My research program focuses on investigating the biology and behaviour of important forage fish species in marine ecosystems and how this shapes the biology of top predators, primarily marine birds and whales. Forage species lie at the core of complex marine food webs, providing essential linkages among trophic levels. Investigations at regional scales often reveal areas where high abundances of organisms persistently overlap during certain periods of the year, referred to as ‘biological hotspots’. There are many examples where the formation of these hotspots is driven by high-density aggregations of forage fish. Owing to the concentration of predator-prey interactions at hotspots, energy flow through marine food webs, a key ecosystem process, is maximized within these areas. This research will increase our ability to maintain the long-term productivity of northern marine ecosystems to sustain fisheries yields and conserve marine biodiversity.