Krill is a small, shrimp-like crustacean that inhabits ocean waters. These small creatures are near the bottom of the food chain, providing nutrients for a variety of animals. Krill exhibit what is known as daily vertical migration, which means they move toward the surface of the water at night and move deeper into the ocean during the day. This behavior allows predators at the surface and in the deep to have access to the krill at some point during the day. This article details various animals that eat krill for food.
9 Animals That Eat Krill
1. Blue Whale
Scientific name: Balaenoptera musculus
Blue whales are the largest animals on Earth, measuring up to 105 feet long and weighing up to 200 tons. These large carnivorous mammals rely almost exclusively on a diet of krill, eating up to four tons of krill each day.
Blue whales are a species of baleen whale, which means instead of teeth, they have fringed plates (called baleen) growing from the upper jaw. They take in large amounts of water and use the baleen to filter out the krill as they push out the water with their tongues.
2. Humpback Whale
Scientific name: Megaptera novaeangliae
Another member of the baleen whale family is the humpback whale. This species can be found in every ocean worldwide and travels great distances during migration, with some groups, or pods, traveling up to 5000 miles. Their main food source is krill, and they use their baleen to filter between 4400 and 5500 pounds of krill each day.
Scientific name: Spheniscidae
Penguins are flightless, aquatic animals. They are members of the Spheniscidae family, which includes 18 different penguin species. Almost all of these species are located below the equator in cold climates.
They hunt for food in the ocean, and a penguin’s diet largely consists of krill. Penguins are extremely good swimmers, reaching speeds of up to 15 miles per hour, and scooping up to 25 grams of krill per minute.
4. Whale Shark
Scientific name: Rhincodon typus
The whale shark is the largest species of fish on Earth, growing up to almost 62 feet long. These large creatures move slowly through the water and use filter feeding to catch large amounts of krill.
Filter feeding is the process of moving through the water with the mouth open, moving the head back and forth to allow food to flow into the mouth. Whale sharks are unique in the fact that their mouth serves as a vacuum, sucking the water and food into the mouth to filter out the krill and other food.
5. Crabeater Seal
Scientific name: Lobodon carcinophaga
There are more crabeater seals in the world than all other seal species combined. They primarily live in Arctic climates and can easily travel over ice faster than a person runs.
Some crabeater seals travel to other regions such as Australia, New Zealand, South Africa, and South America. Despite the name, this seal’s diet consists mainly of krill. In fact, krill make up around 90% of their diet.
Scientific name: Channichthyidae
This cold-blooded creature lives in the cold waters surrounding Antarctica. Often called the white crocodile fish, the icefish has a mouth full of teeth like a crocodile.
These fish have clear blood because their blood doesn’t contain hemoglobin. Their diet consists of small fish, plankton, and large amounts of krill. Since krill is abundant in the harsh waters of Antarctica, the icefish rely on it as their main food source.
7. Sea Lions
Scientific name: Otariinae
There are seven different species of sea lions. They can grow up to 12 feet in length and weigh up to one ton. Sea lions are carnivorous marine mammals that spend time on land and in the water.
They swim through the water deftly to hunt for food such as fish, squid, and penguins. Though not their main source of food, sea lions do consume a decent amount of krill as well.
8. Antarctic Fur Seal
Scientific name: Arctocephalus gazella
These marine mammals can grow up to 6.5 feet in length and weigh up to 475 pounds. They are most commonly found near Antarctica, hence the name. They range from brown to gray and are excellent swimmers.
They use their torpedo-shaped bodies to bolt through the water hunting for food, mainly krill. The Antarctic fur seal’s diet is about 95% krill. These creatures can eat up to one ton of krill every year.
Scientific name: Teuthida
Squids are cephalopods, meaning they have at least eight legs, a parrot-like beak, and blue, copper-based blood rather than red, iron-based blood. There are over 300 species of squid worldwide, ranging in size from 0.8 inches to over 16 feet long. Their tentacles are covered with suction cups that grab prey and bring it to their mouth.
Squids generally eat small crustaceans, including krill. Squids eat nonstop and consume up to 30% of their body weight in krill and other creatures per day.