The largest creature of our time, their average size ranges between 100 and 110 ft in length and their average weight is 200 tonnes. Marine scientists still know very little about them, their breeding patterns for instance are not understood at all.
Blues like all Baleen whale species were hunted to the extreme in the 19th and 20th century, it's estimated that about 10,000 still remain, they don't have a natural habitat, they roam the open water, for instance one was spotted off the Mayo coastline a couple of years back. Beautiful creatures, this guy working off the coastline of Sri Lanka has captured great unique footage of them.