Blue whales are truly awe-inspiring creatures. They are the largest animals to have ever existed—bigger than even the largest dinosaurs. The largest blue whales have reached a maximum confirmed length of 98 feet (29.9 m) and can weigh as much as 200 tons. Incredibly, their hearts are as large as a small car and their tongues can weigh as much as an elephant.
Antarctic blue whales reach these incredible sizes by feeding almost exclusively on tiny shrimplike animals called krill, which flourish in Antarctic waters. An adult blue whale can eat as much as four tons of krill a day. They achieve this by lunge feeding, in which they accelerate toward large patches of krill, open their mouths wide and take in huge amounts of krill-laden water—more than 100 tons of water in one go. They then squeeze out the water and swallow the remaining krill.
Blue whales normally swim alone or in pairs but sometimes form small groups. They tend to spend the summer months in Antarctic waters and then migrate toward equatorial waters when winter arrives, although research suggests that some individuals don’t migrate, or at least not every year.
The spectacular size of the blue whale is matched by its bellowing call. They are the loudest animals on Earth, and their low frequency calls can be heard for hundreds of miles, although some of the lowest frequency calls are too low for human hearing. Up close, the blue whale’s call reaches a tumultuous 188 decibels, louder than a jet engine. These calls are probably used to attract other blue whales.
Sadly, Antarctic blue whales are now classified as endangered. Their numbers were decimated by whale hunters in the early- to mid-1900s and never truly recovered. There were once some 225,000 individuals in Antarctic waters, while today there are probably less than 2,000. Recently, however, there have been some positive signs. A team of scientists led by the British Antarctic Survey counted 55 Antarctic blue whales during a single expedition in 2020, a number they described as “unprecedented.”
Other Antarctica Wildlife
Adélie Penguin / Chinstrap Penguin / Emperor Penguin / Gentoo Penguin / Macaroni Penguin / Crabeater Seal / Elephant Seal / Fur Seal / Leopard Seal / Ross Seal / Weddell Seal / Fin Whale / Humpback Whale