Biscayne Bay is Miami’s busy playground, but new data reveals it’s also a critical nursery for threatened sharks and rays. Now, with more development on the horizon, what’s at stake? 7’s Heather Walker investigates.
Biscayne Bay is filled with boaters, swimmers, and it’s a backdrop for Miami’s skyline, which is home to millions of people. But below the surface, these waters are serving a very different purpose. One that could be critical to the survival of threatened sharks and rays.
Catherine Macdonald, Director of the Shark Research at University of Miami’s Rosenstiel School: “For more than 10 years, my team’s been collecting data on how sharks use the habitats in Biscayne Bay. And what we found is that for 13 species of shark and ray, Biscayne Bay is critical to some aspect of their lives.”
The work done by Catherine Macdonald and her team at the University of Miami’s Rosenstiel School put Biscayne Bay on the map. For the first time globally designating it as an “important shark and ray area,” also known as ISRA.
Catherine Macdonald: “So often when I talk to folks who live here, they’re surprised to hear that we have such an ecologically important space right in our backyard.”
South Florida scientists found the bay’s shallow waters, seagrass meadows and old reef systems provide the perfect nursery for sharks and rays, including eight species that are considered threatened.
Catherine Macdonald: “Typically, a nursery either is a place where a shark is less likely to be eaten by a big predator or is more able to find food and grow more rapidly. So Biscayne Bay is probably one or both of those for many of these species.”
Everything from big sharks like tigers, bulls, great hammerheads, down to very small sharks like the little bonnethead shark.
Heather Walker: “So some people aren’t fans of sharks. Why is it important that we protect the sharks?”
Catherine Macdonald: “So sharks are an important part of healthy marine ecosystems.”
Ecosystems that are already under a lot of pressure from global warming and coastal development. Scientists hope designating Biscayne Bay as essential to survival will be a factor when the city makes future development decisions.
Catherine Macdonald: “I think that it’s really easy to see things only in terms of dollars and cents in the context of a big city like Miami, and I would just say that the bay and the organisms that live there are also our neighbors and that we’re going to have a happier, healthier city if we care for our neighbors.”
Scientists hope bringing this discovery to the surface will help protect the animals living below.
Heather Walker 7News.
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