Age of Atlantic halibut larvae (Hippoglossus hippoglossus L.) at first feeding

Abstract

Halibut larvae at different age (150 to 315 day-degrees) were transferred to outdoor startfeeding tanks each with two internal plastic bags (100 litre). The larvae were fed wild zooplankton. One bag was sampled after 24 hours, and the other after nine days. Numbers of larvae with food in the gut, without food in gut and dead larvae, were counted for each larval age tested. The results showed that some larvae captured prey at an age of 150 day-degrees. However, at this age few larvae were alive after nine days. The fraction of larvae with food in the gut increased during the period tested. Survival after 24 hours and after nine days were highest when first feeding took place at a larval age of approximately 230 day-degrees.