Shark Statistics Vs. Myths

Preconceived Ideas

Before going into detail into all the scientific studies or the indisputable evidence which have permitted a much better understanding of the world of "Squaliformes", it would seem of interest to put right certain falsehoods, approximations, even scientific blunders, concerning these fascinating animals.

• Sharks attack in order to feed.  the image of the insatiable shark that swallows everything it encounters in order to assuage a hunger that is never satisfied is one of the most false.  According to Balbridge and his reference work on 1500 cases of attacks on man, 50-75% of these attacks have nothing to do with nutrition.  This does not resolve much concerning the danger linked with sharks, but we shall see that it is a determinant parameter for explaining, on the one hand, certain single bites, which are not repeated and do not involve the removal of flesh, and, on the other, the effectiveness of certain preventive measures.

• Hunger does not exist in sharks.  In apparent contradiction with the preceding proposition, this is none the less untrue.  The shark is capable of very long periods of fasting, and it seems that it may have a periodicity in its eating habits.  During these "eating phases" it is evident that we can talk of "hunger", and attacks will then be different in their determination and development.

• The shark is a primitive animal.  Even if it is true that the order of fishes is the most rudimentary in the hierarchy of animal evolution, the shark is much more sophisticated  than we believed it to be only 20 years ago.  Besides sense organs that are particularly outstanding and unique in the animal world, the size of the brain is closer to that of birds (proportionately speaking) or of certain primitive mammals than to that of any other fish.  We shall see for instance the exceedingly sensitive character of the olfactory organs in the shark, reflected at brain level by highly developed olfactory lobes.  Several other physiological characteristics prohibit any talk of a primitive animal and, moreover, such a creature would not have come through 350 million years without appreciable evolution.
• The shark has very poor eyesight.  Even Captain Cousteau subscribed to this unfounded belief.  Not only can it see contrasts well, but it has good night vision thanks to a histological structure peculiar to nocturnal animals (the tapetum lucidum).  It can even see colors.
• The shark's pupil is at all times widely dilated, adding to its terrifying appearance.  This is false: the iris has an ovular shape and the pupil can be dilated and constricted very rapidly.  Some species possess a third eyelid (nictitating membrane) which closes at the moment of attack (as in the case of all Carcharhiniformes, including Tier, Bull and Oceanic White-tip Sharks).
• The shark attacks to defend its territory.  This has never been demonstrated for any species, even for the reef sharks which are fairly sedentary.  This concept of territory is standard for terrestrial animals which set the boundaries of it by their droppings, but the extension of the principle to fish seems without foundation.  Perhaps we could speak instead of defense of a vital space immediately around the shark when it feels threatened.
• The shark rolls on to its side to attack.  The shark's anatomy and scientific observation refute this popular belief, which must date back to ancient times, as Pliny mentioned it.  The shark approaches its prey from an angle, plants its pointed lower teeth into the flesh, then brings its upper jaw forward to plant its cutting teeth in.
• The shark does not eat dead bodies.  Ten or so examples are cited on this website which refute this belief, some of them supported by photographs.  In 1950, Mr. Warne, an Australian fisherman, found the barely digested right hand of a human being in the stomach of a 1.5 meter Tiger Shark.  the police identified it as belonging to Peter Szot, whose body - minus the right hand - had been recovered on a beach eight days earlier, with a bullet in the head.  Mr. Szot had not committed suicide after having lost his hand, but before.

Preconceived ideas are not very important when not put down in writing.  When, on the other hand, they claim to be guiding rules for the attention of the trusting reader, they can lead to a lethal ignorance.  This is how we came to read the following absurdities in old versions of the survival manuals of the US Army:

"The shark is a cowardly fish which moves about slowly, easily frightened by surprises in the water, noise, movement and unusual shapes.  This last point alone would be enough for a shark not to attack a man."  This cartoon-character description was followed by a paragraph on the best way of combating this "wretched" fish: "First of all strike it on its soft and vulnerable snout or in the eyes, or stab it in the gills."  The authors then boldly advised "swim outside the line of charge, catch hold of a pectoral fin as it passes, and ride with it for as long as you can hold your breath."  The most savory piece of sitting-room advice imaginable, but this was only a start.  "If you can manage to cling to it, the shark may lose some of its vice and regain its natural cowardice.  If you have a knife, open up its stomach.  On opening the stomach, you cause water to enter - that would kill it almost instantaneously."  Phenomenally stupid words, in which the US Army pilots and marines were supposed to immerse themselves before their missions.

One reader of the manual, who managed to survive a shark attack in spite of the book's advice, related how he fired his Colt 45 at the "soft and vulnerable snout".  "It then turned around to charge, and so I started to bang it on the top of the skull with the Colt.  Its head was as hard as metal at this spot and I later discovered that I had partially flattened the small steel eye on the grip, at the point where the strap is attached."

The present-day "survival book" of the American Army is reduced to the basics, as if the authorities had opted for a helicopter behind every GI, rather than for a good manual in every battledress.