Ecophys.Fish: A Simulation Model of Fish Growth in Time-Varying Environmental Regimes

Ecophys.Fish is a model for simulating rates of fish growth in environmental regimes that have simultaneous temporal variation in food, oxygen, temperature, pH, and conductivity/salinity. The purpose of this presentation is to introduce Ecophys.Fish to those who might want to use it as a framework or starting point for applications of their own. Our model incorporates a quantitatively explicit statement of concepts originally formalized by F.E.J. Fry (Fry 1947, 1971) and subsequently elaborated by Neill and Bryan (1991), among others. Fry's "physiological classification of environment" and "metabolic scope " concept were coupled with conventional bioenergetics to 97 provide the model's theoretical basis. Jointly, the factors of environment determine the animal's metabolic scope, which is the difference between its active (= maximum aerobic) and standard ( = obligatory minimum) metabolic rates; metabolic scope is the animal's capacity to perform useful activities like locomotion, feeding, and the physiological processing of food that leads to growth.