Scope for Growth as Function of Temperature, Salinity and Body Weight in Tivela stultorum (Mollusca, Lamellibranchia)

Abstract

Scope-for-growth is an integrative measure of physiological processes occurring in the organism and, as such, provides information on organism-environment functional interactions. The physiological responses necessary to calculate the scope for growth were measured in different salinity-temperature combinations in adult Pismo clam, Tivela stultorum, of different sizes. Parallel box plot and multiple regression equation, represented by surface responses, show that the Pismo clam has a positive scope-for-growth in all salinity-temperature combinations. However, a greater energy portion for both somatic growth and reproduction was obtained at 110% sea water at 21°C and in smaller sizes. This knowledge is useful in cultural practices aimed at obtaining clam "seeds" under laboratory conditions so as to restock naturally occurring banks.