What Is The Largest Mammal?

Skeleton of a blue whale adorns the central hall of a museum. Editorial credit: akedesign / Shutterstock.com
Skeleton of a blue whale adorns the central hall of a museum. Editorial credit: akedesign / Shutterstock.com

The largest living animal in the world is the Blue Whale. The species is about 98 ft long and weighs approximately 173 metric tons. It is a marine mammal which belongs to the baleen whale parvorder. The biggest living land animal is the African elephant, although numerous extinct mammals were believed to be bigger like the Paraceratherium. The latter is an extinct member of the hornless rhinoceros and one of the biggest terrestrial mammals to have ever existed.

Description Of The World's Largest Mammal

Blue whales have elongated tapering bodies which seems stretched as compared to other members of the infraorder Cetacea. They have U-shaped, flat heads which have a ridge which stretches from the blowhole to the upper lip. The front part of the mouth has over 300 baleen plates (which are 3.3ft long) which hang from the upper jaw and stretches for about 20 inches into the mouth. The blue whale has a smaller dorsal fin (11 inches) which is only visible when it is diving. The dorsal fin varies in shape from one blue whale to another with some having sickle-shaped dorsal fins. The blue whale has a lung capacity of about 1,300 U.S. gallons. Its flippers are roughly 13.1ft long. The upper side of the whale is grayish with a thin white boundary, while the lower side is white. The tail fluke and head of the blue whale is grey. The species can attain a maximum speed of about 31mph. When the whales are migrating, they swim at a depth of over 43ft to avoid the drag from the water waves on the surface.

How Big Is the Blue Whale?

The blue whale from Pacific and Northern Atlantic are smaller than the ones living in the Antarctic. Female blue whales are longer than the males while the latter are slightly heavier. The adult blue whales weigh between 45 to 136 metric tons with the heaviest weighing about 173 metric tons. The heaviest whale was measured in 1947. The longest female blue whale ever recorded was about 110 ft long. Due to the extreme size of the blue whale, all its body organs are the biggest in the animal kingdom. Its tongue weighs about 2.7 metric tons, and when expanded, it has the capacity of holding about 90 tons of water and food. At birth, the young blue whales weigh about 5,950 pounds.

Diet of Blue Whales

These animals feed mainly on krill and numerous copepod species. An adult blue whale can consume about 40 million krills per day. Blue whales feed in places with a high concentration of krill, and they can eat about 7,900 pounds of food daily. Since krills move around, the blue whales usually surface-feeds at night and during the day they feed at a depth of approximately 330 ft. They also feed on squid, crustaceans, and small fish which are captured with the krill.

Threats to Blue Whales

Initially, the blue whales were not easy to catch due to their size and therefore many whalers rarely pursued these creatures. However, when Svend Foyn, a Norwegian whaling magnate, installed bigger harpoons on a steamboat in 1864, these whales became the target of the whalers. Initially, the harpoons were cumbersome and therefore had a low success rate, but with time Foyn perfected the harpoons, and they were able to capture blue whales.

Sadly, with the success of the whaling technique, whalers started hunting blue whales indiscriminately in Spitsbergen (1903), Newfoundland (1898), the Faroe Islands (1894) and Iceland (1883). Over 29,400 blue whales were captured from 1930 to 1931 in the Antarctic alone. Hunting of the mammals was prohibited in 1966 by the International Whaling Commission when it was realized that such hunting could soon render these beautiful creatures extinct.


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