Finding the predators of Arctic fish eggs and larvae

Description

Predators on Arctic fish eggs and larve has not been investigated but could come from zooplankton taxa such as jellyfishes, chaetognaths, amphipods, and carnivorous copepods. Identifying larval fish in predator stomachs is difficult because of rapid digestion but novel methods based on whole-body metabarcoding are promising. The project will use ethanol-preserved zooplankton samples from different Arctic locations to study the diet of potential predators of ichthyoplankton such as copepod Paraeuchaeta glacialis, chaetognath Sagitta elegans, and amphipod Themisto libellula, using different genetic approach such as whole-body DNA extracts and deep, brute force metabarcoding of an 18S rDNA fragment. The results will be combined with abundance data of predators, fish eggs, larvae, and other potential prey obtained from taxonomical analyses to quantify the relative of different zooplankton predators on Arctic ichthyoplankton mortality.