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Shortfin mako shark (Isurus oxyrinchus), splendid raider already described in 1952 by E. Hemingway in a touching conflict between man and animal, currently result to be one of the fastest and powerful known sharks.. This animal succeeds in ploughing the seas to the unbelievable speed of 70 km/h and to escape from the water with leaps that lift him completely up to 5 meters!
The jumps are often observed
when the shark is captured to the hook, during the commercial of
sporting fishing and the shark tries real stunts to recover the liberty.
Despite these dangerous
enemies, natural and not, this shark continuous to dart in tropical and
moderate waters, with superior temperature to the 16°C.
The shorfin mako shark, as already mentioned, has great power, that brings him to attackg great and fast preys as tunas, sword fishes, dolphins and other sharks. The form of the teeth is triangular, with the point oblique slightly perfect to snap and to dismember great portions of meat. The dimensions complete this great aggressive potential, with a middle length from 200 to 250 cm, up to 400 cm and a weight superior to 500 kg!
This shark potentially reenters among the 5 more dangerous sharks for the man, together with the white shark (Carcharodon carcharias), to the tiger shark (Geleocerdo cuvier), to the zambesi shark (Carcharhinus leucas) and to the oceanic white tip shark (Carcharhinus longimanus), being responsible of some not provoked attachs to the man.
We always have to remember
however that these attacks reenter in the annual statistics, that see to
happen in all the seas of the world around 60 shark attacks to the man,
of which 6-8 deadly. Man, with a redoubt muscular mass and a least
quantity of bodily fat, is not a natural prey of the shark and in fact
in almost all the attacks, after one or two "test" bites, the great
raider definitely gets further without devouring the bodies.
Unfortunately however also an only bite of great samples can be enough
to cause serious lesions or the death. (recommended
reading; shark attacks)
The shortfin mako shark has a
particularly rigid and hydrodynamic body, elements that help to reach
elevated speeds. Also contributes to this the great caudal fin, with
both the lobes developed. The face is pointed and the pectoral fins
small. The eyes are great and black and the teeth often in evidence.
The shortfin mako shark, as the
white shark (Carcharodon carcharias) has developed a mechanism of
maintenance of the heat that allows him to have a bodily temperature of
4 - 5 °C superior to that of the water that surrounds him and up to 10C°
as it regards the most inside musculature. This mechanism, the
so-called "rete mirabilis", give a greater reactivity of the
musculature, great benefit to the shark as regards the times of
digestion of the preys, that result faster, immediately making available
for the animal great quantity of energy.
SHORTFIN MAKO SHARK
Note 1: Isurus oxyrinchus, described the this article it is very similar to Isurus paucus, that has the pectoral fins longer and least pointed nose.
Bibliography: - "Sharks & Rays,
Elasmobranch Guide Of The World". Ralf M. Hennemann,
Marco Angelozzi - www.prionace.it
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