Communication

Description: Communication in bottlenose dolphins appears to be extensive and complex. A dolphin maintains an intricate social network that includes a few close associates (such as mothers and calves or pair-bonded males), plus more casual relationships with others that come and go within a larger group. Dolphins hunt together to find food. Pods of dolphins coordinate their movements to herd prey, then take turns swimming into the middle of the assembled fish to eat. There is still much to learn about how dolphins communicate.

Signature Whistles: Since water transmits sound so much better than air, dolphins rely on sending and receiving in-water sounds for communication more than any other mode. Each dolphin seems to develop a distinctive high-pitched whistle which scientists call a signature whistle and which serves as a means of individual identification. It may let the rest of the pod know who is around, where they are, and perhaps, something about their mental state. Dolphins in distress sometimes emit their signature whistles very loudly. Whistles may serve to establish or maintain vocal or physical contact between dolphins. Dolphins often respond to another dolphin whistling by whistling themselves or moving toward the whistler. If they become separated a young calf and its mother whistle frequently until reunited. Dolphins also whistle when separated from other group members.

Making Other Sounds: Dolphins are capable of imitating certain sounds very accurately and often learn other dolphins' whistles. One reason for imitating another dolphin's whistle may be to make contact with that dolphin and get its attention within a large group.  Dolphins may use other sounds besides whistles to communicate. Courtship behavior can yield pulsed yelps. When under duress, dolphins emit pulsed squeaks.   Aggressive confrontation can produce buzzing click-trains.  When a dolphin in the wild slaps its tail on the water, it is usually a sign of annoyance or a danger warning to other dolphins. Dolphin "friends" may swim along face to face touching flippers. They can also be seen swimming, twisting, and turning in perfect synchronization.

Dolphin courtship  behaviour includes twisting, nuzzling and tooth-scratching

The generally poorer visibility found underwater prevents dolphins from communicating visually over any distance. However, when close to each other, body language may play a role in dolphin communication. Below is a list of dolphin behaviors possibly used for visual communication.

Dolphin Body Language

Arch: Bend head and tail ventrally. Eye white display: Rolling eyes, showing the whites. Flex: ;Bend head and tail dorsally. Head wag: ;Rapid, side to side shaking of the head. Play dead: Roll over submissively in the vicinity of another dolphin. Snit: Sharp, sideways head jerk with closed or open jaws; may be accompanied by a sound *. (* May indicate agitation or agressive behaviour)

Dolphins living in association with humans pay a great deal of attention to human body language, as evidenced in observations of dolphins involved in research projects. During research sessions humans can inadvertently cue participating dolphins with even the most subtle body movements. Some dolphins learned to notice and read tiny, unconscious, and almost impossible to detect movements of the researchers that indicated the correct answer.  (This is called the "Clever Hans Effect," after a horse who lived around the turn of the century and supposedly figured out complicated math problems by stamping out the correct answer with his hoof. Careful observation of the horse by scientists showed that Hans was watching his owner's reactions and would stop stamping his foot when the owner relaxed. If Hans could not see his owner, he could not solve the math problem). Researchers take great care to keep dolphins from seeing any human who may know the right answer to a research question.

In a common behavior called a "breach",, a bottlenose dolphin jumps out of the water and lands on its side. This may be a display of strength

Communication By Touch

To some extent, dolphins may also communicate by touch. Calves swim close to their mother, brushing her body with their flanks and pectoral fins. This may serve to strengthen their bond and promote or strengthen social ties.   On the other hand, dolphins use touch in rough, aggressive ways during courtship and establishing dominance.   They use their teeth to make parallel scratches, called rake marks, on each other's skin.

Below is a list of behaviors that dolphins may use to communicate by touch.

Bite:;Close mouth around body part of another animal.* Butt: Hit with melon or snout.* Hold hands: 	Swim with pectoral fins overlapping. Mouth: ;Touch another animal with open mouth. Nuzzle: Touch or rub another animal with closed mouth. Pectoral Pat: Tap or stroke with pectoral fins. Push: Forcefully press against another animal with head or rostrum.* Ram: Hit another animal full force, head-on.* Rub: Two animals touch body parts, moving against each other with friction. Stranding on chest:   One animal inverted, lifting another out of water, putting recipient between the flippers (often between mother and calf) Stranding on rostrum: One animal lifting another out of the water, carrying recipient on the rostrum (often between mother and calf). Tail kick: ;Strike with tail.* Tooth rake: ;Draw teeth across the body of another animal.* (*May indicate agitation or aggressive behavior.)

For many years, researchers have looked for evidence of a dolphin language, a way to share complicated information such as stories, family histories, and philosophy in the way that humans do. Although a few dolphins have learned to use a simple artificial language consisting of hand gestures or computer-generated whistles, extensive research to date has failed to demonstrate a natural language in dolphins.