|
Links for more information:
Day in the life of a zoo keeper
SeaGrant
DolphinTrainer.com
Dolphins are intelligent, social animals capable of exhibiting
a wide variety of behaviors. These behaviors can be instinctive,
such as swimming, breathing and eating, or learned as a result
of practice or experience. When a human is involved in shaping
an animal's behavior we call it training.
Dolphins, like all animals, learn in a variety of ways. At the
Minnesota Zoo we use operant conditioning techniques to train
dolphins. Operant conditioning is a type of learning in which
an animal's behavior changes in response to the consequences which
follow the behavior. If the consequences which follow a behavior
are positive to that animal, the animal is likely to repeat the
behavior. Anything which increases the frequency, duration or
intensity of a behavior is a reinforcement. Anything which decreases
the frequency, duration or intensity of a behavior is punishment.
The training at the Minnesota Zoo is based on reinforcing desired
behavior. Because a positive relationship between the dolphin
and its trainer is important for successful training , negative
experiences (punishment) are avoided. To put it simply, we positively
reinforce desirable behavior and ignore undesirable behavior.
A variety of things can be reinforcing for a dolphin. Each animal
is an individual with its own likes and dislikes. Learning what
is reinforcing for a particular dolphin requires a great deal
of patience and careful observation. One thing which is positive
to all animals is food. Food is considered a primary reinforcement
because it is necessary to sustain life. You can teach a dolphin
to respond to a new reinforcer by pairing it with a known positive
reinforcer such as food. Eventually the dolphin starts to associate
the new reinforcer (for example: squirting the dolphin with water)
with the positive experience of being fed and the new reinforcer
becomes positive all by itself. This new reinforcer is called
a secondary reinforcer. Here at the zoo we use a variety of secondary
reinforcers, such as: splashes of water, rubdowns, verbal praise
and toys. Each dolphin has certain areas of the pool they like
to swim in, behaviors they like to perform, or other dolphins
they seem to like to work with at certain times. These can all
be used as reinforcers as well.
In order to successfully train a dolphin, the trainer needs to
reinforce the dolphin at the instant the dolphin performs a desired
behavior. At the Minnesota Zoo a whistle is used as a signal to
the dolphin when it is doing a good job. Early in the training
a whistle is paired with food. The dolphins learn to associate
the whistle with the food so the whistle becomes a secondary reinforcer.
Although the whistle itself is reinforcing it is primarily used
to bridge the gap between the time a desired behavior occurs and
when the dolphin will be reinforced with food or some other reinforcement.
The whistle is called a bridging signal or bridge.
Many of the behaviors the dolphins perform at the Minnesota Zoo
are behaviors commonly observed in the dolphins in the wild. We
train many of the behaviors by watching the dolphins and reinforcing
them when they offer a desired behavior.
To train some behaviors we need to lead the dolphin through the
behavior in steps. We can do this by training the dolphin to follow
a target. The target is a focus point for the dolphin, something
that directs the dolphin, usually our hand. A long stick with
a float on the end of it (an extension of our hand) can also be
used as a target for behaviors that take place farther away. Once
the dolphin learns to follow a target, a variety of behaviors
can be shaped.
Since the dolphins perform many different behaviors we need a
way to let the dolphin know when to perform a specific behavior.
A visual, tactile or auditory signal can be used to cue the animal
to do a particular behavior. At the zoo we primarily use hand
signals. When training a new behavior, a specific hand signal
is paired with the behavior while it is being trained. For example;
a target is used to move the dolphin in a spinning motion. The
dolphin would be shown a hand signal just before the target is
presented. The dolphin begins to associate that hand signal with
the spinning behavior. Eventually the hand signal alone will elicit
the spinning behavior and the target will no longer be necessary.
Each hand signal corresponds to a specific behavior and the dolphins
learn to discriminate between the different signals. If a specific
hand signal is given, and the dolphin does not respond or responds
incorrectly, it is not reinforced. It doesn't take long for the
dolphins to figure things out.
Ensuring the health and well being of the dolphins is of paramount
importance. By using the same training techniques previously described,
we can train the dolphins in a variety of what are know as husbandry
behaviors. These are behaviors which allow us to constantly monitor
the health of the dolphins. Using positive reinforcement we can
train the dolphins to allow us to take a blood sample, obtain
a bacterial culture of their blowhole, inspect the inside of their
mouths, and lay in a variety of positions which allow our veterinary
staff to conduct a visual exam. All of these behaviors are done
in a pool without physical restraint.
Dolphins are often perceived as leading a carefree existence;
frolicking about the oceans with a perpetual smile. The dolphin's
smile is simply the line of its jaw, and life in the ocean is
not always worth smiling about. The ocean is a hostile environment
and dolphins spend a majority of their time searching for food
and avoiding predators. Good or bad, the ocean is definitely stimulating.
Here at the Minnesota Zoo the dolphins have no predators and we
feed each of the dolphins approximately 25 pounds of fish a day.
One of the reasons we train the dolphins is to provide a stimulating
environment for them, challenging them mentally and physically.
Dolphins can be fascinating animals to observe, both in the ocean
and in a zoological setting. Unfortunately most people will never
get the opportunity to see them in the wild. A public presentation
with dolphins performing a variety of behaviors increases the
public's awareness of the unique abilities of dolphins, thus educating
through entertainment.
Most of what we know today about dolphin physiology, reproduction
and behavior has been learned from dolphins in zoos and oceanaria.
Many questions about dolphins remain as yet unanswered. Information
gathered from studying dolphins in a zoological setting, combined
with field observations, will help scientists conserve wild populations.
|