Physiological Indices of Stress in Mytilus Edulis

Abstract

In nature, organisms are subjected to a variety of environmental factors acting together and they respond to the total resulting stimulus rather than to single environmental variables. In addition, the animal's response is not in terms of individual physiological rates but rather as a whole organism. Therefore an experimental approach to an animal's response to a complex environment could usefully include (a) multivariate experiments and (b) integration of individual physiological processes to provide a greater under-standing of the ‘whole organism’ response. In this paper, non-linear multiple regression equations and response surfaces are used to describe and illustrate the combined effects on the common mussel, Mytilus edulis L., of body size, ration and season on physio-logical integrations such as the scope for growth, growth efficiency and the oxygen: nitrogen ratio (reviewed by Bayne, 1975; Bayne, Widdows & Thompson, 1976). The data used to compute these physiological integrations are derived from a series of multivariate experiments described in a preceding paper (Widdows, 1978).