Who out there has heard the sounds of a dolphin under water???

Question

What did it sound like to you???

Answer 1

TYPES OF SOUNDS

Dolphin make many types of underwater sounds. The three that are most well-known are their whistles, clicks, and burst pulses.

Whistles

Dolphins produce many different types of whistles. One whistle which dolphins use most frequently, called a signature whistle, appears to serve as identification of individual dolphins since each dolphin develops a signature whistle that is uniquely its own. Dolphins do not appear to be born with a signature whistle. Calves develop their signature whistles over a four to six month period after birth. Each dolphin’s signature whistle pattern is distinctive, yet certain parts of the whistle stay constant while other parts of the whistle change with changing circumstances. This suggests that whistles may communicate other information or serve other purposes. Dolphins have an exceptional ability to mimic sounds and have been recorded making the signature whistles of other dolphins. The approximate frequency range of bottlenose dolphin whistles is 5 to 15 kHz.

Burst Pulse Sounds

Burst pulse sounds are a general classification given to such sounds as barks, mews, chirps, and pops. Dolphins apparently make these sounds only under emotional duress, when they are angry, frightened, upset, or frustrated. These sounds can be directed towards humans, other dolphins, and inanimate objects, as demonstrated by a dolphin who once destroyed a piece of research equipment while emitting intense burst pulse sounds.

Researchers have thought for a number of years that dolphins could stun or kill fish and squid with sounds they produce, having observed fish in dolphin pools swimming one minute and lying on the bottom the next. At first, researchers thought that dolphins used echolocation as the stunning sound, since dolphins are capable of echolocating very loudly (see below). Testing revealed that dolphins trained to echolocate powerfully at fish and squid did not stun them, so researchers began looking elsewhere for the stunning sound. Recordings of bottlenose dolphins and orcas in the wild have led researchers to now look at loud, low frequency sounds, possibly even burst pulse sounds, as the source of the dolphin's ability to stun prey.

Clicks/Echolocation

Click here for a diagram of echolocation

Clicks emitted by dolphins are thought to be exclusively used for echolocation, the dolphin's amazing ability to gather information about its world through sound. Clicks are produced in rapid sequence, called "click trains," that sound to us like a creaking door or loud buzz. The clicks are produced so rapidly, you have to have special equipment to hear just one of them. The frequency range for echolocation clicks is 0.25 to 220 kHz. Because lower frequency sounds travel further, dolphins tend to use lower frequencies when echolocating on objects that are at a the distance. Lower frequency clicks, however, do not deliver as much detailed information about an object as higher frequency clicks. Thus, as the dolphin moves closer to an object, it can increase the frequency of its echolocation to learn more about the object.

Dolphins have a waxy, lens-shaped structure in their forehead called the melon that focuses the clicks into a tight beam forward. When dolphins are examining an object or scanning their environment, their heads will move rapidly from side to side as they direct the echolocation beam back and forth across the object or through the environment. Dolphins may be able to accurately echolocate on objects as far away as 100 yards. They are able to create clicks powerful enough to fall into the finite region of sound; that is, any more energy put into the sound would turn into heat. However, dolphin echolocation is useless in air.

The clicks emitted by a dolphin strike objects in its underwater world and bounce back as echoes to be picked up through the dolphin's lower jaw. From the returning echoes, a dolphin can tell the size, shape, distance from, speed, direction of travel, and density of the object. Thus, dolphins can tell the difference between materials of different densities, even if they look the same. Dolphins are particularly good at detecting air spaces within objects. Since most fish have a swim bladder filled with air to maintain the fish's equilibrium, dolphins can easily detect fish with their echolocation. Dolphins have an exquisite anti-jamming ability associated with their echolocation. Even in a large group of dolphins all echolocating at once, each dolphin seems to be able to pick out its own echolocation echoes and not collide with another.

Interestingly enough, scientists now speculate that a dolphin’s teeth may play a part in receiving incoming echolocation pulses. The teeth are perfectly spaced one tooth space apart than each other, and the teeth on one side of the jaw are aligned one half of a tooth space forward than the other side of the jaw. It is believed that this arrangement of the teeth acts as an array or antenna focusing the incoming sound, and helping the dolphin pinpoint the exact location of an object.

Dolphins do not echolocate constantly, especially if they are in a familiar area or if the visibility is quite good. When not echolocating, dolphins rely on their extremely sensitive hearing for information about their environment, including sounds made by other dolphins. Dolphins can control the loudness of their echolocation clicks, adjusting this based on their surroundings and how far they want the clicks to travel. The concern that dolphins living in aquariums with concrete walls may be harmed by the sounds of their echolocation bouncing off the walls is completely unfounded.

http://www.dolphins.org/Learn/lmm-acou.htm#Types

Answer 2

a series of clicks (snorkling in Maui)