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Blue Whale

Balaenoptera musculus

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With adult specimens measuring up to 98 feet (30 m) in length, no animal, either terrestrial or marine, modern or prehistoric, has come close to the sheer size of the Blue Whale. This gentle and reclusive cetacean is the largest animal to ever live on Earth. The whales are so big that when they spout their spray has been recorded as reaching 30 feet (9.1 m) into the air. Their newborns measure over 25 feet (8 meters) in length and weigh as much as 3 tons (2.7 metric tons). They are also the largest carnivore, although they prey almost exclusively on tiny shrimp like animals called krill. They use fringed plates of baleen attached to the upper jaw to filter their food out of the water. The baleen acts like a net which catches the krill but allows water to pass through. A typical adult whale may consume up to 4 tons (3.6 metric tons) of krill every day. That’s comparable to a human being eaten 32,000 quarter-pound hamburgers each day!

Because the whales are so large, they are difficult to photograph or even observe in the natural environment unless done from the air. Still, Blue Whales can be identified by a long, tapering body which is more slender than most other whale species. The head is flat and has a distinctive U-shaped crest which reaches from the blowhole around the perimeter of the upper jaw. Compared to its size, it has an extremely small dorsal fin. The body color is gray in most individuals, although it can sometimes be mottled with patches of darker gray, black or blue.

Range and Habitat

Blue Whales are found in every ocean on Earth but do not roam to the polar regions. They are pelagic animals, meaning they live almost exclusively in the open ocean, rarely straying into coastal areas near land. They stay close to the surface of the water where krill is plentiful and generally live in extended family groups called pods.

Conservation Status

Prior to their population being decimated in the 1900s, Blue Whales existed across the globe in large pods, which could number 230,000 or more individuals. Today, the whale is listed as endangered by the The International Union for the Conservation of Nature (IUCN). Like all whales, hunting of the Blue Whale is prohibited by US law and they are protected in US territorial waters.