Marine Biology 146: 733-738

 

Effect of temperature on specific dynamic action in the common octopus, Octopus vulgaris (Cephalopoda) 

Stelios Katsanevakisa, Nikos Protopapasa, Helen Milioub and George Verriopoulosa

 a Department of Zoology-Marine Biology, School of Biology, National and Kapodistrian University of Athens, Panepistimioupolis, 15784 Athens, Greece 

b Laboratory of Applied Hydrobiology, Department of Animal Production, Agricultural University of Athens, Iera Odos 75, 11855 Athens, Greece

Abstract

Feeding causes an increase of metabolic rate, which initially escalates rapidly, reaches a peak value and then gradually declines to the pre-feeding rate. This phenomenon, termed ‘specific dynamic action’ (SDA), reflects the energy requirements of the behavioral, physiological and biochemical processes that constitute feeding. The effect of temperature on SDA of the common octopus, Octopus vulgaris, was evaluated, by measuring the temporal pattern of oxygen consumption rates of octopuses, after feeding, at two constant temperatures, 20oC and 28oC. At 20oC, the relative increase in the oxygen consumption rate after feeding (relative SDA) was significantly greater than at 28oC. The peak relative SDA occurred 1hr after feeding and it was 64% at 20oC and 42% at 28oC. However, SDA absolute peak, SDA duration (9.5h) and SDA magnitude (the integrated postprandial increase in oxygen uptake) did not differ significantly between the two temperatures, indicating that the energetic cost of feeding was the same at both temperatures. The SDA response in O. vulgaris was much faster than that of polar species, which have extended SDA responses due to low temperatures and was also relatively fast in relation to that of other temperate species, which is probably connected to the remarkably high growth rates of the species. A possible explanation of the observed summer migration of large octopuses from shallow to deeper areas is given, based on the effect of temperature on the energetic requirements of octopuses.