Hammerhead Sharks By Jonathan Ibañez

Hammerhead Shark Species and Their Lengths Great Hammerhead- This species is the biggest of all Hammerheads and they can grow to be about 20 feet, but they are about 12 feet long on average. Smooth Hammerhead- This species is also very large and usually grows to be about 13 feet. Scalloped Hammerhead- This species of hammerheads can grow a little more than 13 feet. Scalloped Bonnethead- This species is extremely small and grows to a maximum of 3 feet. Winghead Shark- This shark has a long wing shaped head and is a medium sized shark with a a maximum length of 6 feet.

Hammerhead Shark Species and Their Lengths (Continued) Bonnethead shark- this shark can reach a maximum length of about 5 feet and they have a narrow, shovel-shaped head. Smalleyed Hammerhead- this shark can reach a maximum length of about 5 feet and have a broad, mallet-shaped head with a deep indentation in the center. Whitefin Hammerhead- This species of sharks can grow to be 9 feet long and have a wide head with thin blades. Carolina Hammerhead- Discovered in 2013 can grow to be 13 feet just like the scalloped hammerhead, but has 10 fewer vertebrae.

Hammerhead Shark Habitats Great hammerhead sharks live in warm temperate and tropical waters in the Atlantic, Pacific, and Indian Oceans. They migrate to cooler waters in the summer. Great hammerheads may be found in both nearshore and offshore waters. Smooth hammerhead sharks live both inshore and offshore, and on continental shelves in the western and eastern Atlantic and Pacific Oceans. They are found along the East Coast of the U.S. to the Caribbean, and from northern California to South America, off Hawaii, they have even been seen in freshwater in Indian River, Florida. Scalloped hammerhead sharks may be found in inshore areas out to deep water up to about 900 feet. They are found in the western Atlantic Ocean and in the Pacific Ocean from ,and Hawaii. They are also found in the eastern Atlantic Ocean, in the Red Sea, Indian Ocean, and western Pacific Ocean.

Hammerhead Shark Habitats (continued) Scalloped bonnethead sharks live in tropical waters of the East Pacific Ocean from Mexico to Peru. Winghead sharks live in shallow, tropical waters in the Indo-West Pacific from the Persian Gulf all the way to the Philippines, and from China all the way to Australia. Bonnethead sharks are in subtropical waters in the Western Atlantic Ocean and in the Eastern Pacific Ocean. They live in shallow bays and estuaries. Bonnethead sharks like water temperatures over 70 degrees F and make seasonal migrations to warmer waters during the winter months. Smalleye hammerheads are found off of the eastern coast of South America. Whitefin Hammerhead sharks are found in tropical waters in the eastern Atlantic off the coast of Africa.

Hammerhead Sharks Diets Great Hammerhead sharks usually eat at sun down and eat stingrays(Seems to be their favorite food), invertebrates, and fish, that even includes other great hammerheads. Smooth Hammerheads eat fish, sharks, skates, rays and invertebrates. Scalloped Hammerheads eat bony fish, sharks, rays, and invertebrates. Scalloped Bonnethead sharks eat crustaceans, gastropods, bivalves, cephalopods, echinoderms and fish. Winghead sharks eat bony fish, and invertebrates, including cephalopods. Bonnethead sharks eat primarily crustaceans (especially blue crabs), small fish, bivalves, and cephalopods.

Hammerhead Reproduction Great hammerhead sharks may mate at the surface, which is unusual behavior for a shark. During mating, the male sends sperm to the female from his claspers. Great hammerhead sharks are viviparous, which means it gives birth to live young. The gestation period for a female shark is about 11 months, and 6 to 42 pups are born live. Smooth hammerheads are sexually mature when they reach 8 years old. They are also viviparous. There are 29-37 pups per litter and are 19-24" when born. Young sharks sometimes form large schools, and may migrate north to cooler waters in the summer. These sharks are thought to live for 20 years or more.

Hammerhead Reproduction (continued) Scalloped hammerheads gather in large schools for breeding. Females give birth in shallow waters in summer. This shark species is viviparous like all other hammerheads. The pups are about 1.5 feet long when born, and 13- 31 pups are in each litter. According to FishBase, the oldest scalloped hammerhead that has been reported is 35 years old. Scalloped bonnethead sharks are also viviparous. The pups are about 9 inches long when born, and these sharks are thought to have 2 pups per litter. Winghead sharks are viviparous,give birth to live young, and they give birth after an 8-11 gestation period. Six to twenty-five pups are born in each litter. The pups are about 1-1.5 feet long when born.

Hammerhead Reproduction (continued) Bonnethead sharks are found in groups by gender as their season approaches. These sharks are viviparous and give birth in shallow waters after a 4-5 month gestation period, the shortest known for all sharks. The embryos are nourished by a yolk sac placenta thats attached to the mother's uterine wall. During development inside the mother, the uterus becomes separated into compartments that house each embryo and its yolk sac. Four to sixteen pups are born in each litter and are about 1 foot long and weigh about half a pound when born.

Hammerhead Shark Attacks on Humans Hammerhead sharks are generally not dangerous to humans, but great hammerheads should be avoided due to their great size. From the years 1580 to 2011 Hammerheads were responsible for 17 non- fatal, unprovoked attacks and 20 fatal, provoked attacks. Hammerhead sharks in general are listed by the International Shark Attack File as #8 on its list of species responsible for shark attacks. Even though they are for the most part harmless you should always keep distance. This kayaker had to fight a hammerhead because it continued to attack its kayak. http://www.cnn.com/videos/us/2015/09/22/kayaker-fights- hammerhead-shark-video-pkg.kswb

Seized: 100 Endangered Sharks Sold for Food In horrifying food news: Photos emerged this week of nearly 100 endangered scalloped hammerhead sharks for sale at a fish market in Sanya, in southern China’s Hainan Province, according to Chinese media. An outraged passerby posted photos of the animals on Chinese social media. The sharks were being sold for 15 yuan ($2.31) a pound. Scalloped hammerhead sharks can be found in temperate and tropical waters all over the world. They get their name from the scalloped shape of the front edge of their unique head structure. An international treaty, which China is a signatory to, restricts trade in the species. Despite this protection, the sharks are widely exploited to meet demand for their meat and shark fin soup, which is considered a delicacy in China. Local authorities seized the hammerheads. They’re still investigating the case, but have said that the fishermen didn’t realize the animals were protected.

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