1. To describe the ontogeny of foraging behaviour of halibut larvae, and to determine any detrimental effects of current commercial rearing practices in terms of structural damage, developmental abnormalities and behavioural competence 2. To investigate the resistance of larvae to handling in relation to developmental stage, in order to determine the most appropriate stage for handling and to devise non-damaging handling methods 3. To investigate whether larvae exhibit temperature, or salinity preferences at critical developmental stages, by means of behavioural observations in temperature/salinity gradients and by subjecting larvae to different acclimation regiemes in rearing tanks 4. To develop husbandry protocols that reduce the incidence of surface aggregation and that enable larvae to be retained in UK upwelling tanks for the optimal duration, in terms of handling resistance, behavioural competence and feed initiation success 5. To determine the optimum conditions for transferring larvae to first feeding tanks, by investigating responses to physical, chemical and biological parameters, including mechanisms by which microalgae 'green water' promote or enhance feed ingestion 6. To obtain a reproducible benefical microbial flora during the early stages of larval rearing, with the aim of establishing an industry -relevant probiotic approach at the feed initiation stage