Changing Planet

Is Chumming for Sharks Keeping Them Closer to Home?

Everyone has a “happy place,” that special somewhere that comforts and soothes him or her. For Kaia Tombak, a conservation biologist and National Geographic grantee, that happy place is underwater and surrounded by sharks.

“It feels a little bit like being transported into a different world … Sometimes it’s just a big wide blue open beautiful place where you have to go out to find things … and sometimes there’s something right there,” says Tombak, describing the Aliwal Shoal marine protected area off the coast of South Africa.

Aliwal Shoal is home to a bustling tourism industry, and chumming for sharks is one of the main attractions. “About two thousand tourists are doing this every year,” Tombak says. “And the locals have noticed some changes in shark populations over time.” She’s interested in finding out if the extra food is affecting sharks’ migration patterns and, specifically, if larger sharks are migrating less due to the abundance of free handouts.

Learning about the behaviors of sharks helps scientists understand and protect the entire ocean. “Sharks are apex predators, they’re at the top of the food chain. Without sharks, other components of the ecosystem fall apart,” says Tombak.

When Tombak conducts her research she is face-to-face with sharks and she loves it. They’re “a bit curious but they’re shy,” she says. “If you’re looking at them, they get sort of scared off.” In a time of culls and alarming media portrayals of sharks, Tombak hopes her work will help paint a more balanced picture of these misunderstood predators. “They’re something that are really worth saving. Because they’re not these terrifying monsters.”

Hear Tombak talk more about how chumming is affecting sharks in Aliwal Shoal in her National Geographic Weekend radio interview.


Nora Rappaport is a producer and editor on National Geographic's Science and Exploration Media team. She produces content that highlights the awe-inspiring work of National Geographic explorers around the globe. When not working with her colleagues to inspire people to care about the planet, Nora can be found hanging out with any number of dogs.
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