Behavior of Blue Whales continued

Vocalization

     Blue whales have very deep voices and can vocalize at a volume of greater than 180 decibels, the loudest sound of any animal. These sounds can be characterized as grunts, hums, moans, and clicks. Blue whales have very deep voices, vocalizing at frequencies as low as 14 Hz - below the range of human hearing - at a volume of greater than 180 decibels, the loudest sound of any animal. They are highly structured, repetitive low-frequency sounds that can travel for many miles underwater. Not only are they the loudest animals alive, they are even louder than a jet engine!

     Their songs may be used for locating large masses of krill (tiny crustaceans that they eat) and for communicating with other blue whales, especially in order to attract and find mates.

Swimming

     The blue whale ranks among the fastest of the whales, with feeding speeds of 2 - 6.5 km/h (1.2 - 4 mi/h) and cruising speeds of 5 - 33 km/h (3 - 20 mi/h). When chased, it can reach speeds as high as 48 km/h (30 mi/h). Feeding speeds are slower, about 1-4 mph (1.6-6.2 kph).

Diving

     The blue whale usually feeds at depths of less than 100 m (330'), up to 200 m (660'). A dive usually lasts 10 - 20 minutes, and up to an hour. When making a deep dive, the whale "headstands," exposing its wide tail flukes, then descends steeply. Its long, narrow flippers play no part in propulsion - the thrust comes from the powerful back muscles that swish the rear body and flukes up and down. On returning to the surface, the whale releases a "blow," about 9 m (30‘) high, consisting of warm, humid air from the lungs, mucus, and ocean water. 

Early Development:

     A calf is weaned at about 6 - 8 months, when it is about 16 m (52') long. Mothers form a very tight bond with babies until then, never leaving its side.

Dispersal:

     After it is weaned, a calf leaves its mother to follow the normal migration pattern independently.