Northern Krill

Meganyctiphanes norvegica

The northern krill (Meganyctiphanes norvegica) is the largest and most abundant euphausiid crustacean in the North Atlantic. Adults reach 3-4 cm in length and display a translucent pinkish body with darker compound eyes and prominent antennae. They are capable of bioluminescence, producing blue-green light from specialized photophores on the underside of their body, likely for communication and counter-illumination camouflage. They form dense swarms of millions of individuals in the water column at depths of 0-400 meters, undertaking daily vertical migrations — ascending to surface waters at night to feed on phytoplankton and descending to deeper waters during the day. They are a keystone species in North Atlantic ecosystems, serving as the primary food source for baleen whales, many fish species, and seabirds. Divers occasionally encounter dense krill swarms on night dives, where their bioluminescent displays create magical underwater light shows.