Forage Fish Ecology
The lab focuses on the ecology of the focal forage fish species in the northwest Atlantic, capelin (Mallotus villosus). Capelin is the primary prey for most top predators in coastal Newfoundland during the summer, including predatory fish, marine birds and mammals. Since 2000, the lab has discovered and described deep-water (demersal) spawning sites of capelin on the exposed northeast Newfoundland coast, where this species was considered to primarily spawn on beaches. We integrate capelin tagging and sampling with long-term monitoring of spawning sites (i.e. site use, timing, and oceanographic conditions) to examine how capelin select spawning habitat. In addition, we investigate what otolith microchemistry can tell us about the ecology of capelin, including habitat- and region-specific productivity, connectivity and natal origin. Due to increasing abundance of capelin (typically considered a sub-Arctic species) into Arctic regions, we are also conducting research on capelin ecology in the eastern and western Canadian Arctic.
Research
Predator Ecology
The lab has found that annually persistent deep-water spawning sites of capelin result in the formation of biological hotspots, where high abundances of marine birds, whales and predatory fish aggregate. We integrate ship-based surveys, with at-sea experiments and underwater video of foraging behaviour of predators at deep-water spawning sites of capelin to examine the influence of these persistent prey aggregations on predator foraging behaviour. We also combine animal-borne activity loggers, tracking devices and dietary metrics (stable isotopes, fatty acids, stomach contents) with hydroacoustic estimates of capelin (prey) density and behaviour to investigate how the foraging behaviour of seabirds and whales changes under varying prey density. We are now shifting to examine food web interactions within a long-term, multi-species context.