. Sharks-Myth or Menace

by Steve Lissau

July 1980

Surfer Magazine V21 #7..pp33-35

. They say that being attacked by a

shark is about as probable as being

struck by lightning, but when you spot the greyish, torpedo-like form of a big

shark cruising toward you only twenty feet away, the theoretical odds are not very comforting.

. Fortunately, few of us will ever tangle with a share, but when swimming, diving or surfing in the ocean, we will nevertheless think about their foreboding jaws and rows of razor-sharp teeth. For these primitive beasts, which have been on the earth for about three hundred million years, are the only large group of animals left on earth that are capable of eating man - a fate that must be the most horrible death imaginable.

. Yet most shark attacks are single-bite affairs, with the animals using their teeth and abrasive hides to lacerate the victim rather than to tear off a chunk of flesh, suggesting that they were not motivated by hunger. With fewer than one hundred attacks a year around the world, sharks are more a psychological threat than a physical one. But they are a threat, nevertheless, that prevents us from fully enjoying the ocean.

. Tigers of the Sea

Like the sea itself, sharks are shrouded in mystery, and scientists know very little about them. No one knows exactly how many sharks live in different parts of the world, nor do they know much about their breeding and migratory habits. And, as a result of the lack of information about sharks, they have acquired a reputation for being unpredictable.

. Part of the problem is that there are more than three hundred and fifty different species and they all seem to behave differently. Only a handful of these are actually dangerous.

Most of the big offshore sharks that live in the open ocean - such as the Mako, Silky and the voracious Great White (which of course was the villain of "Jaws" and the subject of the film "Blue Water, White Death") -

. rarely stray into coastal waters, and they are mainly a hazard in nautical disasters. However, they do come close to shore occasionally, as- the teeth marks of a Great White shark found in a surfboard after a 1969 attack at Makaha Beach, Hawaii indicate. (The shark had apparently been lured in by the carcass of a dead whale.)

. Sharks that live closer to shore include the Sandbar, Tiger, Hammerhead, Galapagos and Gray Reef. Tiger sharks, which sometimes grow to lengths of fifteen feet or more, currently lead Great Whites in numbers of confirmed attacks. They are the most vicious of the inshore sharks and are known to eat almost anything.

. Such varied items as a woman's handbag, birds, milk cartons, tinfoil, rags, bits of other sharks and human remains have been found inside their stornachs. Tiger sharks can be identified either by their large bodies, blunt noses or the vertical stripes on their bodies when young.

. A Feast of Frenzy

Though the Tiger shark is the only species that feeds so indiscriminately, most people refuse to eat any type of shark meat, probably because of the animal's man-eating reputation and the fear of cannibalism by proxy. This attitude was largely responsible for the elimination of shark from Japanese style fishcake in Hawaii.

. Moreover, sharks were gods to the old Hawaiians, and each family, had their own particular shark god or "aumakua" (which was supposedly born of a shark father and a human mother) that . protected them in the sea. Though it would have been unthinkable to eat one's own aumakua, it apparently was alright to eat someone else's.

. So while the early Hawaiians did eat sharks, they ate only certain species, arid the flesh of "Niuhi," the Great White shark, was forbidden to women.

When properly prepared, the flesh,of most sharks is extremely tasty,, and sharks are regularly eaten in Australia, New Zealand, Canada; Japan and in parts of Europe. In California, shark is, sold as " greyfish.“The only real problem with shark meat is that it's

laden with a metabolic waste called urea that gives off ammonia after the fish dies, thus leaving the meat with a pungent odor. However, the urea can be removed after filleting the meat by soaking it in brine and a little vinegar for about six hours and then freezing it for two or three weeks. Furthermore, fresh shark that is iced immediately won't smell. Shark can be served in any of the ways that swordfish is typically prepared.

. Interesting Observations

How often will you see sharks in the water? Probably never, unless you happen to do a lot of scuba diving in waters known for sharks. Most inshore sharks seem to prefer depths of one hundred fifty feet or so, but as the attack records indicate, they frequently do venture into shallow water. Most shark attacks occur at dusk and dawn, when visibility is limited

and reef fish are separating from schools and are heading back to the security of their holes. (Day fish hole up at night, while night fish hole up during the day.) Since predators like sharks tend to single out stragglers from fish schools, dawn and dusk are the limes when they are most likely to be ^searching for food.

. Moreover, the low light levels give them an advantage since it's easier for them to stalk prey in the darkness and their vision is rather poor anyway.

It should be no surprise, then, that under these conditions of obscured visibility, sharks occasionally bite people thinking they're fish.

Though many attacks seem to be a case of mistaken identity, some are motivated by other factors.

. For example, a shark may attack defensively when molested by a diver or startled by a swimmers sudden entrance to the water. Moreover, when sharks are feeding in a group, they are particularly voracious, and, while in a "feeding frenzy;' they are liable to strike at almost anything.

Some sharks, most notably the Pacific Grey Reef, tend to defend a certain territory which they regard as home,

. and they will attack any person who intrudes in their domain. Typically, they will "threat posture" before attacking, lowering their pectoral (side) fins, hunching their bodies and thrashing their heads wildly from side to side. (So far, threat posturing has been observed only with Grey Reef sharks,) but others, like the Great White apparently attack because they fear nothing and are just plain mean.

. Some Smart Advice

While surfing or swimming at the surface. one has-little chance of seeing a shark and even less of fending him off. Sharks do not necessarily cruise with their dorsal fin out of the water, although they are attracted to objects at the surface when foraging for food. Though a surfboard probably doesn't provide much protection, the chance of an attack is minute compared to that of a freeway collision,

. and with a little common sense it can be reduced even more. Here are some simple guidelines:

Avoid areas that are known for sharks, especially if the water is murky, and leave the water if fish are behaving in an unusual manner. Stay away from spearfishermen since they attract sharks. Swim and surf during daylight

hours and keep splashing (which-sounds like the flutters of a wounded fish to a

. shark) to a minimum. Since human blood probably both attracts and excites sharks, do not go in the water if you have a bleeding wound. (A shark's sense of smell is so keen that it can detect one part of blood in a million parts of water.) Do not swim in areas near channels or deep drop-offs, which provide easy access for sharks.

. Avoid swimming at dusk, dawn or during the night. It you ever happen to spot a shark, keep an eye on him and swim quietly to shore using the breast or side strokes.

Remember, sharks cue in on fleeing prey, so don’t swim too quickly. In unfamiliar areas, ask local residents about shark dangers before venturing out..

. Since their vision is comparatively poor, sharks are most sensitive to bright, reflective colors and vivid contrasts. Thus, a person wearing a dull colored swim suit that matches his skin, would be less likely to be spotted by a shark. Body contrast caused by uneven tanning apparently has also been a factor in several attacks.

Many attacks have been a direct result of spearfishing, since sharks are attracted to both blood and the low frequency sounds produced by the flutters of speared fish. Both stimuli are a dinner bell to sharks, with their keen sense of smell and sensitive lateral line - that can detect the vibrations of a wounded fish from distances as great as three hundred yards.

. (Smell brings them in slower than sound, but from greater. distances.) Currents can carry blood: from speared fish seaward, attracting far away sharks to its source As they excitedly home in, they occasionally bite the fisherman instead of his fish.

Dangerous Game Most

If you do see a shark while snorkeling

or scuba diving, you are in a much better position to deal with hire than a person swimming obviously on the surface. Sharks are curious animals and are always looking for a meal. Consequently, one may start circling you, gradually_. coming closer and closer. When this happens, you should leave the water as quickly and as quietly as

. possible without taking your eyes off the shark. For, as shark expert Rhelt McNair pointed out in a recent article in Skin. Diver magazine, sharks circling a diver seem to be very aware of his eyes, and they will keep their distance as long as they know that they are being watched. However, the moment one turns away, they will move in. When a shark starts making close passes, many divers recommend taking evasive action toward the animal in order to

. drive him off. Providing that the shark is not a very big one, you may be able to scare him away by simply moving toward him while yelling and blowing bubbles. If this doesn't work, you might try to hit him with a blunt object such as the butt of a speargun (sharks often react aggressively when poked with a sharp object like a spear or knife) in his eyes, gills or snout, which are the most sensitive parts of his body.

Though my friend the late Jose Angel, who used to hunt sharks underwater for sport with an explosive powerhead, once told me that sharks behave like scared dogs when they know they are being stalked, one should also remember that aggressive action toward an otherwise docile shark may cause it to attack in self-defense.

.A defensive approach is recommended with excited sharks such as a threat-posturing Grey Reef. By backing yourself up against a wall or large rock (if one is available), which will prevent the shark from maneuvering around you, you will force him to come at you from a head-on direction, which he may not want to do. In this situation, the animal will sometimes withdraw and sometimes attack.

If he chooses the latter option, you will at least be in a good position to deliver a blow to one of the sensitive areas of his body before he hits you, and the surprise contact may drive him off. But if it doesn't, the odds are that you will be bitten only once. Afterwards, you should immediately try to reduce the bleeding using both direct pressure and a tourniquet (if the wound is on an extremity).

. Loss of blood is the main cause of death from shark attack.

So sharks, like ancient dragons from

the deep, continue to be the symbol of

fear in the ocean, and because of this many ideas about sharks are myths. Two erroneous beliefs are that they must always keep moving in order to breathe, and that porpoises are capable of killing them.

. To the contrary, many species of sharks (notably the Reef Whitetip, which sleeps in caves during the day) can remain motionless for long periods, since they have muscles to pump water through their gills: and porpoises will curly occasionally fight sharks as a last resort to protect themselves or their ,young. Moreover, they don't always win, and scientists have found it

impossible to get a porpoise to attack a shark under controlled laboratory conditions.. But sharks themselves are not myths: they are more like characters in a recurring bad dream, lurking in the shadows beneath the indigo surface of the sea.

. Though the odds against attack are as great as being struck by-lightning, you don't need to live through the experience to respect the danger and take precautions to reduce the risk.

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