The blue whale (Balaenoptera musculus) is an animal of records. At up to 100 feet in length and weighing 400,000lbs, blue whales are the largest mammals ever known to exist. These jumbo jet-sized whales have a heart that’s the size of a car and a tongue that’s as heavy as an elephant, and inhabit nearly every ocean in the world. Their name is taken from the color they appear to be when underwater; though in fact, blue whales are more a bluish-grey color, with white and yellow pigmentation on their undersides.
Blue whales have a longer, more slender appearance than most whales, with a very small dorsal fin and flippers that are 10-13ft long. They can swim quite fast, up to 31mph, but usually cruise at around 12mph; even slower for feeding. Despite its massive size, the carnivorous blue whale is not a hunter, per se. It instead feeds upon massive schools of krill, a small crustacean not unlike shrimp. Rather than teeth, the blue whale has about 300 rows of baleen plates, which are similar in makeup to fingernails, that are around 3 feet long arranged like a comb. To feed, the whale swims into a school of krill and opens its mouth, engulfing huge amounts of krill and water. The water is then expelled through the mouth, and the remaining krill, stuck in the baleen, are swallowed. Blue whales can eat up to 8000lbs of krill in a day.
These massive mammals inhabit every ocean in the world, usually migrating between the poles in the summer, and back towards the equator each winter. Blue whales are relatively solitary animals, and usually travel alone or in pairs. However, if a good food source is available they will gather in much larger groups.
Scientists do not know much about the breeding habits of blue whales, but do know that females typically birth calves every two to three years. When born, blue whale calves are already 23 feet long and weigh 5000lbs, making them larger than most adult mammals. A calf will live off its mother’s milk for the first six months of life, consuming over 100 gallons of it per day. Young blue whales reach maturity between 5-10 years of age.
Blue whales have a very long lifespan, and usually live for 80-110 years. While their sheer size prevents them from having any natural predators, commercial whaling in the 20thcentury nearly drove the species to extinction. Previously considered too large to catch, by the late 1800’s the technology to hunt these giants had become available, and in the first 60 years of the 20thcentury more than 330,000 of these whales had been caught. Blue whale hunting was banned in the 1960’s, and the remaining population of these whales is estimated at less than 12,000.
BLUE WHALE FACTS
- The spray from a blue whale’s blowhole reaches 30 feet in the air.
- Blue whale calves gain 200lbs a day, every day for their first year.
- Despite its massive size, the blue whale’s throat is so small it cannot swallow anything larger than a beach ball.