SAN DIEGO (USA)- Before dawn last week, the crew of the fishing boat Outer Banks set four miles of long-lines off San Diego Harbor, angling for a good catch of young thresher sharks in hopes of preserving the fishery. Through an annual study, scientists from the National Marine Fisheries Service capture, tag and track thresher sharks —- a popular commercial and sport fish whose numbers collapsed in the 1980s.
After sunrise, the crew pulled in the first thresher. They braced their legs against the rail to steady the shark’s wriggling body and flapping tail as they tagged it. Lowering the glistening female back into the water, researcher Helena Aryafar jotted down notes.
“Condition? Good or excellent?” she asked.
“Very excellent,” said Dan Cartamil, a post-doctoral researcher at Scripps Institution of Oceanography who specializes in thresher sharks.
In a series of cruises that joined bait and tackle know-how with scientific analysis, the team tagged and released 412 thresher sharks over 18 days as part of a nine-year study of the fish, a fish Cartamil said is “the most commercially important shark in California.”
“I like to do it once a year and reconnect with the little baby sharks I haven’t seen in a while,” Cartamil said.
Read more: North County Times