Shark - this is perhaps the most perfect predator of the water element, which is considered the master of the oceans.But lately people to satisfy their whims and different economic needs, is merciless trapping and destruction of these fish.This can lead to an inevitable violation of ecology and a significant decrease in the number of sharks, and have a negative impact on the marine flora and fauna.To avoid this, now, many countries impose a partial or total ban on fishing for them.
sharks
Asked how many shark species exist in nature, it is impossible to accurately answer.Despite the fact that people consume them in large quantities, there are more than 400 species of fish, but it is only those that are known to scientists.They differ not only the shape and size of the body, but also a way of life.Many will be surprised to learn that the shark - it invertebrate fish.They do not have bones!Instead - cartilages which are fairly tough fibrous tissue.
Shark - a collective name.The smallest of all individuals with a pencil, and it weighs about 200 g, and the most awesome can reach a length of 20 meters and weigh up to 20 tons.
best-known species are the great white, reef, hammerhead, tiger, blue shark and polar, and the biggest of them are the giant whale.The diet consists of the last two of plankton and small fishes, which they swallow, filtering the water through many small teeth.The most dangerous and aggressive it considered a rare white shark.At length it can reach 5-6 m, but it happens that some individuals even grow up to 12 meters.
Habitat
entire world ocean inhabited by various species of sharks.As research scientists, even in the deepest hollows inhabited by living organisms, including deep-sea sharks.Without them hard to imagine the sea and the ocean depths.
density resettlement of these predators is extremely uneven.Naturally, the more of them there, where the warm water and plenty of food, namely the coast.
densities are of the oceans
maximum number of shark species and individuals concentrated in the equatorial and equatorial waters.About 80% of living marine predators herein reside in the surface layers to a depth of not more than 200 m. This is due to the fact that these are extremely rich in water the food.
warm temperate seas and oceans of water much less populated these fish - only 16% of the total number of sharks living on the planet.
and cold Arctic seas are very scarce.Therefore, there are very few predators.They swim in these areas only in the warmer months.These cold-tolerant species are polar (Greenland) and giant sharks.
polar shark
It belongs to the genus Somniosidae, or Pryamorotye.Polar shark is the largest representative of the detachment squaliformes.Some specimens of this species reach more than 6 m in length and can weigh 1,000 kg.But scientists-ichthyologists believe that this is not the limit - 8 m in length and weight of 2 tons is possible.Naturally, with such dimensions, it is inactive and is not quite appropriate, to which all are accustomed, namely an energetic, swift and ruthless predator.Polar shark completely non-aggressive, and even if it gets into the network, it behaves calmly, like a log.
It looks mediocre and unattractive: body shape - spindle-shaped, the color - from dark brown to brown with black-purple spots scattered throughout the body.
already one title this huge fish, it is clear that it is found in the cold waters of the Atlantic and Arctic Oceans.Habitat of sharks is quite wide.It can be found off the coast of Iceland, Norway and Greenland, as well as in the northern seas of Russia.In addition, it is found in Hudson Bay and Baffin Bay.In the waters of the Pacific polar shark is common in its northern part, and is also found in Japan and Okhotsk seas.I must say that it feels great in the water with a temperature of +2 to +10 ⁰S.
reef sharks
on coral reefs, lagoons, shallow water, on the border with deep waters often seen reef sharks.They love the clean clear water, so very rarely descend to the bottom.The optimal depth for them - from 8 to 40 m, but sometimes they podlyvayut almost to the shore.
reef shark - a relatively small species.Its length is a little over 2 m. It has a slender body with a broad flat head.Its maximum length, it reaches only to 25 years.Its color is brown or dark gray, sometimes with spots.The belly is always lighter than the back.During the voyage, she makes great undulations and may lie on the bottom and pump water through gills, which are not able to do most of its neighbors.We can say that it leads a sedentary life, because all the time back in one shelter for several years.
Since reef shark is relatively small, it is very often becomes the prey of larger, more aggressive species such as the tiger, or whitetip.
Sharks
Red Sea resort on the Red Sea coast, are not considered to be too dangerous for regular swimmers, divers or diving mask.I must say that initially the sharks do not consider man as their food or prey.They prefer to keep a respectful distance from the big crowds.
Sharks in the Red Sea were carried out always in abundance as the water is warm.In addition, it is well connected with the ocean.For all time there were more than 40 species of these predators.Off the coast of Egypt are not so many, most of the sharks prefer the territorial waters of Sudan.In addition, not all species are dangerous to humans.
All sharks in the Red Sea, in fact, as elsewhere, are divided into the pelagic and those who live in coastal waters akvatorialnyh.The first preference for the open waters, the second - like shallow water, especially reefs.In Egypt, they can often be seen in Sharm el-Sheikh, the reserve of Ras Mohammed, as well as off the coast of Hurghada.
greatest danger of all shark species are the Red Sea, Black Wing, long-winged, zebra, mako and tiger.
people and sharks
now often on the ocean beaches you can see the signs warning that you can not go into the water.The last 10 years, significantly, the cases of voluntary and involuntary shark attacks on humans.
Scientists specializing in their study are confident that this is mainly due to massive uncontrolled catch of fish - the main source of supply of sharks.Therefore, in search of food, they move closer to the coast.In addition, some collisions occur because of carelessness of people coming out into the open sea and to observe basic precautions.Surfers and swimmers only swim in areas where sharks live and hunt that leads to the inevitable clashes.
reasons for the attack
Why scary sharks attack humans?This occurs for several reasons.The first of them - a curiosity.All animals in nature such including shark.And they show their curiosity through the bite test.So, as a man touches his fingers to his subject of interest, and these fish try everything on the tooth.Unfortunately, their touch is much more painful and unpleasant than the touch of a finger.
food competition - this is the second reason for the attack.A large number of individuals in the vicinity, as claimed by an unknown object.Fearing for the interception of prey predator without further doubt attacking and snap off some part of the flesh.It most often occurs during periods of so-called food-fever sharks.
third reason is to protect the territory.As with animals, sharks guarding their land water area from intruders.Especially aggressively defend their territory gray sharks that his whole appearance, or rather, grimaces and poses, show that you are better off, but it did not lash out without warning.
last reason - it is cannibalism.This shark deliberately attack humans, as more than once tasted human flesh tastes.These cases are, of course, a rarity, but their appearance is to determine whether the predator cannibal, is not possible.
Everyone knows that there are super-deep depressions in the seas and oceans, where a person has not yet been able to visit.Therefore, there may lurk a lot of mysteries and interesting and unusual inhabitants of the depths.The cold water of the Arctic Ocean, in our opinion, not very suitable for life, but there is a lot of living things, these include sharks.
