Blue whales are the largest and one of the most extraordinary creatures to have existed on Earth, even when taking dinosaurs into account. They easily measure up to 100 feet plus long and can weigh up to 200 tons. A blue whale’s tongue weighs as much as a full grown elephant and its hearts as much as a vehicle. Even the biggest one of all the dinosaurs is skinnier in comparison to the blue whales. There is possibly no way a blue whale could be a terrestrial animal as it requires water to support its weight. It would probably have crushed itself if it was on land.
Blue whales reach unbelievable dimensions on a diet almost exclusively composed of tiny shrimp-like animals called krill. They however, also take up small numbers of copepods at times. Blue whales are deep-water hunters which feed in the areas with highest concentration of krill, sometime eating up to 40 millions krill a day. Since krill move, blue whales descend during daytime in order to feed as deep as 500 meters and surface-feed at night. The dive during feeding is typically 10 minutes long and can go up to 20 minutes or more.
The whale feeds by lunging forward where groups of krill are present, and then takes gulps in the animals along with enormous mouthful of water. The water is then forced out through the animal’s massive tongue while filtering its main source of food behind i.e. the krill with the help of baleen, a row of these amazing fringed plates in the giant animal’s mouth. Once the water is out of the mouth, thousands of krill which remain behind, unable to pass through baleen, are swallowed by the whale.
It is not just the size of these animals that make them extra ordinary, but also the fact that they are timid, rarely seen mystical creatures which are very few in numbers. In fact this vulnerable underwater heavyweight animal remains on the endangered species list. Commercial whaling, which was only came to an in 1986, caused a severe depletion in the numbers of Blue whale. Experts believe that about 99% of the blue whale population was wiped off through whaling.
Blue whales are found in all the oceans of the world, specifically more in the Southern Hemisphere. Average estimated lifespan of a blue whale ranges between 80 to 90 years. Due to their dependence on one kind of species for food, Blue Whale may suffer as a result of any depletion in the population of krill by fishing or global warming.