Krill live in all the oceans of the world, the most abundant of which is Antarctic krill. This species, found in the Southern Ocean, has an accumulated weight of between 125 million to 6 billion tons.
There are 85 species of krill. One of these, Euphausia superba, lives only in the Antarctic Ocean, and Pacific krill are found in the Pacific Ocean. The Bentheuphausia ampblyops are deep water krill and live at depths of more than 3,000 feet.
Krill are tiny, 2-inch crustaceans that are a pinkish color and look vaguely like shrimp. They have exoskeletons and multiple legs. They travel in swarms, turning the ocean pink with their sheer numbers. These animals are a critical component of the food chain. According to National Geographic, krill are the fuel of the ocean. Their main source of food is phytoplankton. They are then the main source of food for numerous fish, birds, animals and whales.
Krill have a lifespan ranging from six to 10 years. Antarctic krill reproduce at the beginning of the year. Each female lays nearly 10,000 eggs multiple times. The krill eggs sink to depths of 10,000 feet before hatching. Krill feed mostly on phytoplankton, though occasionally they eat algae or even other krill.