Tiger sharks helped discover the world’s largest seagrass prairie
Scientists equipped sharks with cameras to map a carbon reservoir half the size of Florida
![An underwater photo of a tiger shark with an orange camera on its side](https://i0.wp.com/www.sciencenews.org/wp-content/uploads/2022/11/111422_no_tiger-sharks_feat.jpg?fit=1030%2C580&ssl=1)
Tiger sharks equipped with cameras (one pictured here) helped researchers map the world’s largest seagrass ecosystem.
Diego Camejo for Beneath The Waves
By Nikk Ogasa
Scientists have teamed up with tiger sharks to uncover the largest expanse of seagrasses on Earth.
A massive survey of the Bahamas Banks — a cluster of underwater plateaus surrounding the Bahama archipelago — reveals 92,000 square kilometers of seagrasses, marine biologist Oliver Shipley and colleagues report November 1 in Nature Communications. That area is roughly equivalent to half the size of Florida.
The finding expands the estimated global area covered by seagrasses by 41 percent — a potential boon for Earth’s climate, says Shipley, of the Herndon, Va.–based ocean conservation nonprofit Beneath The Waves.
![An underwater photo of Austin Gallagher scuba diving just above a field of seagrass](https://i0.wp.com/www.sciencenews.org/wp-content/uploads/2022/11/111422_no_tiger-sharks_inline.jpg?resize=378%2C450&ssl=1)
Seagrasses can sequester carbon for millennia at rates 35 times faster than tropical rainforests. The newly mapped sea prairie may store 630 million metric tons of carbon, or about a quarter of the carbon trapped by seagrasses worldwide, the team estimates.
Mapping that much seagrass was a colossal task, Shipley says. Guided by previous satellite observations, he and colleagues dove into the sparkling blue waters 2,542 times to survey the meadows up close. The team also recruited eight tiger sharks to aid their efforts. Similar to lions that stalk zebra through tall grasses on the African savanna, the sharks patrol fields of wavy seagrasses for grazing animals to eat (SN: 1/29/18; SN: 5/21/19, SN: 2/16/17).