Dynamics in a Salmon Culture Pond

Abstract

This simulation study of a salmon culture pond at Arcata, California investigated the dynamic interrelationships within the ecosystem of fingerling coho salmon, a small crustacean (an amphipod) that served as the salmon's principal food, the amphipod's food, and the tem perature and salinity of the water in the pond. The simu lations showed that the optimum salinity for maximum growth was 23.5 parts per thousand, and that deviation from this optimum decreases the growth rate of amphipods, which means that more of them are eaten by the fish, because the amphipods are of edible size for a longer time. Competition among the amphipods was great when the density of their food was low. The simulations developed an understanding of the mechanisms at work in the pond ecosystem and resulted in information on which to base suggestions for improved strategies for managing the pond.