Introduction. How do Dolphins hunt? What are Dolphins? What do Dolphins eat? Dolphins hunt using different methods. These methods

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1 Introduction... 2 What are Dolphins?... 2 What do Dolphins eat?... 2 How do Dolphins hunt?... 2 Brain of a Dolphin... 3 Structure of the brain Dolphins lives... 4 What are their lives like?... 4 Dolphin Behavior... 5 How do dolphins behave?... 5 Reproduction... 6 How Dolphins Help People... 7 How fast can Dolphins Swim?... 7 What types of other animals eat Dolphins?... 8 Attraction to Dolphins... 9 Climate Dolphins live in... 9 How to Protect Dolphins...10 The purpose of the hole on top of Dolphins body...10 Word search...12 Page 1 of 12

2 Introduction What are Dolphins? Dolphins are aquatic mammals that are related to porpoises and whales. There are three different families: Delphinidae (oceanic dolphins), Platanistodidea (oceanic and river dolphins), and suborder Odontoceti (toothed whales). There are 40 species of dolphins; the size varies from 4 ft. up to 30 ft. and 10 tons (the Orcha). These species weigh about 110 to 440 Ibs. What do Dolphins eat? Dolphins eat a variety of different foods. Some dolphins eat fish, for example herring, cod, and mackerel. Some dolphins eat squid. Orchas may eat other marine mammals, such as sea turtles or sea lions. How much dolphins eat depends on the type of fish they eat. If the dolphins eat a fish that has a lot of fat, they won t eat as much. How do Dolphins hunt? Dolphins hunt using different methods. These methods Page 2 of 12

3 are known as herding, whacking, stunning, corralling, and foraging. The first method dolphins use is herding. Dolphins will work together to surround a school of fish and take turns swimming through catching as many fish as they can. Whacking is the process where dolphins strike fish with their tails, stunning the fish, so that the dolphins could eat them. Stunning is where dolphins send a very LOUD click throughout the water. The loud noise will shock the fish and leave the fish in a stupor, unresponsive. Corralling is when dolphins herd a school of fish into shallow water making it hard for the fish to escape. Lastly, foraging is when dolphins pick up a sponge and use it to push through the mud at the bottom of the shallow parts of the ocean looking for food. Brain of a Dolphin Structure of the brain. The Dolphins brain has two sections, each with two lobes. The blood flow of the brain Page 3 of 12

4 has a separate blood supply. In fact, they can even be considered to be completely separate brains. When dolphins sleep, one of the sides of its brain completely shuts down while the other stays alert in order to run body functions. The dolphins eyes are connected to different sides of the brain. A dolphin can still see while it is still sleeping, making it difficult for predators to sneak up on them. Dolphins lives What are their lives like? Dolphins are social mammals. They like to enjoy company of other dolphins. Dolphins most often live in pods, little communities, or schools. When there is a lot of food available, dolphins group up even larger, called superpods. Superpods can have more than 1000 dolphins in it. Dolphins also swim with larger mammals, such as whales and even humans. They will also sail next to ships across the ocean. Page 4 of 12

5 They develop great friendships with one another. If a dolphin is injured, fellow dolphins will group around it and care for the injured dolphin. Dolphins haven been known to protect injured people who are attacked by sharks. Dolphin Behavior How do dolphins behave? Dolphins are known for their alertness and playfulness behavior. This makes them a favorite for wildlife watchers. They will leap out of the water vertically viewing their surroundings. Scientists believe dolphins conserve energy by swimming alongside ships, this practice is known as bow-riding. Dolphins communicate using echolocation to find prey and to hunt together. Dolphins will follow seabirds, fishing boats, and whales to feed on the fish they scare up or discard. Page 5 of 12

6 Reproduction Dolphins mating season is throughout the year, some areas, however, are during the spring and fall. The female will carry the calf approximately 9 to 17 months depending on the species. When it is time for birth, the female dolphin will go near the surface of the water, distancing herself from the pod. Numbers of offspring dolphins have are usually one calf, twins are rare. As soon as the calf is born the mother immediately takes the calf to the surface so that the calf can breathe for the first time. The calf will stay with their mother no longer than 8 years old. Page 6 of 12

7 How Dolphins Help People Since ancient Greece, dolphins have helped many people. For example, dolphins protect people in the ocean from shark attacks. They do this by swimming around the person and attacking the shark. Boats follow dolphins during thick fog conditions until the fog clears up. How fast can Dolphins Swim? Page 7 of 12

8 Dolphins can swim at speed up to 25 miles per hour when they are in a hurry to get somewhere. When dolphins swim for normal tasks, they swim at speeds 7 to 8 miles per hour. What types of other animals eat Dolphins? Large sharks will eat small species of dolphins or eat calves (baby dolphins). Occasionally, killer whales eat small species of dolphins as well as larger sharks. Larger species of dolphins are apex predators. This means that they are at the top of the food chain. Page 8 of 12

9 Attraction to Dolphins Humans are attracted to dolphins by their grace and beauty, their jumping skills, and how they resemble children playing. Another factor that humans are attracted to dolphins is that dolphins are very intelligent in the animal world. Climate Dolphins live in Different species of dolphins live in different climates. From the cold waters of the north pole, where killer whales can be found, to tropical waters of the Caribbean, where the bottlenose dolphins lives. Page 9 of 12

10 How to Protect Dolphins There are several organizations which are devoted to help and protect dolphins. Unfortunately, they have no further influence than exposing the cruel act made by organizations and humans against dolphins. Organizations you can find are the Whale and Dolphin Conservation Society, Hong Kong Dolphin Conservation Society, Green Peace, the Mediterranean Dolphin Conservation, and many more. The purpose of the hole on top of Dolphins body The hole on the top is called the blowhole. Page 10 of 12

11 Dolphins breather through the blowhole, which empties and refills the lungs of a dolphin. The blow is explosive and the air reach speeds of up to one hundred miles per hour. Dolphins have a nerve mechanism that alerts them when the blowhole is out of the water so they can blow the old air out and take in new air. Strong muscles close the blowhole when dolphins dive into the water to avoid drowning. Page 11 of 12

12 Word search Dolphin Herding Whacking Stunning Corralling Foraging Brain Mammals Superpods Alert Playful Calf Page 12 of 12