Krill are a major food source for adult fish, seals, whales and birds. After Copepods , they are the most important Zooplankton group in the world oceans. Larval and immature fish feed on the smaller juvenile euphausiids. Krill live in the dark, at 100 metres or more by day.
Many adults migrate diurnally to the surface at night, to feed on the phytoplankton.
Most are herbivorous, but some are omnivorous feeders. Two species most likely to be found in Georgia Strait, San Juan Archipelago, and Puget Sound, are Euphausia pacifica and Thysanoessa rachii . Off the West coast of Vancouver Island the most common are Euphausia pacifica and Thysanoessa spinifera . More information on krill and how they are measured .