Sharks in the Black Sea: true or myth?

Some people, especially after sensational reports about attacks of sharks in the resorts of Egypt, asked the question: are they safe for bathers and divers of the Black Sea? Do sharks generally live in the Black Sea, and can you meet them on the coasts of the Caucasus and the Crimea?

In order to comprehensively answer this question and calm all anxieties, it is simply necessary to make an excursus, even brief, into the history of the origin of the water area, which is now commonly called the Black Sea. 10 million years ago there was a huge pond that scientists called the Sarmatian Sea. Gradually the Sarmatian Sea with the growth of the mountains was divided into a number of large seas, lakes, cut off from the waters of the World Ocean: Aral, Caspian and Black. This last, due to the huge number of rivers flowing into it, began to desalinate. Over time, the entire fauna inhabiting the ancient Black Sea-Lake became freshwater. But 8 million years ago there was a huge earthquake that created the Sea of Marmara and the straits of the Bosporus and the Dardanelles and proved to be fatal for the then inhabitants of the Black Sea. Salt water masses poured from the Mediterranean into the Black Sea. The changes were so rapid that the freshwater marine inhabitants of the Black Sea did not have time to adapt to them. A huge number of dead bodies descended to the bottom, and the process of their decomposition made the Black Sea exceptional, unlike other seas: a hydrogen sulfide layer appeared, located below 150 m from the surface of the water.

This layer of hydrogen sulphide makes the vast expanses of the Black Sea unusable. Below 150 m there can exist only sulfuric anaerobic bacteria, which only increase the percentage of hydrogen sulfide by their vital activity. This circumstance - the narrow layer in which the fish lives, very hardens the life of such large and dangerous predators as sharks in the Black Sea. But hydrogen sulphide is not the only factor that blocks the way sharks. A large number of rivers and the narrowness of the Bosporus strait are visibly desalinated by the waters of this sea. Suffice it to say that the salinity of the Black Sea is half that of the Mediterranean Sea. In addition, in winter the surface of its water can be cooled to + 9 C, which is very uncomfortable for those inhabiting the cool, but still not cold waters of the Atlantic. Sharks and the meager fodder base of the Black Sea are unsuitable for sharks: large predators prefer large and schooling prey that lives in the depths of the water, whereas the Black Sea is rich in small fishes: anchovy, sprat, sardines that live in the surface layers of water.

If we assume that some shark and swim in the summer from the Mediterranean to the Black Sea, it is unlikely that it will get far from the Bosphorus because of the unsuitability of water and the scarcity of food. But still there are sharks in the Black Sea, and even two kinds. But do not be in a hurry to get scared! This shark-katran, also called a dog shark because of the similarity of the muzzle, and cat's shark. These two species feed, like the Black Sea dolphins, with small fishes, moving in small flocks. They do not eat people, although their mouths, again, like dolphins, are full of teeth. But people willingly eat these small sharks: steaks from katrana are considered in the Crimea a great treat, and balyk from katrana is valued in the same way as balyk from sturgeon, since this fish has almost no bones, and its meat has excellent taste.

However, it is not necessary to dismiss the danger of a shark in the Black Sea: the katran on the fin has a sharp spine, which causes pain and can provoke inflammation of the wound. Although for cats and cat shark it is not common, sometimes they swim in shallow water, and you can just step on them. In this case, the fish can start with a fright and teeth. But such a case was recorded only once for all the years of observations (in the 1970s on the beach of Evpatoria). The most dangerous animals for humans in the Black Sea are not sharks, but stingray rays. Their backs are equipped not with simple thorns, but poisonous. A portion of the injected poison is not fatal to a person, but can seriously spoil his vacation, as the limb from the bite swells. There are cases of deaths (though not in the Black Sea) from the impact of a spike in vital organs. But, in general, the Black Sea is considered the safest in comparison with others.