The blue whale is the world's biggest animal, weighing up to 200 tons. The heart of a blue whale is equivalent to a Volkswagen Beetle. Its stomach can transfer one ton of krill, and it requires roughly four tons of krill per day to survive. They are the most audible animals on the world, just more so than a jet engine. Their calls have a decibel level of 188, whereas a jet has a decibel level of 140. Their low-frequency whistle, that can be heard for hundreds of kilometers and is most likely often used to attract other blue whales, is presumably also used to attract other blue whales.
Appearance and coloring
Blue whales seem genuine blue underwater, but their pigmentation is mottled blue-gray on the surface. The millions of bacteria that take up home in their skin give their underbellies a yellowish color. The blue whale's head is large and flat, and its body is long and tapering, ending in wide, triangle flukes.
Behavior and vocalization
Blue whales can be found in all of the world's oceans except the Arctic, and they normally swim alone or in pairs. Summers often eat in polar seas, followed by long migrations to the Equator as snow melts.
When they are relaxed, these beautiful swimmers cruise in the ocean at speeds of much more than five miles per hour, but they can reach speeds of more than 20 miles per hour when they are disturbed. Blue whales are one of the world's loudest creatures. Blue whales emit a sequence of groans, pulses, and moans, and it's thought that they can hear one another up to 1,000 miles distant in good conditions. Scientists believe they employ these vocalizations to communicate and sonar-navigate the dark ocean depths, thanks to their exceptional hearing.
Longevity
Blue whales are one of the planet’s most long-lived creatures. Scientists have found that counting all layers of a dead whale's wax-like earplugs can estimate an accurate age. The largest blue whale discovered using this technique was approximately 110 years old. The average lifetime is thought to be between 80 and 90 years.
Where do they live?
Except for the Arctic Ocean, blue whales can be found in all oceans. They travel periodically between summertime nesting sites and winter breeding sites. However, some data suggest that some individuals may not migrate at all in certain places. Distribution and movement information varies by area, and migration routes are unknown. They generally occur in areas where krill are concentrated, and their dispersal is mostly determined by food availability. Their range in the North Atlantic Ocean stretches from the southern hemisphere to the Greenland Sea. Blue whales have been marked in the coast of eastern Canada and even in the eastern United States' shelf seas.
East North Pacific blue whales are thought to spend their winters in Mexico and Central America off the west coast of the USA. They are most likely to feed in the summer off the west coast of the USA and to a lesser degree in the Gulf of Alaska & central North Pacific seas. From December through March, blue whales with young calves are seen in the Gulf of California. This location is thought to be vital for the species' calving and nursing.
Conservation
Whalers seeking whale oil hunted them aggressively in the 1900s, bringing them to the verge of extinction. 362,000 blue whales were killed during 1900 and the mid-1960s. They were finally protected in 1966 by the International Maritime Organization, but they've only made a tiny comeback since then.
Although blue whales have very few predators, they have been attacked by sharks & killer whales and are damaged or killed each year due to collisions with large ships.
