A Natural History
Articles:
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The Blue Whale
Source: Jenn Curry | 24-Aug-09
Blue Whales are the largest and most significant mammal (outsizing dinosaurs) to have ever existed and today we are lucky enough to witness this animal in our beautiful oceans.
Blue whales can grow up to 33m in length (equivalent to two buses in length), weigh up to 200 tonnes and have an estimated life span of up to 90 years. In 1966 it became protected by the the International Whaling Commission after being closely hunted to extinction in just 40 years. Records show that approx. 28,350 blues whales were slaughtered by only 41 ships alone in the Southern Waters of one summer in 1930-1931. Populations have twindled immensely worldwide since this extreme hunting began and has never made a full recovery due the the Blue Whales breeding pattern. Numbers have slowly began to come back due to the protection and conservation laws now in place but it is unlikely that the population as it was will ever recover, we can only hope that it will.
LIttle is known about the Blue Whales breeding pattern, and still today noone has ever been lucky enough to record or film a birth. It is believed the gestation period is believed to be between 11-12 months where birth to only one calf is given.
The Blue whales diet consists mainly of Krill (a small shrimp-like crustaceans) and plankton. In order to maintain there adult body weight can require up to 1.5 million calories per day ( a huge amount when we think the average male consumes around 2000 calories per day). This can calculate up to 3500kg of krill per day just for one adult.
Of all whales, Blue whales have the lowest voice vocalizing as low as 14 Hz at volumes of up to 200 decibels which make their calls some of the loudest in the Animal Kingdom. With this frequency and intensity sound can travel over thousands of miles in the deep ocean.
Our oceans are full of maginificent species and it is up to us to respect, protect and conserve what we have, for the future. |
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