Blue whales are the largest animals ever to have lived - bigger even than the largest of the dinosaurs. These jumbo-jet-sized giants inhabit the open ocean, where they are found most frequently along the continental shelf edges and near polar ice. A single calf is produced every two to three years, and from birth each calf consumes up to 50 gallons of milk every single day, leading to a colossal weight gain of 90 kilograms per day in its first year of life.
Did you know?
A blue whale's blood vessels are wide enough for a human to swim through.
Scientific name: Balaenoptera musculus
The giant of the ocean in all its majesty.
Blue whales are symbolic ocean giants. Yet despite their size and apparent visibility, they've rarely been filmed in any detail and comparatively little is really known about their life and its habits. As Sir David points out, if so little is known about these giants, how much less is known about the myriad smaller creatures of the seas.
The anatomy of the largest mammal ever to have existed.
Everyone has heard of the blue whale, yet they are rarely seen and not often filmed. Sir David's delight at the privileged close up view of one of these ocean giants as it breached right beside him is evident. Although difficult to comprehend, at 30 metres in length and 180 metric tons or more in weight, the blue whale is the largest animal ever known to have existed.
A comparison of the mighty blue whale's size in relation to humans.
The following habitats are found across the Blue whale distribution range. Find out more about these environments, what it takes to live there and what else inhabits them.
Discover what these behaviours are and how different plants and animals use them.
Additional data source: Animal Diversity Web
Population trend: Increasing
Year assessed: 2008
Classified by: IUCN 3.1
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