Combined effects of temperature and density on the growth and survival of juveniles of the Australian freshwater crayfish, Cherax destructor Clark, part 1

A 31 day growth trial of newly independent (stage 3) yabbies (Cherax destructor) was conducted using three density levels, 4, 8 and 16 per 2.5 l aquarium, equivalent to 150, 300 and 600 m -2 , and three temperatures (22, 25 and 28°C). Average final weight of yabbies was found to decline with increasing density, and to increase with increasing temperature. A significant interaction was found between density and temperature with the effects of temperature being reduced at higher densities. Analysis using yield produced similar results with the optimal combination of temperature and density found to be 25°C and 600 m -2 . Survival was not affected by density, but declined with increasing temperature. The implications of these findings for optimal conditions for the intensive culture of juvenile yabbies are discussed.