Sharks

Sharks are often seen as dangerous man eating pretators that should be feared and extingished. Nothing could be further from the truth. Only a few sharks are dangerous to humans. Out of more than 360 species, only four have been involved in a significant number of fatal, unprovoked attacks on humans: the great white, tiger, oceanic whitetip and bull sharks. These sharks, being large, powerful predators, may sometimes attack and kill people, but all of these sharks have been filmed in open water, without the use of a protective cage. Also, most of the recorded attacks were due to the human being mistaken for prey and the shark was just doing what it's survival insticts told it to do. Shark are our friends and should never be extingshed or hunted for sport. They are a vital component of our oceans, they feed on a wide variety of fish, shellfish and mammals. The oceans remain healthy because every organism in it is part of a complex food web. When any component of this web is removed the balance in the system is altered. Sharks are involved in several steps of this web including, feeding on the sick and dying, and feeding on larger animals such as whales, seals and tuna, which have few predators. Since the food web is very complex, it is almost impossible to predict exactly what might occur, but it is safe to say that with loss of an apex predator, there will be noticeable ramifications.

Here are a few myths about sharks that should be corrected:

Sharks are a critical part of marine ecosystems, a source for knowledge to help the human condition and the basis of a valuable fishery. Sharks are the maintenance crew of the sea.

Sharks have poor vision - Erroneous!

Shark's eyes, which are equipped to distinguish colors, employ a lens up to seven times as powerful as a human's, and some shark species can detect a light that is as much as ten times dimmer than the dimmest light the average person can see.

All sharks have to swim constantly - Misconceived!

Some sharks can respire by pumping water over their gills through opening and closing their mouths while at rest on the bottom.

The great white shark is a common, abundant species found off most beaches visited by humans - Guess Again!

Great whites are relatively uncommon large predators that prefer cooler waters. In some parts of their range, great whites are close to being endangered.

Whale sharks, the largest species of sharks, are vicious predators - Not!

Whale sharks, which are the largest fish that ever lived, are plankton feeders like the great whales, thus the name.

Most sharks are harmful to people - Untrue!

Of the more then 350 shark species, about 80% are unable to hurt people or rarely encounter people.

A shark is a shark is a shark - Misconstrued!

There is no "typical" shark. The more than 350 species all differ in habitat, lifestyle and body form.

Sharks are hard to kill - Off Base!

Stress of capture weakens a shark, and so some sharks are easily killed in hook-and-line or net fishing.

Shark meat is poisonous to people - Wrong!

Although there have been some reports of people being poisoned by shark meat, the meat from the majority of sharks is edible and delicious when properly handled and prepared.

Sharks have peanut-sized brains and are incapable of learning - Wrong!

Sharks' relatively large and complex brains are comparable in size to those of supposedly more advanced animals like mammals and birds. Sharks also can be trained.

Most sharks cruise at high speed when they swim - Invalid!

Although some sharks may swim at bursts of over 20 knots (23 miles per hour), most sharks swim very slowly at cruising speeds of less than 5 knots (5.75 miles per hour).

Sharks are not found in freshwater - Incorrect!

A specialized osmoregulatory system enables the bull shark to cope with dramatic changes in salinity from the freshwaters of some rivers to the highly saline waters of the ocean.

Sharks are not discriminating eaters and scavenge the sea - Wrong!

Most sharks prefer to eat certain types of invertebrates, fish and other animals. Some sharks eat mainly fish. Others eat other sharks or marine mammals. Some sharks are even plankton-eaters.

Sharks prefer human blood - False!

Most sharks don't appear to be especially interested in the blood of mammals as opposed to fish blood.

Sharks eat continuously - Preposterous!

Sharks eat periodically depending upon their metabolism and the availability of food. For example, juvenile lemon sharks eat less than 2% of their body weight per day.

Sharks must roll over on their sides to bite - No!

Sharks attack their prey in whichever way is most convenient, and they can protrude their jaws to bite prey items in front of their snouts.

The biggest enemy to sharks is man - Absolutely!

That's why man must now do all he can to preserve them.

Shark Information

Wikipedia Encyclopedia -

A great resource for all sorts of information. The link provide browses to detailed fact on sharks.

White Shark Overview -

ReefQuest Centre for shark research.

The Shark Foundation -

Good resource site that includes information on all types of sharks.

Shark Research Institute -

Execellent up-to-date Shark information site. Check out their "Adopt a Whale Shark" program.

Bite Back -

See how you can help preserve our marine ecosystems.

Marine Science Institute -

Site includes marine conservation involement programs for families located in the San Francsico Bay Area.