The largest mammal ever to inhabit the Earth, the Blue Whale in an endangered species, with a population estimated at around 1,500. They average about 25m in length and generally weigh a massive 100,000kg. It’s heart is the size of a car. Blue Whales migrate towards Polar region in Spring, to feed on the plentiful zooplankton stock and move south in Winter to reduce energy expenditure while fasting, avoid ice entrapment, and breed in more temperate waters of the subtropics. Between 1920-1960 Blue Whales were hunted extensively and numbers were greatly depleted to the point of near extinction. They are now protected under the Endangered Species Act and the Marine Mammal Protection Act but are still threatened by illegal whaling practices and interactions with boats, for example entanglement in lines or collisions with vessels.