What if sharks go extinct

As apex predators, sharks play a vital role in the ocean ecosystems. Every year million sharks are killed by humans and that number is only increasing. As human activity continues to put sharks in critical danger, it makes scientists wonder: What would happen if every shark on the Earth disappeared today? The answer is very scary. Coral reefs have an delicate ecosystem balance. Algae grows on coral, which is eaten by herbivorous fish.

Herbivorous fish are then eaten by larger predatory fish which are eaten by sharks. When sharks are in decline, less of the large predatory fish are eaten, which means that more of the herbivorous fish are eaten, and in turn, less of the algae is eaten. The algae competes directly with the coral, and too much algae kills coral reefs. After studying miles of coral reef, the information on sharks the scientists found showed that declining shark populations as result of overfishing have had disastrous impact on coral reefs.

So if all sharks disappeared, coral reefs would also vanish. Another problem as a result of this imbalanced food chain noted in coral reefs, is that the excess growth of algae blooms would suffocate the ocean. Algae blooms suck the oxygen out of the water creating low oxygen levels. Without oxygen, marine life will suffocate to death.

This is a phenomenon that has been observed worldwide in both oceans and freshwater. Also, some algae blooms can also produce toxins that get into the water. These toxins are incredibly harmful to marine life and can lead to mass die-offs. Algae can also be very toxic for people. Download it for iOS or Android — and sign up for alerts. Local In-depth news coverage of the Greater Boston Area. New Hampshire 11 mins ago. Listen to our free podcast , " Shark Tales ," which explores the world of sharks in New England with our partners at the Atlantic White Shark Conservancy.

It's on Apple Podcasts , Spotify or wherever you get your podcasts. Be on the lookout for tons more shark-related content from Discovery, PBS, and others this week. Be respectful, keep it civil and stay on topic. We delete comments that violate our policy , which we encourage you to read.

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