Blue Whale Diet 

Blue Whale Diet

     Blue whales are carnivores, although they only eat very tiny things, no bigger than your pinky finger. Their favorite food is krill, or shrimp-like euphausiids, that are up to three inches long. Blue whales must eat two to four tons of krill a day during the feeding season to survive the rest of the year. They concentrate on feeding during the polar summers primarily around the Channel Islands, Monterey Bay, and the Farallon Islands/Cordell Bank. During the winter months, they migrate to the warmer waters in Mexico and Costa Rica.

    The blue whale usually feeds at depths of less than 100 m (330'). 

     Blue whales feed almost exclusively on shrimplike crustaceans known as "krill".  A blue whale may consume up to 5.5 - 6.4 metric tons (6 - 7 tons) of food per day during the summer feeding season. That's 7,715 pounds of krill (small shrimp-like organisms) per day! During the other 8 months of the year, it apparently doesn't eat anything, living off of stored fat.

     The blue whale has long, flexible throat grooves. It feeds by using these groves to expand its throat and drawing in water laden with prey, then forcing the water out through its baleen plates. These plates filter out the prey organisms, which the whale then swallows.

DIET OF THE BALEEN

    All baleen whales are seasonal feeders and carnivores that filter feed tiny crustaceans (krill, copepods, etc.), plankton, and small fish from the water. They are gulpers, filter feeders that alternatively swim then gulp a mouthful of plankton or fish - they lunge into dense groups of small sea organisms (krill or tiny fish) with an open mouth. 50 to 70 throat pleats allow the throat to expand a great deal, forming a "gular pouch." The water is then forced through the baleen plates hanging from the upper jaw. The baleen catches the food, acting like a sieve. 

     The blue whale has about 320 pairs of black baleen plates with dark gray bristles in the blue whale's jaws. They are about 39 inches long (1 m), 21 inches wide (53 cm), and weigh 200 pounds (90 kg). The tongue weighs 4 tons (3.8 tonnes).

An average-sized blue whale will eat 2,000-9,000 pounds (900-4100 kg) of plankton each day during the summer feeding season in cold, arctic waters ( about 120 days).

     The food chain of Baleen Whales is exceptionally simple, it only has three links! Whales like the blue whale feed directly on Zooplankton, the class of tiny marine crustaceans that Krill and plankton belong to. Those in turn feed directly off of Phytoplankton, which are microscopic, free-floating flora. No other mammal on the planet is two steps above microscopic in the food chain, and many find it oddly poetic that this happens to be the largest animal on the planet, by far!