%0 Journal Article %J Ecosystems %D 2009 %T A Box Model for Ecosystem-Level Management of Mussel Culture Carrying Capacity in a Coastal Bay %A Ramon Filgueira %A Jon Grant %X

The carrying capacity of shellfish aquaculture is determined by the interaction of cultured species with the ecosystem, particularly food availability to suspension feeders. A multiple box dynamic ecosystem model was constructed to examine the carrying capacity for mussel (Mytilus edulis) aquaculture in Tracadie Bay, Prince of Edward Island, Canada. Criteria for carrying capacity were based on chlorophyll concentration. The model was run in two different years (1998 and 1999) in which time series for three points inside the bay and a point outside the bay were available. This data set allows spatial validation of the ecosystem model and assessment of its sensitivity to changes in boundary conditions. The model validation process indicated that the differential equations and parameters used in the simulation provided robust prediction of the ecological dynamics within the bay. Results verified that mussel biomass exerts top-down control of phytoplankton populations.

%B Ecosystems %R 10.1007/s10021-009-9289-6 %0 Journal Article %J Ecological Modelling, %D 2007 %T A box model of carrying capacity for suspended mussel aquaculture in Lagune de la Grande-Entrée, Iles-de-la-Madeleine, Québec %A Jon Grant %A Kristian J. Curran %A Thomas L. Guyondet %A Guglielmo Tita %A Cédric Bacher %A Vladimir Koutitonsky %A Michael Dowd %K Aquaculture %K Carrying-capacity %K Ecosystem model %K Magdalen Islands %K Mussels %X

An object-oriented model of environment–mussel aquaculture interactions and mussel carrying-capacity within Lagune de la Grande-Entrée (GEL), Iles-de-la-Madeleine, Québec, was constructed to assist in development of sustainable mussel culture in this region. A multiple box ecosystem model for GEL tied to the output of a hydrodynamic model was constructed using Simile software, which has inherent ability to represent spatial elements and specify water exchange between modelled regions. Mussel growth and other field data were used for model validation. Plackett–Burman sensitivity analysis demonstrated that a variety of bioenergetic parameters of zooplankton and phytoplankton submodels were important in model outcomes. Model results demonstrated that mussel aquaculture can be further developed throughout the lagoon. At present culture densities, phytoplankton depletion is minimal, and there is little food limitation of mussel growth. Results indicated that increased stocking density of mussels in the existing farm will lead to decreased mass per individual mussel. Depending on the location of new farm emplacement within the lagoon, implementation of new aquaculture sites either reduced mussel growth in the existing farm due to depletion of phytoplankton, or exhibited minimum negative impact on the existing farm. With development throughout GEL, an excess of phytoplankton was observed during the year in all modelled regions, even at stocking densities as high as 20 mussels m−3. Although mussels cultured at this density do not substantially impact the ecosystem, their growth is controlled by the flux of phytoplankton food and abundance of zooplankton competitors. This model provides an effective tool to examine expansion of shellfish farming to new areas, balancing culture location and density.

%B Ecological Modelling, %V 200 %P 193-206 %8 1/2007 %N 1-2 %R doi:10.1016/j.ecolmodel.2006.07.026