[ Free report ] Eco systems of coral reefs in Egyptby Diana Gamazova | 21-10-2020 01:04 |
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 Hello to everyone! And I am back from our 17 days vacation on the shore of the Red sea. How all you know the biodiversity of coral reefs in Egypt is one of the mos beautiful and richest on our Earth, if you are not familiar with it, I strongly recommend you to watch documentaries about seas of David Attenborough, because only then you will fully understand what is the ecosystem of the great coral reefs. And this time, we saw a turtles, eagle rays and a WHALE SHARK!! Seeing the 20 meters long whale shark in the wild was a true miracle, so my report today is about those wonderful and large creatures - whale sharks. The whale shark is the largest fish living on the planet. In many countries, special excursions are arranged for tourists, allowing them to see her in her native element. Scuba diving side by side with this harmless giantess leaves a lasting impression for a lifetime.The whale shark lives in the Atlantic, Pacific and Indian oceans. It is most often found near the Seychelles, Madagascar and off the coast of South Africa; it is also often seen in the Kuroshio Ocean Current, the Gulf of Mexico and the Caribbean Sea. Inhabiting warm-water regions of the World Ocean, it most willingly keeps in places where the temperature fluctuates around 21-25 ¡Æ C all year round. Every year, the whale shark makes seasonal migrations to river estuaries and coral reefs.The breeding method of the whale shark has long been the subject of lively scientific controversy, although most ichthyologists considered it an ovoviviparous fish. Finally, in 1995, a female 11 m long was caught, in whose body there were about 300 eggs with embryos at different stages of development ranging in size from 42 to 63 cm. In all likelihood, the female is ready for mating once every three years. If during this period she meets a suitable male, partners can mate. Since sharks need a calm environment for this important business, mating usually takes place at night near the very bottom. After internal fertilization, the eggs remain in the mother's body. The term of gestation of developing embryos is unknown to scientists. Presumably, in one brood, about two dozen well-developed and ready for independent life cubs about 50 cm long are born. The juveniles grow rapidly, adding 20-30 cm in length annually, but with age, the growth rate slows down. The mortality rate among juvenile sharks is 90%. The whale shark reaches sexual maturity at the age of about 21 years with a body length of 7.7 m.An adult whale shark has no enemies in nature: a strong skin on the back 12-15 cm thick reliably protects it from the teeth of any predator. Young whale sharks are hunted by marlins, predatory sharks and killer whales, but the most serious danger for this species comes from humans. With high demand for whale shark meat and fins in the 1980s. its annual catch has increased from a few to several hundred, which has led to a sharp decline in the population. Another reason for the decline in the population of this fish is late puberty and low fertility. Currently, the whale shark is recognized as an endangered species, and hunting for it is strictly prohibited in the waters of the Philippines, Honduras, Australia, the Maldives and South Africa. Conservation measures are also taken in the Gulf of Mexico and off the coast of California,The whale shark inhabits the surface water, swimming with unhurried majesty. Sometimes whale sharks get lost in small groups, but much more often they wander completely alone (more or less large schools of these fish are observed only off the northwestern coast of India). The food of the whale shark consists of planktonic organisms and small fish such as young mackerels and tuna. During feeding, the shark sucks water with edible trifles contained in it into the open mouth and filters it through the gill openings, through a fine sieve of spongy tissue, which is supported by cartilages that connect the gill arches. Having found a place, the shark takes a vertical position with its head up and, moving its mouth at the very surface, sucks in water along with plankton, squid and fish. Usually, a feeding shark combes the chosen area in slow circles, but can dive to a depth of 700 m.I hope it was interesting, I can talk about those giants forever, that how amazing was to meet her/him in the sea. So in the comments, I am curious does anyone had an experience such shocking as mine? Maybe you have met some interesting animal in the wild, so please shear your story with us!!! |
