Most studies on feeding-related activities of fish in cold water (0" C) have not used eurythermal species or examined a broad suite of activities. In this study we report on the feeding, growth, behaviour and conversion-efficiency o f O t Atlantic cod in response to water temperature and food availability. In one experiment. activity, opercular beat and growth decreased with decreasing temperature over the range 8 . 3 4 6 " C. However, the conversion efficiency increased with decreasing temperature, a result partly explained by the relative change in activity and opercular rate. In another experiment, temperature had a linear effect on growth in cod fed different food rations. Both food availability and temperature were found to influence growth in groupO+ cod. The specific growth rate of cod in this experiment exceeded 2% day-'. Growth data collected from cod sampled in the field during the cold-water period showed a progressive increase of mean length over the season. Overall, these results demonstrate that O + cod have adapted to life in cold-water environments, in contrast to adult cod which mostly inhabit warmer environments.

The aquaculture of marine finfish in Newfoundland presents a challenge due to the cold-water (

The production of viable larvae is critical to any aquaculture venture. Since lipids are important components of fish eggs, the amount and nature of the lipid may be crucial to the survival of the larvae. In this study the lipid content of unfertilized eggs from first‐time and repeat spawning Atlantic halibut females was compared. The egg lipid content for the first‐time spawner ranged from 0·18 to 0·41mg/egg; the range for the repeat spawner was 0·27 to 0·38mg/egg. However, the mean total lipid per egg values were similar for both fish at ca. 0·31mg/egg. The repeat spawner prodticed more eggs than the first‐time spawner, thus allocating more lipid to egg production. In the eggs from the two fish 62–84% of the lipids was phospholipid.