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It Takes 5 Minutes to Keep Sharks Swimming

By Dr. Steve Kessel, Director of Marine Research at Shedd Aquarium Did you know that over 400 species of sharks call our oceans home? These predators originated around 450 million years ago, persisting through five mass extinction events since that time. Perhaps not as old as dirt, but sharks are older than trees by about...

A Caribbean reef shark swims in the waters of the Bahamas with several horse-eye jacks and yellowtail snapper surrounding it. ©Shedd Aquarium/Brenna Hernandez

By Dr. Steve Kessel, Director of Marine Research at Shedd Aquarium

Did you know that over 400 species of sharks call our oceans home? These predators originated around 450 million years ago, persisting through five mass extinction events since that time. Perhaps not as old as dirt, but sharks are older than trees by about 100 million years. For all those millennia, sharks have been vital to maintaining healthy and thriving ocean ecosystems.

Though sharks are some of the most powerful animals in the ocean, even they are not immune to problems like targeted fishing, habitat destruction and pollution. Many shark species are experiencing alarming declines across the globe, from which they struggle to recover because their life history is not suited to large scale exploitation.  They invest a lot of energy in producing a smaller number of large young – for better chance of survival – and it takes many years for the young to reach mature, reproductive age. So, when we deplete populations it becomes increasingly difficult for recovery.  Now, around one-quarter of all chondrichthyan fish species (sharks, skates and rays) are threatened with extinction.  As humans are most accountable for these population declines, we are also most responsible for protecting sharks into the future.

One tool to protect sharks is creating shark sanctuaries. Coastal and island governments can designate an area that would prohibit the commercial fishing of all sharks, and the retention of sharks caught as bycatch.  Additionally, the possession, trade and sale of sharks and shark products within a country’s full exclusive economic zone can be prohibited. There are currently 17 shark sanctuaries in the world, including The Bahamas.

The effectiveness of shark sanctuaries is illuminated by The Bahamas, which has one of, if not the most, viable and intact population and diversity of shark species in the western Atlantic. The Bahamian government designated its national waters as a shark sanctuary in 2011, creating an approximate 630,000 square-kilometer safe haven for sharks. Not only an important step to protecting these animals, this shark sanctuary also provides ecological, cultural and economic benefits for the area. For example, a 2017 study discovered that shark- and ray-related tourism contributed $114 million to the Bahamian economy in a single year, with 43 percent of all dive tourists coming primarily to see sharks.

The Bahamas Shark Sanctuary

This progressive approach to shark conservation can serve as an example for additional sign-on from other nations in the Caribbean, but the success needs to be assessed and monitored to ensure its long-term implementation. That’s where Shedd comes in.

Shedd’s research team provides crucial data that helps to protect sharks and their ecosystems through: 1) assessing the relative abundance of biodiversity of sharks and rays in the Caribbean region, 2) identifying the near and far benefits of The Bahamas Shark Sanctuary, and 3) investigating the relationship between ecosystem carrying capacity and relative shark abundance.

Off the back of Shedd Aquarium’s research vessel, the R/V Coral Reef II, I collect tissue samples from a Caribbean reef shark to contribute to Shedd’s shark research. ©Shedd Aquarium/Brenna Hernandez

This spring, we tagged and released a variety of shark species inside and outside the Exuma Cays Land and Sea Park, established in 1958 as the first Marine Protected Area (MPA) in the wider Caribbean. The collected data will add to our long-term research study of sharks in The Bahamas, which will be used both to promote sharks as critical indicator species for assessing the condition of marine ecosystems.

To celebrate Shark Week this year, we encourage everyone to speak up for sharks and spread the word about why we need to keep sharks swimming for healthy oceans. As upper-food-web predators, sharks are crucial to maintaining the biological diversity and therefore the ecological balance and health of their environments. We want to create a more accessible way to bring the public face to fin with them in the wild to inspire and spark personal action.

Through Shedd’s Keep Sharks Swimming conservation campaign, people can support shark sanctuaries in The Bahamas by signing a letter of support to The Bahamas’ Minister of Agriculture and Marine Resources, donating to Shedd’s shark conservation research, or shopping for custom shark designs on Threadless where part of the proceeds go to Shedd’s research programs. By visiting the website,, you can also virtually swim alongside sharks in The Bahamas and in Shedd’s Wild Reef exhibit and become immersed in their underwater world with exclusive 360 videos.

Visit www.sheddaquarium.or/keepsharksswimming to learn more about the importance of sharks and how you can protect them.

Caribbean reef sharks swim in Bimini, Bahamas. These vibrant blue waters are part of the Bahamas shark sanctuary, which prevents harvesting of shark species, commercially or recreationally, anywhere within the 630,000 square-kilometer safe haven of Bahamian waters. ©Shedd Aquarium/Brenna Hernandez

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Meet the Author

Shedd Aquarium
The John G. Shedd Aquarium in Chicago sparks compassion, curiosity and conservation for the aquatic animal world. Home to 32,000 aquatic animals representing 1,500 species of fishes, reptiles, amphibians, invertebrates, birds and mammals from waters around the globe, Shedd is a recognized leader in animal care, conservation education and research. An accredited member of the Association of Zoos & Aquariums (AZA) and the first U.S. aquarium to be awarded the Humane Conservation™ certification mark for the care and welfare of its animals by American Humane, the organization is an affiliate of the Smithsonian Institute, and is supported by the people of Chicago, the State of Illinois and the Chicago Park District.