- Majority of small tooth whales are called dolphins.
- They are mammals of the order Cetacea and the families Plantanistidae
and Delphinidae and include about 50 species. All have a beak like snout
and sharp, conical teeth.
- Most dolphin species are about 6 ft in length, the males averaging
4 to 8 in longer than females.
- The largest is the killer whale, which can be 19-22ft long and weigh
between 8000-10000lbs.
- One of the largest dolphins is the bottle-nose dolphin which can reach
over 9ft in length and weigh 440 lbs.
- The smallest species is the buffeo, found in the Amazon River.
- The buffeo rarely grows over 3.9 ft in length and 66 lbs in weight,
really smalled compared to the bottle_nose.
- Dolphins feed on live food and are predators, except when trained
otherwise in captivity. The primary food is fish, mostly things like
herring, mackerel, and sardines. Some species seem to prefer squid,
occasionally, shrimp and other crustacean are consumed, and even mollusk
shells have been found in their stomach contents.
- Food consumption is estimated at about 66 lb a day for an individual
about 8.2 ft in length and 220 lb in weight.
- The body is sleek and smooth and the hairless skin is rubbery to the
touch.
- Most species have jaws that protrude into a beak like snout. Above
the upper jaw is a large mass of fat and oil-containing tissue forming
the so-called "melon" that looks much like a bulging forehead.
- Because dolphins are mammals, they must breathe air and maintain a
high body temperature. The internal temperature, between 97.9 deg to
99 deg F, is acheived by a thick layer of blubber under the skin.
- Air is breathed through blowhole, situated almost directly on top
of the head.
- The dolphin normally comes to the surface to breathe about every two
minutes, and each breath consists of a short, almost explosive exhalation,
followed by a slightly longer inhalation.
- Dolphins can hold their breath for up to several minutes and are capable
of rapid and deep dives of more then 1,000 ft.
- Dolphins are extremely and almost constantly vocal. They are capable
of two kinds of sounds. .
- Dolphins can be found in virtually all the seas and oceans of the
world.
- Dolphins adapt well to human companionship and are readily trained
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