The effects of temperature on growth rate and growth efficiency of juvenile common wolffish

The effects of temperature on the survival, growth rate and growth efficiency of larval and juvenile common wolffish, Anarhichas lupus L. were studied at 0-31 days and 9-12 months post-hatching, respectively. The influence of temperature regime during egg incubation on subsequent survival and growth was also examined. The fish were reared at constant water temperatures of 5, 8, 11 and 14 degrees C, and all groups were fed dry pellets. At age 1 month, maximum growth rates were observed at 11 and 14 degrees C. Growth rates and survival of early juveniles were dependent upon incubation history, high growth being obtained only if rearing temperature exceeded the temperature of egg incubation. In juveniles at age 9-12 months, the relationships between temperature and growth, and temperature and growth efficiency were parabolic: the optimum water temperatures for growth (T-opt.G) and growth efficiency (T-opt.GE) were 11 degrees C and 9.7 degrees C respectively. The growth rate and growth efficiency at these water temperatures were 0.9% day(-1) and 0.45 g weight gain per g food offered, respectively.