Imagine that you are scuba diving in the southern part of the Atlantic Ocean. As youíre busy exploring the ocean floor, you hear high pitched noises. You follow the noisesÖ they become louder and louder. Your heart races as you finally turn the corner of a sea cave. You seeÖ bottlenose dolphins!!! As you observe these playful creatures, you become more interested in them. When you decide to do some research about them, this is the information that you find.
One major fact that you find is that dolphins are mammals like you and me. This means that they breath air, and they grow hair. They are also born alive, and they nurse from their mothers when they are young.
One other fact that you find interesting is how long these creatures are. The bottlenose dolphin, specifically, is 3 m (10 ft.) This dolphin can weigh up to 400 pounds. Now thatís a big animal!
The dolphinsí body shape plays a big roll in the speed of the animal. The shape is narrow like a bullet or a torpedo. This feature in the dolphin helps it swim faster through the water. The dolphinís natural speed for swimming is 18-22 mph ( 29-35 kph).
The bottlenose dolphinís usual snack is shrimp, krill, sea plants, and other small fish. Hunting for this creature is a pretty simple task. Dolphins usually donít have to dive very far to catch their prey.
Dolphins usually hunt in pods. It is easier to hunt this way because when the dolphins surround whatever they are trying to catch, the animal thinks that the pod is one big fish. This frightens them, so they are afraid to even move a muscle. The dolphin can get a better hold on the fish itís trying to catch when it is scared to move.
Where the dolphin lives and catches its food is only the first few miles or kilometers below the surface. This zone is called the twilight zone. Other creatures that live here include whales, sharks, small fish, sea turtles, jellyfish, and octopuses.
Dolphins are very social animals. They always travel in large groups, called pods. These groups include up to 100 dolphins per group. They stay in groups this large because they depend on one another for helping to catch dinner and other daily needs. They also hate to be alone because they are so social. This means that they like attention from other dolphins.
Even though dolphins are very friendly animals, they have many enemies. Some of these enemies are tiger sharks, dusky sharks, bull sharks, and sometimes even orcas. When a dolphin can see that an animal is trying to prey upon it, the dolphin floats calmly, pretending itís dead. This makes the shark think that some other animal already killed it. The dolphin will be ignored because sharks only like to eat fresh meat.
When you hear the squeak of a dolphin, you automatically think that itís saying something. Well, thatís true! But they donít use their vocal cords to do that. The dolphin simply uses its blowhole. This works because the dolphin opens and closes the tiny hole. When the dolphin does this really fast, it creates the squeaky noise. The dolphin uses the air above the water to do this. Dolphins use the stored air in their blow hole to communicate under water. They can communicate above and under water.
Dolphins have very good eye sight. This is a must if you had to live under the sea. You must always be alert, just in case a predator is approaching you. This very good quality is probably caused by the diet dolphins eat. Dolphins eat so many fish that have tons of things that cause their eye sight to be so wonderful.
A dolphinís life span is pretty long compared to other animals. Marine biologist say that you can expect a dolphin to live up to 20 years old. A couple dozen dolphins lived to about the age of 50. Thatís a long life for a dolphin!
In the dolphin population, there is a wide variety of diseases that can kill a dolphin, with a painful death. Most of this is caused by bacteria from water pollution. The bacteria in the water can cause respiratory disorders, heart diseases, tumors, skin diseases, stomach ulcers, and urogenital disorders. All of these symptoms can be caused by polluting the water.
Right now, dolphins suffer from water pollution. This usually is caused by\ people dumping trash and chemicals in the ocean. This is only one of the many ways we can help our oceans become better than they are.
One other very big threat that dolphins face is fishing nets. The reason for this being so dangerous is the fact that if youíre not careful, sometimes you might just catch a dolphin in your fishing net. This will trap the dolphin so it canít swim up to the surface of the water to breath. This usually happens to lazy tuna fish companies.
When youíre finished with your research about the bottlenose dolphin, you head back to the same spot you first saw the pod of dolphins. This time you donít see dolphins, you see a strange looking creature. You finally remember what it is. Itís a Ö(J find out in my next report J )
Sea Research Foundation. Mystic Aquarium. www.mysticaquarium.org Date last visited: December 5th, 2000.
Dobbie, Beatrice. The Sea. New York: C.D. Jackson, 1961.
Earl, Silvia. Dive! New York: Scholastic, 1999.