The blue whale is the largest animal alive today and one of the largest animals ever – rivalled only by the largest dinosaurs; the titanosaurs.
The species is thought to feed almost exclusively on small, shrimp-like, crustraceans called krill. In the summer feeding areas, individuals may consume as much as 4 tonnes of krill each day. Blue whales have the deepest voice of any animal, and their vocalisations carry for thousands of miles underwater, allowing them to communicate across vast oceans as frequencies below the range of human hearing. For centuries the blue whale was safe from exploitation because of its sheer size and speed. However, the species was driven to the brink of extinction following the development of modern whaling techniques. They are also under threat from shipping practices, with occasional ship strikes, but also the disturbances of ship traffic and ship noise, though the impact of these is not fully known.
- Order: Cetartiodactyla
- Family: Balaenopteridae
- Population: <5,000
- Trend: increasing
- Size: 25-27m
- Weight: up to 190,000kg
The blue whale occurs in the Arctic, Atlantic, Indian and Pacific Oceans, from the tropics to the drift ice of polar waters.
Habitat and Ecology
Blue whales inhabit the open ocean in both cold and temperate waters. Often found along the continental shelf edge and near polar ice. They are thought to feed almost exclusively on small, shrimp-like crustaceans (krill). They are usually seen alone, or in small groups of two to three individuals, although groups of up to 60 may form in areas where food is plentiful. Blue whales are migratory, with most individuals spending the summer feeding in high-latitude regions and returning to warmer waters in the winter for mating and calving.