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Home , Cookiecutter shark, Goblin shark, Helicoprion, Isistius, River shark, Skerry

By: Caroline Bell

Table of Contents

Introduction………………………………………………………………………..3 of …………………………………………………………………...4 Shark Behaviour…………………………………………………………………...7 Shark Attacks……………………………………………………………………..10 Shark ………………………………………………………………….....13 Prehistoric Shark………………………………………………………………….15 Sharks Influence on the World……………………………………………………17 Conclusion………………………………………………………………………...19 Works Cited ………………………………………………………………………20 Images Cited………………………………………………………………...…….22

2 Introduction

Last summer I was watching Shark Week on Discovery , when sharks as an expert topic clicked in my mind. At the time, I was more interested in one of my other topics, and I thought that sharks would be a last minute topic. Then, after doing some preliminary research, I noticed sharks were being treated badly and I was interested in knowing more and helping to save them. At first I asked myself; why are people afraid of sharks? Then I realized the bigger question; why are people hurting sharks? Since then I have discovered that people injure these predators because they are afraid of them. I have also learned that sharks benefit our world and without them our Earth would fall apart.

3 Species of Shark

Some sharks are so weird looking, it is hard to peer at them. Megamouths are rare and incredibly bizarre-looking. These sharks get their name from their four foot wide, strange looking mouth. They are the smallest filter-feeders of all at only sixteen feet long. Since 1976 there have only been thirty-five megamouth sightings. It is hard to find out more about these gentle giants, but scientists do know they are unbelievably weird. Goblin sharks definitely earn their name. Even though goblin sharks are only about ten feet in length, their snout is about three feet long. These sharks protrude their jaws from their heads to catch and trap prey. Their teeth are long and sharp, a little like the ’s teeth. Sadly, they have rarely been seen alive. Goblin sharks are the freaks of the weird shark world. Cookie Cutter sharks have a bizarre way of hunting. These sharks use their as suction cups to attach to other . Once attached, the Cookie Cutter shark will bite and move around in a circle. The bite of this shark is almost a perfect circle. They bite into whales, dolphins, seals and occasionally . Cookie Cutter sharks are a little eerie to look at, but they are small and their bite is not deep enough to hurt an extremely. There are some sharks that individuals know little about, but there are also some sharks that people know well. Great White sharks are one of the most well - known sharks, probably because they are usually the shark that is seen attacking

4 people. The “great” in Great White is given to these sharks to describe their sheer size and power. Another name for this shark is the White Spinner or White shark. They can leap straight out of the water from below to surprise their prey. These sharks mostly eat seals, , dolphins, and occasionally other sharks. Great Whites are big with many teeth, but attacks on humans are still rare. The Great Hammerhead is one of the most identifiable sharks. These sharks will use their big heads to pin down their prey to the seafloor. They eat small fish, stingrays and . This shark's big head and its slightly tall, slightly curved are keys to identifying the shark. “No one shark is the same,” said EyeWitness Books, and that is illustrated well in the Great Hammerhead. Lemon sharks are one of the most common but not well-known types of sharks. They live in warm coral reefs. These sharks hunt and swim at night and rest during the day. Their yellowing color gives a its name. They eat fish, small sharks, squid, seabirds and . Lemon sharks are calm, social creatures and it is not likely for a Lemon shark to attack people. There are many different kinds of sharks now endangered all over the world. Blue sharks are one of the many species of shark that are at a low risk of becoming endangered. These sharks get their name from their indigo coloring. Like many sharks, the Blue sharks numbers are decreasing because of overfishing. Meat and fins of the are also eaten. Their skin is used for leather products. Blue sharks are beautiful creatures so it is sad to see them at risk of going endangered.

5 Sand Tiger sharks are at a high risk of in the wild. These sharks reproduce slower than they are being killed. Sand Tigers, also known as the Ragged Tooth and Gray , live over sixteen years in the wild. They are also considered vulnerable like the Blue shark. People catch these sharks for their ragged teeth, which give them their other name, for jewelry and a keepsake. Sand Tigers are now protected in many states but are endangered in the wild. Angel shark numbers are declining because of and overfishing. These sharks have been caught in bycatch and usually end up dead. They cannot be found in their old habitats, because they have been chased out by fishing. Many different kinds of Angel sharks are in immediate danger of going extinct. used to catch these sharks for food. Angel sharks are protected in many places, but are still critically endangered. Many sharks are going endangered and knowing more about them can save them.

6 Sharks Behavior

Not all sharks sleep, but when they do they sleep with their eyes open and are aware of their surroundings. Some sharks experience short resting periods, others do not. Shark behavior is still being studied by scientists. Sharks can be predictable, but they are wild animals, and scientists do not always know what they are thinking. It has been said sharks are unintelligent, but studies show they are actually very intelligent for their small sized brain. Sharks are unpredictable, but usually it is easy to observe their behavior and how it changes to find out what they are thinking. Circling is an example of hunting behavior. The shark will circle its prey from below for the element of surprise. While slowly closing the circles, the shark will become more hostile. After circling, the shark will start to criss-cross toward its prey. When the time is just right, and the prey is least expecting it, the shark makes a violent attack. By studying these behaviors, humans can be safer by avoiding contact and interaction with circling sharks. There are more hunting ways than just circling. Some types are filter-feeding, tearing, or swallowing their prey whole. Filter-feeding is most common in bigger sharks that eat smaller animals like krill. These sharks have small -rankers inside their mouth. Water flows into the mouth and through a

7 filter-like structure called gill-rankers to catch the krill and microscopic sea creatures in the water. Tearing is the most common way of hunting for sharks like the great white and tiger shark. To begin, the shark will take a test bite to see if it likes the food. If the shark enjoys its catch, then it will tear meat bit by bit off the prey’s skeleton. The first couple of bites usually injure the prey so they cannot escape out of the shark's jaws. This is also one of the most violent ways sharks hunt their prey. Swallowing their prey is not the most common way of hunting, but there are multiple types of sharks that have adapted to swallowing their prey whole such as the Mako. Instead of going up to the prey and taking a test bite, the shark will swim at the victim and eat it in one bite. These three feeding strategies are used depending on the shark. A feeding frenzy is when many sharks get over-excited and eat anything, including each other. Feeding frenzies are dangerous to be around and can occur when many tiny bits of food are floating around in the water, and, one by one, sharks notice and start to go deranged. They can be dangerous for any animal in the area. Even bigger sharks will avoid getting involved in a frenzy involving smaller sharks.

8 It has been said that sharks have a sixth sense for hunting. This is the electrical sense. All animals give off an electrical field. Sharks have tiny pores on their snout called which allows the shark to pick up these electrical waves through the water. This lets the shark know which animals are injured or sick and which ones are strong and healthy. Naturally, the shark will go for the easy prey, the sick or injured prey. This sixth sense is incredibly effective. Not accidentally, some sharks travel in groups. These groups can include more than 100 sharks. Sharks can show cooperative behaviour within their packs. They work together to do things, like move a whale. The dominant sharks of their group will often nip smaller ones to get to the middle of the group. Not all sharks travel or hunt in packs. Sharks like the hammerhead prefer to travel in groups, while sharks like the great white favor hunting and traveling by themselves. There are many acts that show social behaviour between sharks. Smaller sharks sometimes dominate the bigger ones, usually over food. Nurse sharks, also known as the “lazy shark,” are known to be the most social shark. Many sharks are incredibly social between themselves.

9 Shark Attacks

Not only does Florida have the highest number of shark attacks in the US, but it holds 25 percent of the world's attacks. Since so many people visit Florida for vacation, it has higher chances for an attack to occur than anywhere else in the US. There are 130 worldwide shark attacks a year. In 2018, there was only one fatal attack out of 20 in . South Africa has, on average, only two attacks a year despite all the species of shark living there. This is because more people are in the water for longer and the sharks eventually move on noticing they are not getting a meal. has the second most shark attacks in the world. This is not surprising considering that Australia is home to 170 species of shark. The country with the most worldwide attacks is the US. Shark attacks happen in many places, but are still incredibly uncommon. Chances of being a victim of an attack vary between the types of activities the person is doing. Scuba divers have a five percent chance of being injured by a shark, most likely because they are out in open water and more vulnerable to attacks. From below, snorkelers look like prey to a hungry shark, which is why they have a six percent chance of being bitten by a shark. Swimmers swimming in the ocean have a 30 percent chance of being attacked by a shark because they flail around like an injured fish. Sixty percent of attack victims are suffers because, atop their board, they look like a seal, sharks' favorite food. It is not likely to be a victim of an attack, but it can happen. Shark related deaths can vary each year. In the US, only about one person dies from an attack out of 50 to 55 a year. In 2017 there were no deaths related to a

10 . In 2018 there was only one fatal shark attack. Living in the US, there is one out of 256 million chances of dying from a shark attack. There is a better chance of dying from a lighting strike or a vehicle crash than dying from a shark bite. The behavior of the shark during the attack varies between species. In only five percent of attacks does the shark bite multiple times. Most “attacks” are more one or two bites of the victim. Because of this there is a better chance of survival. Attacks are usually the result of a hungry shark mistaking a human for a fish. Many sharks are harmless and will not hurt a human. One inspiring survival story is that of Bethany Hamilton. Bethany Hamilton was attacked at the age of 13. The attack happened on October 31st, 2003 when Bethany went for an early morning surf at Tunnels , Kauai. Bathany lost her left arm in the attack. No one was sure Bethany would ever surf like she wanted to again. Despite what everyone said, Bethany Hamilton started surfing only three weeks after the attack and has not stopped. Krishna Thompson is not well known but has quite the survival story. Krishna was 36 years old and taking an early swim on a morning of his 10th wedding anniversary trip with his wife when the attack happened. The bite was in the waters off Freeport, Grand Bahamas. After the shark mangled his leg he was rushed to the hospital, unconscious from shock and blood loss. Krishna’s leg was amputated below the knee. The doctors say, “he is lucky to be alive,” Knowing that Krishna was lucky to be alive, he proved the doctor no matter how bad the bite,

11 you can survive it. These stories are inspiring and encourage younger kids to keep going even when things get hard.

12 Shark Habitats

Sharks can be found many meters down, deep in the ocean, as far as 2000 meters down (6561 feet). These deep-dwelling sharks only come to the surface at night. The sharks that live deep in the ocean are hard to study, but scientists are coming up with better ways to do so. Sharks are found in almost all bodys of water. Multiple shark species live in the open waters of oceans or seas, mostly in warmer waters. Some species live near reefs and rarely come to the . Specific sharks are able to survive in rivers or freshwater, where they migrate with their food. The and the Ganges are two shark species that can survive in rivers. These sharks have extra to help transfer from saltwater to freshwater. River sharks are rare. Bull sharks are one of the few shark species that can go from saltwater to freshwater. Bull sharks are considered more dangerous because they live in both freshwater and saltwater and are more likely to come in contact with humans in freshwater. The Bull shark is next to the Great White in the dangerous shark species group. Bull sharks can swim miles up rivers and are known for attacking people and their taste for freshwater. Even though bull sharks are considered incredibly dangerous, attacks are rare and it is not likely to come in contact with one. Many species of shark live in the waters around North America. Sharks like the because currents such as the Stream pushes warmer water

13 into the Atlantic. Sharks that live in the Atlantic include the tiger, whale, blue, megamouth, thresher and great . The Megamouth is the rarest shark in the Atlantic, and the fastest shark is the Mako. Not all sharks in the oceans of North America are dangerous, such as the Angel shark. However the most dangerous sharks are the bull, great white and hammerhead shark. Dusky sharks have the strongest bite out of the North American sharks. Knowing about the waters that contain sharks, humans can be more prepared for a beach day.

14 Prehistoric Sharks

The megalodon was one of the biggest sharks ever. The word “megalodon” means “big tooth”. The megalodon was also known as the “meg”. Living six million years ago, the megalodon was about 52 feet long. That is four times the size of the great white. The megalodon’s jaw alone measured around six feet wide. Its teeth were the size of bananas. The megalodon was the biggest shark ever recorded. This shark's name suits it perfectly. The megalodon went extinct two million years ago and no one knows exactly why. Scientists are still debating whether the megalodon was an ancestor of the great white or not. Since scientists only have megalodon teeth, it is harder to research. The megalodon ate many animals including whales, seals, dolphins, giant fish and giant squid. It would use its teeth to slash into its prey. The megalodon would attack animals much bigger than themselves. It was a more aggressive shark and would not be afraid to attack a human. This means that if a human was around a megalodon, the megalodon would most likely attack the human. It is a good thing the megalodon has been extinct for millions of years. was the of prehistoric sharks living 270 million years ago. Its snout was more pointy than other prehistoric sharks. Helicoprion had a pattern similar to a tiger shark that was stripped or spotted. Helicoprion was quite the weird-looking shark. Helicoprion had a very distinct mouth. Helicoprion had a saw the size of a dinner plate on the floor of its mouth for a jaw. The saw was known as a spiral-shaped whorl. Helicoprion was the only shark known to have something like

15 a whorl on its body. Helicoprion ate mostly one animal, the mollusk. Helicoprion’s whorl could crush the of the mollusk or slice the mollusk. Helicoprion had a big taste for mollusk. Stethacanthus was a weird-looking shark. Stethacanthus lived 320 million years ago. It was about three feet long with a flat dorsal fin that has been described as a hair brush sticking out of its back. The reason for this is because the dorsal fin was covered in bristly scales used to fight off predators. Stethacanthus also had a pad of bristly scales on its head. This pad was used in many ways. When opposing each other, stethacanthus’s head pad looked like a scary face. This frightened predators. Sadly stethacanthus was eaten to extinction, but its dorsal fin and head pad were quite unique.

16 Shark Influence On The World

Everything that is alive is connected by the food chain. Most animals belong to more than one food chain. Ecologists call every link in the food chain a feeding level. An animal in a level higher than another does not mean the one higher in the chain eats the one lower in the chain, but means it has a bigger impact if something were to happen to it. Animals belong to multiple food chains because they eat

various species of animals. A food chain is used to place animals in categories to learn more about them. Sharks are impactful at the top of the food chain. Sharks will go after sick or injured prey that is easier to catch. By doing this, sharks are keeping the oceans clean. Without sharks many species will reproduce too much and cause an overload of the species. With too many animals of one species they will eat a whole other species then die of starvation because they have no other food. Sharks influence the world mostly through the food chain. Humans are a bigger problem to sharks than sharks are to humans. Humans kill about 100 million sharks a year, most of which are intentional. Sharks reproduce slower than they are being killed. Humans cause about 25 percent of

17 shark attacks by poking sharks, yanking their tails, and even trying to ride them. Spearfishing causes blood, fluids and electrical disturbances in the water which grabs the sharks attention. Sharks are killed for sport and competition. Humans play a major part in shark endangerment, which needs to stop. Sharks are critically endangered because of finning. Humans fin sharks for shark fin soup. In the process of finning, the shark's fins are cut off and the shark is thrown back into the ocean to save room in the boat for more fins. Many shark species numbers are declining because of shark fin soup. The fin in shark fin soup is added for tradition and texture. Even though shark fins have no taste or nutrition, people love them in their soup anyway. Without sharks our oceans will die. If sharks go extinct, then species of fish like the parrot fish will eat the coral reefs and destroy our oceans. Without sharks algae would overgrow and clog fish gills. The algae would also contaminate our seafood and water. Without sharks, their prey would no longer have to go somewhere to seek shelter against predators and they would eventually make their way to humans and might be dangerous in the water depending on the fish. Sharks have a big influence on our ecosystem.

18 Conclusion

Sharks help keep our oceans clean and by knowing more about sharks, we can help. Researching sharks has given me the chance to see what I and other people are doing wrong that is hurting and damaging our oceans along with the planet. It also gave me the chance to see how researchers and specific organizations like the Wildlife Conservation Society are working to protect the globe. Throughout my research I have become interested in how sharks have evolved and how they have adapted to their environments. I hope to continue learning more about how these creatures and how to help save them.

19 Works Cited

Bell, Samantha. Tiger Sharks. Cherry Lake Publishing, 2014. ​ ​ Dk Findout. December 2, http://dkfindout.com. ​ Encyclopedia Britannica. December 10, ​ https://www.britannica.com/animal/shark.

Fournoy, John. Shark Diver . 12 Jan. 2020. ​ ​ Gale In Context: Biography. January 10, ​ https://www.gale.com/c/in-context-biography.

How Stuff Works. December 8, animals.howstuffworks.com. ​ IUCN Red List. January 15, https://www.iucnredlist.org. ​ Kelly, Emily. Senior Aquarist. 10 Jan. 2020. ​ ​ Macquitty, Miranda. Eyewitness Books: Sharks. DK Publishing, 2008. ​ ​ McKeever, William. Emperors Of The Deep. Harper Collins, 2019. ​ ​ Musick, Dr. John. Faculty Emeritus. 5 Jan. 2020. ​ ​ National Geographic. December 24, nationalgeographic.com/search?q=sharks. ​ Sharks Info. December 9, http://sharksinfo.com/. ​ Simon, Seymour. Sharks. Harper Collins, 2006. ​ ​

20 Skerry, Brian. National Geographic Kids: The Ultimate Book Of Sharks. ​ ​ National Geographic.

World Book Online. January 5, worldbookonline.com. ​ Young, Karen. Shark Quest. Learner Publishing Inc., 2019. ​ ​

21 Images Cited https://australianmuseum.net.au/learn/animals/fishes/smalltooth-cookiecutter-shark --brasiliensis/ https://www.thoughtco.com/blue-shark-facts-4174680 https://www.smithsonianmag.com/smart-news/heres-why-sharks-prefer-salt-water- 180953985/ https://www.stillstoked.com/inspire-me/bethany-hamilton-inspires-girls-to-charge-i n-new-film-project/ https://greatlakesecho.org/2015/07/23/great-whites-in-the-great-lakes-bull-shark/ https://www.worldatlas.com/articles/what-are-helicoprions.html https://www.britannica.com/science/food-chain https://ipolitics.ca/2018/02/09/shark-finning-bill-passed-unanimously-committee- moves-senate/ https://phys.org/news/2019-01-tougher-baby-sharks-daddy.html https://www.dreamstime.com/photos-images/circling-sharks.html

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