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Mammals are warm-blooded animals that have lungs and need to breathe air
to live. They give birth to live young, unlike for example birds, turtles,
and fish that lay eggs. Mammals nurse their calves. Cats, dogs, seals,
bears, dolphins and humans are examples of mammals. While humans are mammals
that live on land, dolphins are mammals that have adapted perfectly for
life in the sea. We call them marine mammals.
Warm-blooded animals can control their body temperature. This means that
their body temperature does not change as the temperature varies and changes
around them. Reptiles and fish are cold-blooded animals. Their blood temperature
changes with the temperature of their surroundings.
Bottlenose dolphins have a worldwide distribution, from temperate to tropical
waters. Some stay within the same area along the coast all year round.
Others live in the deep water far out at sea and travel long distances.
According to some researchers, dolphins in the wild live an average of
35 years. Females live longer than males. Some females have been recorded
at over 50 years of age.
In general, male bottlenose dolphins are bigger than females. A male bottlenose
dolphin can grow up to 410 cm. (161 inches.)A female can grow up to 325
cm. (128 inches.) The size of bottlenose dolphins varies with location.
The bottlenose dolphins found in Britain, Europe, for example, are bigger
than the ones found in Florida, USA.
All cetaceans are voluntary breathers. This means that the dolphin decides
when to breathe, unlike humans, who breathe without even thinking about
it. For instance, when you sleep, you breathe automatically. A dolphin
has to remember to breathe. Therefore, dolphins can’t sleep the way
we can. Some researchers think that dolphins only sleep with half of their
brain, while the other half stays awake so that the dolphin remembers
to take a breath when it needs fresh air.
Dolphins breathe through a single blowhole, which is located on the top
of their head. Dolphins hold their breath while they swim underwater.
The blowhole has strong muscles that keep the blowholes shut tight so
that water doesn’t get in and cause the dolphin to drown. When a
dolphin needs a breath of fresh air, it swims toward the surface of the
water and starts exhaling. The moment the dolphin breaks the surface of
the water and the blowhole is no longer under water, the dolphin inhales
a breath of fresh air. Then the dolphin dives back into the ocean. It
takes less than a second for a dolphin to take a breath of fresh air.
While swimming, dolphins surface two or three times per minute. However,
they can easily stay underwater for up to 10 minutes.
They can reach a speed of 37 km/hr that’s nearly 23 miles per hour!
What is this in MPH; about 21?).
Bottlenose dolphins can dive to depths of more than 1640 feet (500 meters).
Depending on what’s available in the particular area they live in,
bottlenose dolphins eat fish, such as mullet, flying fish, and catfish.
They also eat rays, crabs, octopus, squid, crustaceans, jellyfish, and
shrimp.
No. They use their sharp, pointed shaped teeth to hold on to the slippery
fish, which they swallow whole, headfirst.
Following the fish they eat, bottlenose dolphins swim up to 40 miles per
day.
They have good eyesight, both below and above the water.
Dolphins, by Chris Catton
Bottlenose Dolphins,
by Paul Thompson & Ben Wilson
Dolphins & Porpoises, a Worldwide Guide,
by Jean-Pierre Sylvestre
Dolphins, by
Erik D. Stoops, Jeffrey L. Martin & Debbie Lynne Stone
Reprinted with the permission of the Dolphin
Project.
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