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The sea it is not our home, but we behave like masters and we are shocked if by chance we meet his real inhabitants. Of all, sharks scare us the most. It will be for the cinematographic iconography, for the fame of fearsome predators or for their slightly primordial aspect. A fearafter all, unfounded. Let’s see why.
Sharks in the Mediterranean
In the Mediterranean there are over 80 species of cartilaginous fish, among sharks, rays and chimeras. As for sharks, in our sea there are, for example, lamnids like it White shark (Carcharodon carcharias) and lo mako shark (Isurus oxyrinchus), carcarinidae including the blue shark (Prionace glauca) and it bronze shark (Carcharhinus brachyurus), odontaspididi like lo bull shark (Carcharias taurus), alopidae including lo thresher shark (Alopias vulpinus), sphyrnidia such as lo great hammerhead shark (Sphyrna mokarran), and cetorinide basking shark (Cetorhinus maximus).
Encounters with sharks are rare
“The dating with these animals they are in general rarein the Mediterranean as in the rest of the world “explains a Wired Sara Bonanomiresearcher at the Institute for Biological Resources and Marine Biotechnologies (Irbim) of the National Research Council (Cnr). “In the summer there is a peak of sightings both offshore and near the coasts because we are the ones who frequent the marine environment more”. Bumping into a shark, although it is not a frequent occurrence, is therefore always possible. With which species it depends on area of the sea in which we find ourselves. Although the population is decreasing, the blue shark it is still quite common along i central-northern Adriatic coastswhile recently there have been sightings of mako shark in the Tyrrhenian Sea is in the Ligurian Sea. The bull shark and the hammerhead shark, on the other hand, are by no means common and their reports often turn out to be unfounded. “Even it White shark it is present in the Mediterranean, but today it really is very rare“, Bonanomi points out. “It is found mainly in the waters near the coasts of north Africaand it is no longer a habitue of Italian waters. In general, it follows the movements of its natural prey, that is tuna and marine mammals: the decrease of these species has also led to the contraction of its population, accentuated in the past centuries by jokes of targeted fishing And by-catches in different fishing gear “.
Shark danger?
Whether sightings and encounters with sharks are to be considered rarethe attacks to the human being they are more and more (we talked about it here). “Sharks are shy animals, which do not seek human beings. We are not even on the menu of the major predators and any attacks are to be considered, most of the time, as reactions toinvasion of their habitat. Some, then, are in no way dangerous, like him basking shark that despite the appearance and size (as an adult it can reach 9 meters in length, ed.) can be misleading, it has rows of teeth of a few millimeters “continues Bonanomi. “If you happen to come across a shark, the recommendation is to keep it as much as possible calm and of step away from the animal. Sharks are indeed gifted with very developed senses which allow them to capture not only blood and urine, but also the magnetic field of what is in the water in their vicinity. Better to avoid getting agitation signals that could make them nervous “.
Sharks in danger
Although the presence of sharks in our waters may worry someone, it is necessary to emphasize that these animals statistically I’m not a danger for the human being. The opposite is not true: human activities are causing populations to shrink of many species, as evidenced by the data collected by the World Union for the Conservation of Nature (Iucn), in which red lists (also available for Italy here) are listed endangered species. “The main causes are the accidental fishing is that illegal. Often the capture takes place when the animal has not yet reached sexual maturity, which in sharks occurs very late given their very slow growth rate “adds the CNR researcher. “L’rising sea temperatures and it shift of climatic bandsinstead, they have a much less impact on sharks than on other species. Sharks are among the most ancient animals that exist and their biology allows them to live very long, in some species even hundreds of years. This longevity, in some ways, makes them resistant to changes in the environment “.
Although some shark species are protected under various conventions, directives, even international regulations, according to Bonanomi little has been done for conservation of populations in the Mediterranean. Just to give an example, shark mako And emery (Lamna nasus) still come caught and sold illegally, passed off as swordfish. For raise awareness the population, improve the storage of some species and to promote conservation practices in the context of professional fishing, the European Union funded the international project ELifein which our Cnr also participates. “Everyone, in their own small way, can contribute to protecting sharks”Sara Bonanomi concludes. “We should prefer the consumption of zero kilometer fish and not to consume exotic dishes made from shark meat, and also avoid cosmetic products that contain squalene derived from shark liver“.
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