With the help of over 50 researchers from more than 20 institutions, the non-profit Ocearch has tagged and tracked sharks around the world, from South Africa to the Galapagos. In September 2012, this research mission came to New England for the first time when the great white shark dubbed “Genie” was tagged off of Chatham in Cape Cod, MA.
What does it take to wrangle one of the fiercest apex predators in the ocean? After hours of preparation, sport fishermen and scientists from Ocearch set out each day on the repurposed crab vessel M/V Ocearch, a boat about the same size as the sharks they’re searching for, and use chum to attract sharks while they scan the ocean surface.
Once sighted, a shark is baited and hooked, guided towards the Ocearch vessel, and hauled out of the water using a custom lift capable of supporting thousands of pounds in weight (great whites can weigh over 5,000 lbs). The Ocearch captain jumps into the water and onto the platform with the shark and uses the shark’s tail helps to guide it onto the lift.
When the team pulled Genie on board and the water around her receded, her anxiety visibly increased, so Ocearch Captain Brett McBride threw a wet towel over her eyes. As she began to calm down, the Captain was able to remove the hook from her mouth and insert two hoses to cascade water over her gills. At this point the rest of the crew jumped onto the platform, sporting jeans and long-sleeve shirts, and began to take a series of measurements and tag Genie. Named for “the shark lady” Eugenie Clark, Genie measured at 14 feet, 8 inches and 2,292 pounds.
Using a power drill, Genie’s dorsal fin was fitted with a satellite tag, an accelerometer and an acoustic tag. Other researches collected blood and tissue samples to study back in the lab. Genie was out of the water for approximately 15 minutes before she was guided back into the ocean and the tracking began. 10 hours later, the accelerometer detached from Genie, floated to the surface and transmitted data regarding her swimming pattern and movements. Whenever Genie’s dorsal fin breaks the surface, her tracker transmits a signal to a satellite overhead, which produces an estimated geographical location for the shark. Where is Genie now? Enjoying herself on Virginia Beach, VA.
As of this summer, the “shark wranglers” working for Ocearch have successfully tagged well over 50 great white sharks around the globe. By tracking sharks like Genie, researchers are hoping to build an understanding of their migratory patterns, breeding grounds, birthing sites, feeding areas and general white shark behavior. This information will help protect some very important animals—great whites are apex predators, which means a healthy population is crucial to maintaining the balance of ocean food webs and ecosystems.