There is no sure method of attracting wild dolphins and it is best to wait and let the dolphins come to you. It appears that they are sometimes attracted to engine noises or following a diver on an underwater scooter. However if you are shooting underwater video, noises from boat engines or scooters affect the recording of the dolphin's whistle. Also the noise from the clicking and winding of student's disposable underwater cameras seemed to stir the dolphins' curiosity.
Once the dolphins choose to interact with you it is good to keep eye contact with them and try to follow them with gentle dolphin like movements. Reaching out with hands or touching dolphins is not recommended. It is important to realize that dolphins do not have long extensions protruding out of their bodies and these are therefore unfamiliar to them. There have however been several encounters where people could not resist stroking the belly of very calm dolphins who appeared to be enjoying it. As a rule though, it is best to refrain from such activities as no one has yet determined when the dolphins will react positively or negatively. There have been recorded incidents were dolphins have injured humans who handled them aggressively. The only known fatal injury occurred in Brazil when a man took advantage of the social nature of a dolphin by molesting it. The dolphin killed him.
It is best not to swim or stay with dolphins that are not interested. If dolphins are sighted and then approached it does not necessarily mean they are keen on playing with humans. Staying for extended periods of time (over one hour) with dolphins is also not recommended as they have their own daily responsibility, like feeding, mating and socializing that should not be interfered with. Dolphins are very complex social animals that should be respected at all times.
The ultimate goal of any dolphin admirer would be to fully understand its complex mind. It seems doubtful that this will happen for many generations, keeping the dolphin world something of a mystery to man.
functions of echolocation. The lower jaw of the dolphin curves outwards to serve as a sound conducting ear. The 'clicks' emmitted by the melon can be heard in the dolphins' lower jaws from several miles away.
The method of echolocation in dolphins is the same as the sonar used on boats to detect schools of fish or the ultrasound scanners used in hospitals to check unborn babies. The extraordinary sensory mechanism of echolocation allows dolphins to find flatfish and crustaceans completely buried in the sand. They can also catch fast-swimming prey in total darkness. The short and repetitive clicks, estimated at less than one millisecond in duration, can temporarily stun a fish, allowing the dolphin to easily grasp it. It was fishermen who first described the fishing methods of dolphins after seeing them effortlessly picking fluttering fish, which they had previously stunned, from the surface
Echolocation in dolphins is not the principal means by which dolphins communicate, except for the larger odontocetes, like the sperm whales, who use echolocation for communication and their clicks are longer and repeated less often. Dolphins communicate with their own language in the form of whistles. Studies of dolphin whistles within the same species revealed that different groups will have their own whistle dialect. Furthermore each individual will have a signature whistle or voice print that dolphin probably use to recognize each other. By digitalizing recordings from an underwater video camera into a computer, Dr. Denise Herzing has created an electronic dictionary of signature whistles of the Atlantic spotted dolphin (Stenella frontalis). Vocalization in dolphins is still, however, poorly understood and will require many more years of research.
The Atlantic Spotted Dolphin
Spotted Dolphin is the common name that best describes a dolphin which as an adult is speckled with dots. The degree of dots determines the age of the spotted dolphin and it is one of the only cetaceans that completely changes its color pattern from newborn to adult. There are five different phases of color changes. 1) Neonate (newborn) : newborn calves are dark gray with a white underside and have no spots. 2) Two-tone (infant): as the calf grows the color changes to two-tone, dark on top, light on the underside, and there are still no spots. 3) speckled (juvenile): dark spots begin to appear on the lower part of the body during the adolescent phase. 4) Mottled (young adult) : light spots begin to appear on the dark upper portion of the body; this may signal sexual maturity in the females. 5) Fused (adult): both white and dark spots merge to form various patterns. The tip of the rostrom (beak) becomes white with age, especially in the males.
Adult Atlantic spotted dolphins are approximately two meters in size and weigh up to 140 kg. They have been observed feeding in the shallow sandy bottom on flounders, razorfish and tile fish, but will also venture in the deeper Gulf Stream to catch squids and pelagic fish. The dolphin reaches maturity between 12 and 15 years and have a one year gestation period. As in most cetaceans newborns come out tail first and will feed on its mother milk. Other dolphins called "aunties," which may not be related to the mother's calf, will also take the responsibility of teaching young dolphins how to survive.
The interaction between dolphin and man which occurs in The Bahamas is unique in the world and therefore it is essential to establish proper management of the area to ensure that the dolphins will not suddenly disappear because of mans actions.