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Blue Whale - Balaenoptera musculus
Photo by Dan Shapiro

Blue whales are the largest creatures ever to exist on earth (including the dinosaurs), reaching a length of 34m (110 feet) and weighing up to 120 tons. They are primarily grayish-blue with lighter colored spots. Their undersides often have a yellowish tinge caused by microscopic algae, called diatoms, that attach themselves to the whale's skin. This species is easily identified by its blow, an impressive tall column of spray up to 9m (27 feet) high. Blue whales holds many records in the animal kingdom, yet for all their greatness they are also one of the most endangered.

Blue Whale
(Balaenoptera musculus)

Both temperate and tropical offshore waters, possibly worldwide

Offshore, open ocean



The status of this species is representative of the populations within the waters of this Sanctuary only, not global populations.

Quick Fact
Blue whales have the lowest frequency vocalization of any whale. Reaching as low as 14 Hz with volumes up to 200 decibels, Blue Whales' vocalizations can travel for thousands of miles in the deep ocean.

Learn More
- The National Marine Mammal Laboratory
- Burke Museum of Natural History and Culture