Seasonal temperature regulates network connectivity of salmon louse

Abstract Chronically high infestation of salmon louse (Lepeophtheirus salmonis) questions the sustainability Norwegian Atlantic (Salmo salar) aquaculture industry. The confinement millions hosts, within hundreds farms with overlapping larval dispersal kernels create structure for extremely persistent parasite meta-populations. However, processes regulating temporal variation in cross-contamination pelagic stages among (i.e. connectivity), a vital process driving population dynamics, are not well described. Here, we employ data driven biophysical model that reproduces three-and-a-half years production histories 132 western Norway and quantifies connectivity infective lice ocean currents. We show although complex geography fjords governs long-term topology network, there was strong seasonal component to network fragmentation. main de-structuring agent delayed infectivity at cooler temperatures increasing distances, enhanced by occasional large scale wind forcing events. Coordinated fallowing strategies de-lousing treatments only played marginal role fragmentation, suggesting novel restraining consider environmentally sensitive transport distances must be developed successfully break up network.