Sharks Help Keep Ocean Healthy Wealthy and Wise

Nature’s Corner is featuring a four-part series in June to introduce you to sharks. We’ll cover a bit of their anatomy and behaviors, some species you’ll see here in the Florida Keys and what dangers sharks might pose. For some people, their perception of sharks make them an animal of people’s nightmares.

A catch of sharks on a barge in Key West harbor for the shark leather fishing industry in the 1930s.

However, once you gain more knowledge about them, some of that fear may disappear. Sharks play a vital role in keeping our reefs and ocean environment healthy by removing sick and injured fish from the ecosystem. This removal greatly benefits our way of life, providing us with both beautiful reefs for us to enjoy and healthy fisheries to obtain food for our tables. Even if sharks are a bit scary, they still do a great deal to help us. Because of how important they are to us, it is necessary to understand what makes a shark a shark. With a backbone and gills, sharks are classified as a type of fish. A shark’s skeleton is made of cartilage, the same as your ears and the tip of your nose.

There are over 400 species of sharks, ranging in size from 6 inches to 40 feet. Put differently, sharks can range from the size of a dollar bill to the size of a school bus. Sharks are able to see and smell very well in the water, but they also have other senses to help them find food and sense the world around them. Using specialized organs called the ampullae of Lorenzini, located on their heads, sharks can sense electromagnetic pulses. In addition to detecting the electric field, sharks also have a line of specialized sensory cells, called a lateral line, to detect vibrations in the water.

Have you ever found a shark tooth washed up on the beach? That’s because sharks lose teeth constantly; some sharks can lose tens of thousands of teeth in their lifetime. A shark’s teeth are specifically designed for the type of food they typically eat. For example, a bull shark usually eats fish, so their top teeth are skinny and pointy while their bottom teeth are large and serrated. Bull sharks use their teeth like a fork and knife in order to tear their food. With sharp teeth, sharks can be a little scary for us land dwellers. However, a lot of our fear comes from not knowing exactly how these predators behave.

Luckily for us, humans are not on a shark’s menu of prey items. So next time you see a shark when you’re enjoying the reef, take a deep breath and simply give the shark some space. If you’re feeling nervous, calmly make your way back to your vessel or to shore so you don’t draw attention to yourself. Want to have a chance of seeing one of these interesting animals in their natural habitat? Take a glass bottom boat, snorkel or dive tour out to the reef through one of our local state parks.

Visit to plan your next adventure. Lindsey Crews is a park ranger at John Pennekamp Coral Reef State Park.