Scientists have teamed up with tiger sharks to uncover the biggest expanse of seagrasses on Earth.
A large survey of the Bahamas Banks — a cluster of underwater plateaus surrounding the Bahama archipelago — reveals 92,000 sq. kilometers of seagrasses, marine biologist Oliver Shipley and colleagues report November 1 in Nature Communications. That space is roughly equal to half the scale of Florida.
The discovering expands the estimated international space coated by seagrasses by 41 p.c — a possible boon for Earth’s local weather, says Shipley, of the Herndon, Va.–based mostly ocean conservation nonprofit Beneath The Waves.
Seagrasses can sequester carbon for millennia at charges 35 instances sooner than tropical rainforests. The newly mapped sea prairie might retailer 630 million metric tons of carbon, or a couple of quarter of the carbon trapped by seagrasses worldwide, the staff estimates.
Mapping that a lot seagrass was a colossal job, Shipley says. Guided by earlier satellite tv for pc observations, he and colleagues dove into the glowing blue waters 2,542 instances to survey the meadows up shut. The staff additionally recruited eight tiger sharks to help their efforts. Just like lions that stalk zebra by means of 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).
“We wouldn’t have been in a position to map anyplace close to the extent that we mapped with out the assistance of tiger sharks,” Shipley says.
The staff captured the sharks with drumlines and hauled each onto a ship, mounting a digicam and monitoring gadget onto the animal’s again earlier than releasing it. The sharks have been sometimes again within the water in below 10 minutes. The staff operated like “a NASCAR pit crew,” Shipley says.
Researchers had beforehand urged monitoring seagrass-grazing sea turtles and manatees to find pastures. However tiger sharks have been a wise alternative as a result of they roam farther and deeper, says Marjolijn Christianen, a marine ecologist at Wageningen College & Analysis within the Netherlands who was not concerned within the new work. “That’s a bonus.”
Shipley and colleagues plan to collaborate with different animals — together with ocean sunfish — to uncover extra submarine meadows (SN: 5/1/15). “With this [approach], the world’s our oyster,” he says.