by Kristen Minogue
In the coastal waters of the mid-Atlantic, an endangered shark is making a comeback. Led by former Smithsonian postdoc Chuck Bangley, scientists at the Smithsonian Environmental Research Center (SERC) tagged and tracked nearly two dozen dusky sharks over the course of a year as part of the Smithsonian’s Movement of Life Initiative. They discovered a protected zone put in place 15 years ago is paying off—but it may need some tweaking with climate change.
Dusky sharks are what Bangley calls “the archetypal big, gray shark.” Born three feet long, as babies they’re already big enough to prey on some other shark species. But they’re slow growing. It can take 16 to 29 years for them to mature. If their populations take a hit, recovery can take decades.
The sharks’ numbers plummeted in the 1980s and 1990s, when well-intentioned managers offered sharks as an “alternative fishery” while other stocks, like cod, were collapsing. The overfishing that followed wiped out anywhere from 65 to 90 percent of the Chesapeake’s duskies, said Bangley, now a postdoc at Dalhousie University in Nova Scotia. Managers banned all intentional dusky shark fishing in 2000. Five years later, they created the Mid-Atlantic Shark Closed Area encompassing most of the North Carolina coast. The zone prohibits bottom longline fishing, which can accidentally ensnare dusky sharks, for seven months of the year.
But is the partial refuge working?
