Many people have a big fear of sharks, especially Great Whites. A lot of this comes from movies like Jaws - which is based on a number of attacks that really happened in New Jersey in 1916. Some people think that there are tons of sharks waiting to eat them if they venture out into the ocean, which is simply not true. Sharks rarely ever eat humans and are solitary animals. They either travel alone or in groups of two. Shark attacks are quite rare, in the US there are two to three non-fatal attacks on swimmers, surfers, and divers per year. By the number of reported incidents, Dogs kill more people each year than Great Whites have killed in the last 100 years. There are lots of divers who swim with sharks and are not attacked. In fact, there are places where you can be guided on a dive with sharks after just one dive lesson. They get used to people and get quite tame. Sharks are misunderstood animals.
Plylum Chordata
Class Chrondrichthyes
Order Lamniformes
Family Lamnidae
Genus Carchardon
Species carcharias
The white sharks are the largest predatory fish in the world. It is the only species of the genus Carcharodon that has survived the ravages of time. The rest of the species have gone into extinction.
The great white sharks are extremely sensitive to the electrical field emitted by the movement of living creatures. Their sensitivity is due to the extra sense that was given by the Ampullae of Lorenzini. The sharks are so sensitive that they can perceive half a billionth of a volt.
Sharks are important predators in the marine ecosystem. Their favorite prey are seals and sea lions. As juveniles they eat fish, and rays. When they become full grown they eat marine animals such as whales, seals, dolphins, large tuna fish, sea otters, and dead animals that they find floating on the surface. In order to catch its food a shark will go along the sea bottom and look for shapes at the surface. If it sees something similar to the shape of a seal they charge full speed. They ram the prey and give it a first bite all in one motion, which stuns and injures the prey. It then disappears and allows the prey to bleed to death. When it’s certain the prey’s dead it begins to feed. Sharks don’t chew their food, they just rip it into mouth-sized pieces and swallow it whole. A big meal can last a shark up to two months.
These sharks are ovoniparous, they give birth to 2-14 fully formed pups which are up to 1.5m (5ft) long. Fertilization of the eggs occurs in the female, and later the eggs actually hatch within the female. The young are nourished by eating unfertilized eggs and smaller siblings in the womb. There is no placenta with which they can get nourishment from their mother; they must fend for themselves. The female gives birth to live young, unlike many other sharks who lay eggs. The newborn gets no help from its mother. As soon as it’s born it swims away to begin living its life. A newborn is about 4ft long, and it grows 25cm (10inches) each year, reaching maturity at 10 years.
SHARK ATTACKS???
Great white sharks don't normally attack human beings unless provoked or human have been mistaken for food. During dawn is when the sharks come out to feed and sometimes they feed in musky waters. Surfers on their surf board looks like turtles from below and the sharks favourite food are turtles and seals.
Therefore to avoid being eaten by sharks:
- Don't go into open waters during shark feeding time as they go frenzy
- Don't go into open waters if you are hurt and have a wound, sharks can smell blood from quite far away
- Don't go into open waters with your pet
Think about it....
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