Sunday, 9 February 2014


 Blue Whales evolved from the Indohyus, about 50 million years ago. The closest relative today is the hippopotamus. Up until the early 20th century their numbers would have been fairly stable. The largest population was in the Antarctic, numbering approximately 240,000 (range 202,000 to 311,000).

With the advent of ‘mechanized’ whaling, they were hunted almost to extinction until protected by the international community in 1966. A 2002 report estimated there were only 5,000 to 12,000 Blue Whales worldwide.

Blue Whales tend to live alone or with one other individual but it is not known how long these associations last. Larger feeding groups of 30-50 may form when food is abundant but there does not seem to be the communication typical of a true pod. 

Blue Whale hunting was banned in 1966 but continued illegally in the USSR until the 1970’s. By that time 330,000 Blue Whales had been killed in the Antarctic, 33,000 in the rest of the Southern Hemisphere, 8,200 in the North Pacific, and 7,000 in the North Atlantic. By the time the killing stopped, only about 1 out of every 1000 Blue Whales (0.15%) survived.

Ships carrying whalers are no longer a threat to the Blue Whale but ships carrying cargo are. This summer four were run down by ships further depleting a population that is on the edge of extinction. Ship collisions result from whales and cargo using the same sea lanes for their journeys.

Whale migration:
Blue Whales do a lot of traveling and to better understand how their migrations conflict with shipping, a new generation of scientists is taking to the seas.

Today’s ‘hunters’ attach GPS tags to the Blue Whales to track their positions and record data as they travel. The high-tech devices are attached to the whale in the form of a small harpoon that is imbedded in the blubber.

The GPS tag will only transmit its data above the water when the whale surfaces to take another breath. They spend only about 10% of their time at the surface when they expel a rush of air and spray that can be seen two km away; there she blows!

National Geographic photo used for educational purposes.