In "Social Behavior in Bottlenose Dolphins" (Shane Watson, unpublished research report, University
of Nevada Las Vegas, 2009) socialization behavior of captive Bottlenose dolphins was studied. A summary of this report yields
the following information on this topic:
The development of individual
behavior in dolphins acts to mold their social structure and how they cooperate with each other. They live in complex social
societies. These societies differ dramatically between genders. In the wild, these developments may have evolved as a way
in which dolphins could meet the requirements of their challenging and ever-changing environment. Yet in captivity, with its
more stable and less challenging environment, dolphins exhibit the same collection of behaviors as those living in the wild.
A dolphin spends a majority
of its time and energy each day seeking out relationships. Its standing in its society is determined by its interactions with
other dolphins. As its group composition changes, its rank and social standing may change. In the wild dolphins live in what
is termed a fission-fusion society, meaning their group composition is constantly changing. The way in which these groups
form and reform is influenced by a variety of factors including gender, age, familial relationships and reproductive status.
Dolphins use sexual encounters (as many as 10 per day) as a means of affirming social relationships within their group.
The study of dolphins has revealed
specific behaviors are often associated with specific actions. An example of this is those behaviors associated with group
travel. A communication to begin travel is often initiated by breeching (jumping out of the water and landing on one’s
side). A communication indicating the travel is over is often done by upside-down lobtailing (rolling over to expose the ventral
side at the water surface, lifting the flukes above the water, and then slapping them down onto the water surface). Such communication
within dolphin groups has its rules, though. Only the dominant animals are allowed to demonstrate group control. In this example
of group travel, breeching is almost always performed by males; upside-down lobtailing is almost always performed by females.
After the nursing period (1-2
years), dolphins markedly reduce associations with their mothers and form long-term associations with other dolphins. Male
calves exhibit such disassociation more quickly than do female calves.
In forming new associations,
the Bottlenose prefers to do so with animals of its own gender. This is most likely due to the differences in reproductive
strategies between males and females. Females show less aggressive behavior between each other than do male dolphins. Male
fighting skills, often practiced between juveniles, may be necessary in order to be successful at some time in the future
in obtaining females with which to breed.
Aggressive behaviors may include
biting, teeth-raking, jaw-popping, fluke-slapping, head-butting and ramming. The outcome of aggression is dominance. Head-butting
is a particularly aggressive behavior between two dolphins. A male ramming a female, although an aggressive behavior, it is
usually associated with the initiation of sexual activity.
Juvenile males and females exhibit
social play. This play, similar to adult conflicts, may be practiced in order to provide the skill to respond to others and
to predict how others will respond to them when they are mature and off on their own. It is also through these repetitive
playful and aggressive behaviors that the social hierarchy and order of dominance are established. Dolphins rarely inflict
long-lasting physical damage on each other. This would be counter-productive as it would remove a member from their cooperative
Less aggressive behaviors such
as gentle contact and contact swimming provide bonds between animals. Gentle contact between animals includes using the pectoral
fin to pet or rub any body part of another dolphin. Contact swimming involves two dolphins synchronously swimming while one
animal lays its pectoral fin on the flank of the other. This unchanging contact and synchronous swimming then continues over
an extended period of time. Contact swimming is more often seen between females than between males. The prevalence of contact
swimming between females may be part of a female’s nature to provide, as a new mother, assisted locomotion to its newborn
(where the new calf swims rather effortlessly in its mother’s slipstream).
Dolphins demonstrate a type of "grief" (I use this term at the risk
of appearing anthropomorphic, or attaching human behaviors to animals) when family or pod members die. They often stop
eating, become lethargic, distance themselves from and don't associate with other dolphins and become unresponsive.
This behavior lasts for a few days, at which time they appear to recover and resume their typical activities, almost as if
forgetting the event occurred. This is true even when a mother's calf dies.