Hooked on Sharks in Rookery Bay

Sara Casareto saw a Caribbean reef shark for the first time when she was 12 years old, and she was instantly hooked. Despite being raised by an outdoorsy family and already being scuba certified, the encounter changed her life.

“I have always been drawn to bigger, ‘scarier’ animals,” she says. “That shark sealed it.”

Now a Ph.D. candidate at Florida International University and a Margaret A. Davidson Fellow, Sara is researching shark behavior in an unexpected place: the Rookery Bay Reserve. Since early 2023, she has been trying to answer a critical question: what influences where and how sharks use the Reserve’s waters?

While most people imagine sharks living in the ocean, Sara’s research is conducted somewhere a little different: Rookery Bay’s estuarine environment is likely serving as nursery habitat for multiple shark species. She is exploring whether younger, juvenile sharks spend more time within Reserve boundaries because larger sharks—their natural predators—tend to live further offshore. 

“Knowing how and where predators fit into the estuarine foodweb is important to protect the ecosystem as a whole,” she says. “Think of any food web as a jenga tower; if you take enough pieces out, the whole thing will collapse. Sharks are important predators that keep food webs, including fisheries, balanced and thriving.”

Sara’s work is supported by the NERRS/NOAA Margaret A. Davidson Fellowship, a program that provides funding for research and focuses science on community need. It also connects students to a national network of scientists, mentors, and partners across the National Estuarine Research Reserve System. At the Reserve, she’s passing this mentorship along, supporting Minorities in Shark Sciences (MISS) program interns at the Reserve by helping them gain hands-on experience in the field.

“I’ve had the chance to mentor two MISS interns so far,” she says. “It’s incredible to watch them grow confident in their skills. That’s what keeps me going.”

Now finished with her field work, Sara is already working on her thesis. Once she is done, she plans to start her own lab to study marine predators and create a supportive, inclusive space for the next generation of scientists. When it comes to sharing the excitement and wonder of science, she’s off to a great start: over the two and half years Sara has done work at the Reserve, she’s “hooked” about 70 volunteers, eager to support this work.