that the DEB model performed better than the SFG model if microalgal concentration was used as an index of food availability, with the SFG model underestimating oyster growth in summer and autumn. However, the SFG model was much more efficient if chlorophyll a concentrations were used, with the DEB model systematically overestimating summer and autumn growth. This comparison suggests that both SFG and DEB simulations could be improved, to give a more accurate description of oyster growth in a turbid environment, and that the pre-ingestive selection mechanisms used by suspension feeders in turbid environments should probably be included in the formulation of feeding processes.Highlights ► The growth of Pacific oyster was studied in a high-turbidity ecosystem. ► At the highest turbidity site, the growth was lower compared to an intermediate turbidity site, in spite of a high availability of food resources. ► Growth was simulated by two models (Scope For Growth vs. Dynamic Energy Budget) showing different simulations according to the food quantifier tested (chlorophyll a vs. cell concentration). ► Both models could be improved by including pre-ingestive feeding responses, playing a significant role for suspension-feeders inhabiting turbid environments.

Numerical modelling of spatio-temporal variability of growth of Mytilus edulis (L.) and influence of its cultivation on ecosystem functioning

“…Handå et al, 2011;Filgueira et al, 2011;Maar et al, 2009;Rosland et al, 2009Rosland et al, , 2011Saraiva et al, 2011a;Thomas et al, 2011;van der Veer et al, 2006), Crassostrea gigas (e.g. Alunno-Bruscia et al, 2011;Barillé et al, 2011;Bernard et al, 2011;Bourlès et al, 2009;Emmery et al, 2011), and other species. Several authors have dynamically coupled DEB models with biogeochemical models to provide feedbacks from aquaculture farms to phytoplankton and nutrient dynamics.…”

Performance measures and models for open‐water integrated multi‐trophic aquaculture

“…; Barillé et al . ). The assimilation efficiency κ A is the ratio of assimilated energy A , to ingested energy X , and this is analogous to absorption efficiency in bioenergetic approaches.…”

“…This point is demonstrated by the Barillé et al . () study comparing SFG and DEB approaches for growth modelling of the Pacific oyster ( C. gigas ) in a high‐turbidity environment. The SFG model was more effective if chlorophyll a concentrations were used, while the DEB model systematically overestimated summer and autumn growth, suggesting that both SFG and DEB simulations could be improved upon.…”

“…Diet density is represented as a functional response based on Holling's type II functional response curve (Holling, 1959) with a half saturation coefficient (k X ). Temperature affects enzyme functionality associated with all rates according to the Arrhenius law (Pouvreau et al 2006;Barill e et al 2011). The assimilation efficiency j A is the ratio of assimilated energy _ P A , to ingested energy _ P X , and this is analogous to absorption efficiency in bioenergetic approaches.…”

Stochastic Modeling of Forces on Jacket-Type Offshore Structures Colonized by Marine Growth

“…This biological model was calibrated by a site with similar environmental characteristics and for the same species of mussels. Different bioenergetics models have been developed to model the growth of bivalves depending on the environmental conditions, and among them, Dynamic Energy Budget (DEB) models [13] have been successfully applied to several bivalve species [24,[35][36][37][38]. DEB models do not use empirical allometric relationships, but simply state that feeding is proportional to surface area, whereas maintenance is scaled according to structural body volume [13].…”