Physiology of Finfish and Shellfish (2+1)

4.1.8. Species Effects

At any given level of temperature, oxygen and activity, two different species may have different metabolic rates. For example, a carp and a trout have different hemoglobin oxygen dissociation curves and different tissue tolerances for hypoxia. This allows the carp to tolerate lower DO conditions without going into oxygen debt (lower critical point) and trout to sustain a higher rate of activity (higher critical point). It is an evolutionary trade off that adapts species to different habitats and behaviors.