Image courtesy of Ramon Llaneza.

From: Ramon Llaneza and Veronica Llaneza
Atlanctic Ocean, North Bahamas , July 15, 2008

What We've Learned About Shark Behavior

We have ended this interesting expedition. We shared very exciting moments and learned a little more about shark behavior and how sharks interact with humans.

Sharks belong to the sea environment and they are on the top of the ecological food chain. They rank among the most perfect and most beautiful creatures ever developed in nature. We expect to meet them at the coral reefs or in the open ocean. Their absence means disappointment for the divers, while their appearance is exciting. When their formidable silhouette glides along the populated coral reef, fish do not panic; they quietly clear the master's path, and keep an eye on him. So do we.

The sharks behave in ways necessary to achieve key biological goals, such as consuming food. The heart of the matter is that sharks do not always behave the same way toward the same stimulus nor do they always wait for an appropriate event to occur. Instead, they alter their behavior in ways that increase the probability of encountering key objects.

In clear water and in daylight, a diver is in no immediate danger if he encounters a shark. Sharks never "attack" a diver below surface. They will circle curiously around you for awhile, go away, and then cautiously return. It is dangerous to show fear of a shark; they can recognize it by instinct, and can profit from it.

The best protection lies in ease of movement in diving, swimming slowly and softly, and avoiding any abrupt changes of position. If a shark should swim toward you, do not try to run away. Face him calmly, he will turn and circle before coming back to you. You will have time enough in which to decide, calmly, whether to remain or to return to the surface. The risk of being involved in a shark accident is 1 in 300 million. Overall, shark attacks are extremely rare. The number of people who are struck dead by falling coconuts is 20 times greater!

It is dangerous to unleash the defensive reactions of a shark by attacking him or even by frightening. When sharks are gathered together in a group, their behavior is unpredictable. Groups of sharks can go into a "frenzy" as they compete for food.

Perhaps most important of all is that the sharks are in serious trouble. More than 100 million of them are killed by people every year through greed, need, selfishness, ignorance, and a depletion of marine ecosystems that sharks are defenseless against. The threatened extinction of many shark species is no longer fiction but grim reality. As sharks have been at the top of the ocean's food chain for 450 million years, their disappearance will inevitably lead to an ecological disaster in the seas and a tragedy for humans.

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Postcards from the Field: Shark Watching

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