Sharks: Keeping our oceans in balance

Sharks are absolutely amazing - we all know this! They are certainly some of the greatest superheroes in the ocean. With incredible swimming, hunting and camouflage capabilities, not to mention amazing vision and sensory abilities, sharks are everything extraordinary, rolled into one animal. But did you know that sharks have the little-known, but much-needed superpower of keeping ecosystems in balance?

The food web is a delicate system that needs to be kept in balance for the ecosystem to remain healthy and thrive. Being highly effective predators, sharks feed on animals lower in the food web and keep the populations of these species in check. Simply put, sharks prevent the numbers of smaller predators and grazers from becoming too high, which in turn allows smaller animals to thrive. If sharks weren't there to prey on the middle-tiers "mesopredators", their prey would be over consumer, and there would be lower abundance of food for these mesopredators - meaning that through food scarcity, they would be in a worse position than if sharks were around to prey on them!

Not only do sharks control the population numbers of their prey through predation, but simply their presence in an area can also cause their prey to move to other areas, preserving smaller species and other essential ecosystem elements in a particular area. A great example of this was highlighted in a study that looked at what happens when sharks are removed from coral reefs. The removal of the sharks led to an increase in smaller predators. With smaller predators in the area, the number of herbivores, that would normally graze on the algae that grow on the coral, decreased. Fewer algae eaters meant that the algae were allowed to overgrow and smother the coral reef. Not only was the ecosystem completely changed by the algae growth, but the biodiversity in that area was also irreparably changed.

Did you know that sharks, and other large animals in the ocean, can help fight climate change by storing carbon in their bodies? A whale shark, for instance, can weigh 19 tonnes. That is 19 tonnes of carbon! By removing the largest animals of marine species, humans have reduced the amount of carbon that can be stored in those animal populations. It has also altered the ocean’s ability to sequester carbon.

We hope that next time when you visit the Aquarium and marvel at the sharks in the Save Our Seas Foundation Shark Exhibit, you will keep in mind that these majestic animals are not only beautiful and sleek but are also superheroes that play a vital role in keeping the marine ecosystem healthy, by this being.

Bonus – when visiting the Save Our Seas Foundation Shark Exhibit, be sure to also stop in at Shark Alley, which runs along the perimeter of the live exhibit. Shark Alley has fascinating facts on shark behaviour, ecology, and biology. Here you will learn all about what makes sharks’ physical appearance so unique and you can dive in deep into why we need to protect shark populations at all cost.