Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
4550028 | Journal of Sea Research | 2011 | 9 Pages |
Many studies based on bioenergetics growth models have investigated the effects of environmental factors on oyster (Crassostrea gigas) growth and physiology. However, most of these models are site-specific and cannot be applied to other culture sites without the re-estimation of parameters or re-formulation of some processes. We aimed to develop a generic growth model suitable for application in contrasting environments, with a constant set of parameters. We tested the oyster-DEB model (Bourlès et al. 2009) for the stimulation of C. gigas growth in different cohorts (spats and adults) at major shellfish culture sites in France, in several years: Arcachon (1993–1994); Marennes-Oléron (2007); Quiberon (1999, 2000, 2001); Brest Harbour (2008); Mont-Saint-Michel Bay (2003); Baie-des-Veys (2002). These different ecosystems offer a wide range of values for the two forcing variables of the model: water temperature (range: 6-24 °C) and phytoplankton concentration (annual average: 110–700 × 103 cell L-1). The validation data (dry flesh mass of C. gigas) were obtained from various growth surveys carried out by IFREMER. The oyster-DEB model simulated the oyster growth dynamics of both spat and adult stages of C. gigas accurately over time at the various culture sites. The model captures: i) the active spring growth; ii) the timing and amplitude of spawning events; and iii) the lean periods (i.e. loss of dry flesh mass) in autumn and winter. The half-saturation coefficient Xk is the only model parameter that varied between sites and years. This environment-specific coefficient reflects variability in the food of the oysters: quantitative and qualitative effects of the inorganic material and of the phytoplankton species on the feeding response of C. gigas. With a single set of parameters (other than for Xk), this is thus the first bio-energetic growth model for C. gigas robust enough and of a sufficiently generic nature for the accurate simulation of oyster growth in different Atlantic ecosystems.
► We test a generic growth model of Crassostrea gigas in several Atlantic environments. ► It simulates the growth of oyster spat and adults accurately over time at many sites. ► It captures spring growth, timing and amplitude of spawning events, loss of dry mass. ► XK is the only parameter that varies (sites, years) and reflects food variability.