Blue Whale
Wow, that’s big!
Blue whales are simply ginormous! As the largest animals ever to have lived on earth, these marine giants can grow up to 30 metres long, the same as three buses and weigh up to 130,000 kilograms, that’s heavier than 25 elephants or 115 giraffes. Their heart can weigh as much as a car and their tongue as much as an elephant!
They are also the loudest animals on earth, their calls can reach 188 decibels and are even louder than a jet engine, they can be heard many hundreds of miles away.
Where do blue whales live?
Blue whales live in all the world's oceans occasionally swimming in small groups but usually alone or in pairs. They often spend summers feeding in polar waters and undertake lengthy migrations towards the Equator before the winter.
How do blue whales spend their day?
Don’t let their enormous size fool you, blue whales are actually amazing swimmers! They often cruise around the oceans at about 5 miles per hour, but can speed up to more than 20 miles per hour when they need to. Their long, smooth, streamlines bodies help them glide through the water and travel thousands of miles on their incredible ocean journeys.
Blue whales travel alone or in small groups, but have also been found in much larger pods of up to sixty individuals, particularly during periods of feeding.
They migrate to the Poles for the summer months to feed, returning to the calm warmer seas near the Equator for the winter.
Male and female blue whales tend to mate during the winter months, the babies are born a year later. Blue whale calves are already amongst the world’s largest creatures
when they are born, weighing up to 2,700kgs and are nearly eight meters long. It gorges on nothing but its mother's milk for its first year and gains about 200 pounds every day - its growth rate is astonishing and probably the fastest in the animal kingdom.
Blue whales are also some of the loudest animals in the world, their calls to one another can travel for thousands of miles through the ocean! Scientists think that blue whales use these calls to talk to each other, find their way and search for food.
Blue whales are amongst Earth's longest-lived animals and typically live for between 80 and 90 years. However, scientists have discovered that by counting the layers that have formed in a deceased whale's waxlike earplugs, they can estimate their age. The oldest blue whale found using this method was estimated to be around 110 years old.
What do blue whales eat?
Blue whales eat krill, a tiny pale pinkish shrimp-like creature that is around the size of your little finger. Due to their enormous size, a blue whale must eat huge amounts - during certain times of the year an adult blue whale can eat around 30 million krill in just one day!
Billions of krill live in the waters around the north and south Poles; in the summer months the sea can look pink because there are so many. At this time of year, the whales travel to the Poles to feed, growing a thick layer of blubber, or fat, all over it’s body and creating a food store for the winter when the sea has frozen over.
Blue whales are part of a group of ‘baleen’ whales; instead of teeth they have hundreds of baleen plates hanging from their top jaw. Baleen is a tough bendy, fibrous material used to filter their food. To get enough food, the whale takes a huge mouthful of seawater and krill, its throat will expand to let the water in. It then uses its giant tongue to push the water back out through its baleen plates, leaving the krill caught in the plates, just like a sieve.
Why are blue whales so important?
Blue whales are very important to keep our oceans healthy. Everything they do, from swimming to feeding, keeps our oceans full of life, and supports many other fascinating sea creatures!
