Vocalization of Blue Whales
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.
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