Our Animals > Dolphins
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Atlantic Bottlenose Dolphins (Tursiops truncatus) Click image for larger view

Fun Facts

• They typically grow to 7-10 feet in length and weigh between 300-500 pounds.
• A blubber layer keeps them warm, and stores nourishment for use when
  food is scarce.
• Dolphins steer with their pectoral fins and propel themselves through the water
  with a lobed tail called a fluke.
• Dolphins can swim 18-22 mph for short bursts, but usually cruise at 5-7 mph.

Distribution

Atlantic Bottlenose Dolphins inhabit temperate and tropical waters, and are found in the United States from Cape Cod through the Gulf of Mexico. The Mississippi Sound
is home to the largest stable population of Atlantic Bottlenose Dolphins in the world. This is due in part to its warm, protected waters.

Food

Dolphins are carnivores, which means they eat other animals - mostly fishes and squids. But they have different diets depending on where they live. For example, the white-sided dolphins of the Pacific Ocean enjoy munching on salmon and anchovies, while the white-beaked dolphins of the North Atlantic are fond of a fish called capelin.

Social Structure

Dolphins tend to be very social animals, swimming in social groupings called pods. These groups, however, are very flexible and fluid, not at all like the social unit we refer to as a family.

Sounds and Echolocation

Most sounds that dolphins make are produced in their nasal cavities below their blowholes, not their mouths. They can make a wide variety of sounds based on how they move air through the muscles and folds in their sinus passages.

Dolphins possess an ability known as echolocation. The dolphins produce directional clicks that are focused through fatty tissue in the dolphin’s forehead known as the melon. The sound waves travel out in front of the dolphin and bounce off of objects in front of the dolphin. The echo returns and is received through an oily, fat-filled canal in the dolphin’s lower jaw. Then it is carried on to the dolphin’s brain. The brain interprets these echoes to determine size, shape, speed, distance, direction, and even density of objects in the water. Dolphins use echolocation to find food, to navigate, and even to determine the position and direction of its pod.