Sharks Sharks are fish with the following characteristics:
The earliest evidence of the ancestors of modern sharks appeared 350 - 400 million years ago, known as the "Age of Fishes". Most modern day shark families had already evolved 100 million years ago when dinosaurs lived on Earth. Unlike other animals, sharks have changed very little since, but it would be a mistake to think of them as primitive animals. Sharks are very streamlined and fast predators with sophisticated jaws, teeth and senses including sight, chemo-senses (e.g. "smell") and have complex electro-sensors, enabling them to differentiate fish from mammals and detect prey in distress (e.g. shaking or swimming irregularly). They are also intelligent, working in groups to herd schools of prey fish, and retreating when deadly competitors or predators are present.
For years sharks have been used for food, oils and vitamins, shark fin soup, fish meal or fertilizer, leather, research, sport fishing and for jewelry. Sharks are sometimes caught and killed by fishers by mistake when fishing for other species. Since sharks reproduce at slow rates if they are not protected, their numbers will continue to decline. If sharks are removed from the web of life, the impacts will be far reaching. By removing the top predator, species at lower levels will boom or explode in numbers and then crash. Sharks keep the population cycles for many other species in check.
Sharks have been billed by Hollywood as the terrors of the sea and people have feared them due to this bad press. Sharks did not evolve to eat people. Humans are simply not on their menu. There is no shark that naturally feeds on man. However, if a swimmer does encounter a shark, in most cases all you have to do is leave the area and they will leave you alone. If it is a large shark leave the area immediately. The risk of shark attack is extremely low. However, all wild predators, regardless or size should be treated with the respect they deserve and not be teased, prodded or provoked.
While sharks are the top predators of the ocean, collectively humans are truly the greatest and most insatiable predator on Earth. Our ability to destroy other organisms and their habitats is unrivaled in the animal kingdom. However, no other animal possesses a sense of the future, understands the importance of other organisms to its well being and possesses the ability for change. It is our knowledge and subsequent actions that will determine the fate of nature's other predators, their prey and the many unique and wonderful habitats they occupy.
Want to learn more about Hawai'i's sharks? Check out the book "Sharks of Hawaii: Their Biology and Cultural Significance" by Leighton Taylor.
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