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General
Information on
the Bottlenose
Dolphin
CAPTIVITY FACTS
Over half (53%) of the dolphins that survive their violent
capture will die within 90 days. Indeed, dolphins possess a
very sensitive and fragile skin. Any bruise or cut can become
infected very quickly. During capture, dolphins are submitted
to a strong physical and psychological shock. Some of them
can become paralysed and drown. The death rate of capture
is very high. After capture certain dolphins refused to eat,
or ate foreign material, which caused their death. Certain
dolphins have committed suicide by swimming at full speed
against the wall of their tank, breaking their skull.
Transport also makes these animals very vulnerable. For example, in November 1999, four
bottlenose dolphins and one beluga were transferred from Russia to Argentina for display at
the Mar dolphinarium. Two of the four dolphins died on the way.
The average lifespan of a dolphin in the wild is 45
years; yet half of all captured dolphins die within
their first two years of captivity. The survivors last
an average of only five years in captivity. Every seven
years, half of all dolphins in captivity die from capture
shock, pneumonia, intestinal disease, ulcers, chlorine
poisoning, and other stress-related illnesses. To the
captive dolphin industry, these facts are accepted as
routine operating expenses. Although marine mammals
do breed in captivity, the birth rate is not nearly as
successful as in the wild.
CAPTIVITY
Many marine parks subject their mammals to
hunger so they will perform for food. Jumping
through hoops, tail-walking and playing ball are
trained behaviours that do not occur in the wild.
Dolphins use a highly sophisticated “echolocation” system. Confinement in a small tank
may limit the use of this system and generate disorders for the animal. Therefore it is
essential that the tank they are living in, is big enough. Wild dolphins swim 40 to 100
miles per day. In captivity they repeatedly swim in the same small circles. Dolphins in
captivity tend to develop stereotypical behaviours (swimming in a repetitive circle
pattern, with eyes closed in silence) because of boredom and confinement. This is
equivalent to the swaying and pacing of primates, lions, tigers and bears confined in
cages.
Certain aquatic parks keep dolphins in horrible conditions. For example,
in Mexico, a bar called “Paradise” imported four Cuban dolphins, but two
of them did not survive the journey. Throughout the day and during the
night, screaming buggy jumpers descended from the tower above the
dolphin tank on the two dolphins that remained. Noisy bars and discos
surround the pool and bungee jumpers could choose to dunk their heads
into the pool on descent, thus endangering the lives of both humans and
dolphins.
Dolphins are predators of fish and spend up to half of their time in the
wild hunting for food. Supplying dead fish results in less exercise and
lack of mental stimulation, thus causing boredom.
INTERACTION WITH MAN
Bottlenose dolphins show attachment to other species,
especially humans. Indeed, all around the world (USA,
Australia, New Zealand, and Great Britain) some dolphins
have entered into spontaneous relationships with humans.
For example, in 1971, in Florida, the Asburry family who
lived near a canal, started feeding a bottlenose dolphin.
They named her “Dolly”, taught her some tricks and built
her a shelter she liked to use. The dolphin had a very strong
relationship with the mother of the family and behaved like
a child requiring a lot of attention. The Asburry children
became Dolly’s favourite swimming companions.
Dolphins show a particular attachment to children. For
example, in New Zealand, in 1955, a young female called
“Opo”, liked to swim with the children and gave them a
ride on her back. She became a star, performing some
tricks she had invented herself for the pleasure of the
tourists. A similar story occurred in Spain, near La
Corogna. Niña, a female bottlenose dolphin liked to swim
with people, especially the ones wearing diving suits. She
was so famous that she attracted people from all around
Spain, becoming the main source of income for the village
near La Corogna. The inhabitants by recognition have built
a monument of Niña.
During World War II, a dolphin pushed a raft,
containing six American airmen shot down by the
Japanese, to a small island. Dolphins can have very
altruistic behaviour towards mankind.
However, the interaction between man and dolphins
are not always spontaneous. For example, the U.S.
Naval Center, at Point Mugu in California undertake
to train dolphins to accomplish certain tasks.
“Tuffy” a male bottlenose dolphin was used as a
liaison agent between the undersea houses and the
surface. He carried messages, tools and sometimes
he guided lost divers back to the undersea house.
In South Africa and Florida dolphins are trained as “shark watchers”. This program is not
designed to teach
dolphins to attack sharks on sight, but to train them to patrol and give the alarm when
sharks are sighted.
Dolphin therapy
More and more people are becoming interested in the
effect of dolphins on human beings, particularly in
areas such as “dolphin therapy” or “healing people by
dolphin encounters”.
The first research using dolphins with handicapped
children took place at the Ocean World, Fort
Lauderlade, Florida, in 1978. Dr. Nathanson developed
a series of language experiments using dolphins as
teachers for children with Down’s syndrome.
Since that time, many more programmes using dolphins to help disabled children have been
developed. Some special institutes, using the type of treatment, have been created, such
as the Human Dolphin Institute or AquaThough Foundation; a Dolphin Assisted Therapy
Symposium occurred every year, summarising all the progress in that domain.
The emotional therapy
An Encounter with a dolphin is believed to have a
positive psychological impact on humans. The
generation of positive emotions triggers the
release of endorphins (the hormones of well
being) in the brain. This hormone boosts the
immune system and generates a whole set of
self-healing mechanisms in the human
body.
Echolocation/brain theory
Certain scientists study the link
Ultrasound Transducer Probe
between dolphin echolocation
and
2 W/ cm2
modifications in human brain activity.
Indeed, dolphins are able to produce
echolocation sound intensities of 8.3
W /cm2. In comparison, the manBottlenose Dolphin
made source of ultrasound, such as
8 W/cm2
diagnostic and therapeutic transducers
instruments are only 2 W /cm2. The
theory is that these echolocation
sounds would influence the ionic
concentration of nerve cells, thus
inducing
variation
of
brain
Diagnostic
Therapeutic
activity.Dolphin acoustic
emission
Imaging
Ultrasound
increases the left/right hemispheric
synchronisation
(the
brain
wave
emitted from both the left and right
80m W/ cm2
2W/cm2
8.3W/cm2
Maximum
hemisphere of the brain are in phase
Typical
maximum observed
and of similar frequency). In other
words, it calms you down.
Close interactions between humans and dolphins have been shown to reduce stress and
depression significantly. For children suffering from down’s syndrome, the encounters
have improved their cognitive abilities and their co-ordination. Their concentration is
also much better. Autistic children have shown more social interaction following a
close dolphin encounter.