Workpackage 5: Verification of abiotic and biotic conditions at pilot scale will be performed on different sites.

The importance of genotypic variability/clonal selection in adaptability or instability of rotifer cultures will be verified on pilot scale. Strains derived from Mediterranean hatcheries will be grown under local conditions in Belgium (rotifer production system optimised for temperate and tropical predator species) and Norway (rotifer culture technology for cold water marine fish species). Additionally, strains currently used in Norway and Belgium will also be interchanged. In addition, two different culture techniques will be applied: both partners will use a batch and a high-density recirculation system (Suantika et al., 2000). In comparison, the different culture conditions and systems will also be applied to a mixture of selected clones with high genotypic variability (cfr. WP1).
Growth performance, as well as genetic drift in the different rotifer strains will be followed during culture. This will allow estimating to what extent adaptation to common culture conditions and methods in local hatcheries has resulted in narrow-niched specialists, with low adaptation potential to changing environmental conditions .