Grant: Discovery Grants Program - Ship Time

Capelin, a small minnow-like fish, is the focal forage fish species that preys on many invertebrates and is in turn preyed on by most large predators, including cod, seals, whales and birds in the Northwest Atlantic. Capelin provide essential linkages for energy transfer among trophic levels and, thus, are often thought to mediate ecosystem-level changes. In previously NSERC-funded expeditions, we discovered capelin spawning in deep water (demersal) in coastal Newfoundland, where this species is primarily thought to spawn on beaches. Large aggregations of capelin form at these spawning sites, causing predators to concentrate. This results in areas where high abundances of organisms gather, often referred to as 'biological hotspots'. Our research aims to determine whether capelin select between beach and demersal spawning habitat on the basis of current environmental conditions or whether capelin are obligate beach and demersal spawners. We also examine the time and energetic consequences of foraging within hotspots by top predators. To do this, we employ a novel assemblage of sophisticated marine electronic equipment aboard ships combined with genetic and stable isotope analytical techniques, as well as predator diets and telemetry-based foraging activities. Our research involves collaborative efforts between university researchers and commercial fishers, which has and will continue to make major advancements in our understanding of capelin ecology and how it influences top predators. Ultimately, this research will increase the accuracy of capelin stock assessment indices and promote novel, incisive fisheries management approaches to avoid ecological and socioeconomic catastrophes that have occurred in our coastal waters and communities around the globe.