Diet and metabolic rate in the supralittoral isopod Ligia Pallasii: the effect on oxygen uptake of ration levels of natural and chemical diets

Abstract

1. 1. The effect of ration-level on rate of oxygen consumption in the rock louse Ligia pallasii was studied using natural diets of seaweeds and artificial diets of chemicals. 2. 2. No significant effect on oxygen consumption was shown in animals on a 50% ration of either seaweeds or chemicals. 3. 3. A 10% ration caused a significant decrease in oxygen uptake in Ligia over 35 days of study, from 24.6 to 11.9 μ1 indiv −1 hr −1 for animals on a seaweed diet, and from 24.3 to 15.9 μ1 indiv −1 hr −1 for animals on a chemical diet. 4. 4. A comparison of energy costs of respiration with incoming food energy at each ration level showed that some growth was theoretically possible in Ligia even on a 10% ration of seaweeds.