This document describes the formulation, construction, performance, and evaluation of a computer model designed to simulate energy flow in the cultured blue mussel, Mytilus edulis. The model was developed in the belief that it would be useful in addressing a number of problems and questions associated with the commercial cultivation of this species, particularly those related to site selection and carrying capacity.

Construction of the model involved synthesizing current ideas and hypotheses on the major biophysical factors thought to control the growth, spawning and mortality of Mytilus, and expressing this information mathematically in a form that could be solved over time with the aid of a computer. Inputs to the model include water temperature and particulate inorganic and organic matter concentration. The model outputs shell and meat growth rates, condition indices, biofeces production, spawn production and spawning times. Validation of the model against several independent data sets suggests the model has significant predictive capability and can provide a useful framework for investigating problems such as site selection, summer mortality, carrying capacity and the environmental impact of mussel culture.

The report is divided into three main sections. The first documents the formulation of the model in terms of the theoretical background upon which it is based and the data base available for its construction. The second section describes the model's behavior in general, presents the results of a sensitivity analysis, and compares output of the model with data obtained from field studies. The final section discusses the model in terms of its potential and limitations in addressing some of the problems associated with shellfish culture.