Dolphins
Dolphins - the subject of
many legends and stories are perhaps the most beloved
sea creatures. These beautiful, fascinating and very
intelligent sea mammals populate all the seas in the
world and some even live in fresh river waters in Asia
and South America. An example being the tucuxi
dolphin in the Amazon River. The tucuxi is also
the smallest of the dolphin species being about 4 foot
in length. The bottled - nose dolphin is one
of the largest with an approximate length of 10 feet.
But actually the largest of the dolphin family is the
killer whale which can reach a length of 30 feet.
There are about 32 species of dolphins, all related
to whales and porpoises. Perhaps the most popular
are the playful and gracious swimmers, the bottled
- nose dolphins.
Dolphins breathe through a
blowhole on the top of their cone-shaped heads. They
produce a clicking or whistle-like sound. The clicking
sound, similar to the navigation technique of the bats,
helps dolphins locate objects through echo. The whistling
sound is used mostly for communication between their
own species. Their diet consists mostly of fish and
squid. Chewing their food with 200 -250 sharp teeth,
dolphins eat up to one third of their own body weight
daily. With their streamlined bodies, they can reach
a speed of up to 25 mph. when swimming. The lungs of
dolphins adapt quickly to changes of pressure in deep
waters and they are able to dive to a depth of more
than 1000 feet. Dolphins give birth to one calf which,
after a gestation period of 11 or 12 months, is born
tail first.
Dolphins are protected
through the Marine Mammal Protection Act of 1972 (amended
in 1988 and 1992).
Bottled - nose dolphin
in Hawaii. Photo by Joyce E. Robertson.
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