Growth and food intake of Octopus tetricus (Mollusca : Cephalopoda) in aquaria

Abstract

The growth and food intake of 14 octopuses fed to excess on live crabs was followed over periods of 2-30 weeks. Five octopuses were later changed to a less-than-excess food supply and four additional octopuses were kept on a less-than-excess food supply from the commencement of observations. The majority of octopuses with excess food supply showed rapid, positive growth in weight but old males and a brooding female showed weight loss. The growth prior to senescence or egg-laying was used to determine a general equation for growth in weight of octopuses fed to excess. The daily feeding rate of octopuses with excess food supply was found to be a function of weight and temperature. There was an approximately linear relationship between growth of octopuses on the excess and less-than-excess food supplies and daily feeding rate but there was no significant relationship between growth and temperature in the temperature range experienced (16.5-24.2ºC). Variation in the maintenance requirement and the efficiency of food conversion were considered to be responsible for the lack of relationship between growth and temperature.