Facts About Blue Whales
Blue whales (Balaenoptera musculus) are the largest known animals to have ever lived on the planet. They eat the equivalent of a mature African elephant every day. They can grow to up to 33.6 metres in length, almost as long as a Boeing 737 and can weigh up to 200 tons. Their hearts can weigh as much as an automobile and their tongues can be as heavy as an elephant. Blue whales swim with grace and power, cruising at around 5 miles an hour and powering up to speeds of over 20 miles an hour when required.
Diet
This astonishing ability to grow to such huge proportions is achieved through a diet mainly consisting of one of the smallest animals on the planet called krill. These are minute shrimp-like creatures that are an essential part of the marine food chain for many other sea creatures. A single adult blue whale can eat around 3.6 tonnes (4 tons) of krill in a single day. They also supplement their diet with pelagic crabs.
Baleen Plates
Blue whales are of the baleen group of whales and have plates made of a substance similar to human finger nails on their upper jaws called baleen plates.
As they swim through the water they open their mouths taking in great gulps of sea water. They have pleated skin on their underbelly and throat which expand to take it in. Their huge tongue pushes the water through the thin, baleen plates and the krill is left behind and swallowed by the whale.
Communication
The voice of the blue whale is thought to be one of the loudest in the animal kingdom. They emit low- frequency sounds of moans, pulses and groans that carry in deep water for hundreds of miles. They are believed to be able to hear each other 1,000 miles apart. No one knows whether the purpose of this is for communication over long distance or whether it is used for finding their way in the darkness of the ocean, assisting with orientation and navigation.
Range
Blue whales are found in all the oceans of the world and range from the tropics to the poles though in some areas they are less frequently found. Some populations of blue whale migrate long distances between high latitude feeding grounds in the summer to low latitude breeding grounds in the winter.
Populations
Although blue whales do swim in small groups at times they are more often seen in pairs or on their own. In some places populations of blue whales appear to be resident and do not migrate. The only population of blue whales that appear to be thriving spends its summers off the coasts of Mexico and California.
A sub-species known as the pigmy blue whale is found in the Indian Ocean may eventually be recognised as a separate species.
This astonishing ability to grow to such huge proportions is achieved through a diet mainly consisting of one of the smallest animals on the planet called krill. These are minute shrimp-like creatures that are an essential part of the marine food chain for many other sea creatures. A single adult blue whale can eat around 3.6 tonnes (4 tons) of krill in a single day. They also supplement their diet with pelagic crabs.
Baleen Plates
Blue whales are of the baleen group of whales and have plates made of a substance similar to human finger nails on their upper jaws called baleen plates.
As they swim through the water they open their mouths taking in great gulps of sea water. They have pleated skin on their underbelly and throat which expand to take it in. Their huge tongue pushes the water through the thin, baleen plates and the krill is left behind and swallowed by the whale.
Communication
The voice of the blue whale is thought to be one of the loudest in the animal kingdom. They emit low- frequency sounds of moans, pulses and groans that carry in deep water for hundreds of miles. They are believed to be able to hear each other 1,000 miles apart. No one knows whether the purpose of this is for communication over long distance or whether it is used for finding their way in the darkness of the ocean, assisting with orientation and navigation.
Range
Blue whales are found in all the oceans of the world and range from the tropics to the poles though in some areas they are less frequently found. Some populations of blue whale migrate long distances between high latitude feeding grounds in the summer to low latitude breeding grounds in the winter.
Populations
Although blue whales do swim in small groups at times they are more often seen in pairs or on their own. In some places populations of blue whales appear to be resident and do not migrate. The only population of blue whales that appear to be thriving spends its summers off the coasts of Mexico and California.
A sub-species known as the pigmy blue whale is found in the Indian Ocean may eventually be recognised as a separate species.
Appearance
Although blue whales look blue underwater they are more of a speckled bluish grey colour. Their underbellies have millions and millions of microscopic organisms that live on the skin giving it a yellowish colouration. The head of the blue whale is quite wide and flat. Its body is long and tapers into a wide pair of triangular flukes.
Reproduction
They have a gestation period of around ten to twelve months and tend to give birth every two or three years. A baby blue whale is born as one as the biggest creatures on earth. At birth they can weigh as much as three tons with a length of around 25 feet. For the first year the calf will be nourished on its mother's milk which is so rich in nutrients that it will gain around 200 pound daily.
Longevity
Blue whales have one of the longest life spans of any animal on Earth. According to scientists the age of a dead blue whale can be estimated by counting the wax-like layers that form in it ears. So far the oldest they have found was estimated to be 110 years old by this method. Blue whales are estimated to have a lifespan of 80 to 90 years.
Status
During the period of mass whaling, from 1900 up until the mid 1960s, around 360,000 were slaughtered. They verged on the brink of extinction before finally coming under the protection of the International Whaling Commission in 1966. Today, they have managed only a partial recovery. Estimates of the total population of blue whales are uncertain, but there are believed to be between 10,000 and 25,000.
Predators
A part from humans, blue whales have few predators. Some are killed or injured through collisions with ships and others fall victim to attacks from sharks and orca whales. Some become beached on shore though the reasons for this are uncertain. The World Conservation Union, places them on their Red List as Endangered.
© 30/03/2014 zteve t evans
Although blue whales look blue underwater they are more of a speckled bluish grey colour. Their underbellies have millions and millions of microscopic organisms that live on the skin giving it a yellowish colouration. The head of the blue whale is quite wide and flat. Its body is long and tapers into a wide pair of triangular flukes.
Reproduction
They have a gestation period of around ten to twelve months and tend to give birth every two or three years. A baby blue whale is born as one as the biggest creatures on earth. At birth they can weigh as much as three tons with a length of around 25 feet. For the first year the calf will be nourished on its mother's milk which is so rich in nutrients that it will gain around 200 pound daily.
Longevity
Blue whales have one of the longest life spans of any animal on Earth. According to scientists the age of a dead blue whale can be estimated by counting the wax-like layers that form in it ears. So far the oldest they have found was estimated to be 110 years old by this method. Blue whales are estimated to have a lifespan of 80 to 90 years.
Status
During the period of mass whaling, from 1900 up until the mid 1960s, around 360,000 were slaughtered. They verged on the brink of extinction before finally coming under the protection of the International Whaling Commission in 1966. Today, they have managed only a partial recovery. Estimates of the total population of blue whales are uncertain, but there are believed to be between 10,000 and 25,000.
Predators
A part from humans, blue whales have few predators. Some are killed or injured through collisions with ships and others fall victim to attacks from sharks and orca whales. Some become beached on shore though the reasons for this are uncertain. The World Conservation Union, places them on their Red List as Endangered.
© 30/03/2014 zteve t evans
References and Attributions
© 30/03/2014 zteve t evans
File:BlueWhaleWithCalf.jpg From Wikimedia Commons – Blue Whale with Calf, Ólafsvík, Iceland - Author: Andreas Tille Creative Commons Attribution-Share Alike 3.0 Unported, 2.5 Generic, 2.0 Generic and 1.0 Generic license.
National Geographic - Blue Whale Balaenoptera musculus
The Marine Mammal Centre – Blue Whale
BBC, Nature – Wildlife – Blue whale
© 30/03/2014 zteve t evans
File:BlueWhaleWithCalf.jpg From Wikimedia Commons – Blue Whale with Calf, Ólafsvík, Iceland - Author: Andreas Tille Creative Commons Attribution-Share Alike 3.0 Unported, 2.5 Generic, 2.0 Generic and 1.0 Generic license.
National Geographic - Blue Whale Balaenoptera musculus
The Marine Mammal Centre – Blue Whale
BBC, Nature – Wildlife – Blue whale