He and another marine researcher quickly lasso the tail of the sharp-toothed female to the side of the boat and hold it steady as they take tissue samples and work to attach small data collection devices. Metzger marvels as the shark's thick, rugged skin snaps a surgical-grade scalpel.

"It's no surprise that they've been around since prehistoric times and they're still going strong," Metzger says as he stitches up the incision and sends it along its way.

Metzger and other researchers are catching, tagging and releasing a wide range of sharks as they seek to understand the local population and shed more light on one of the world's few confirmed great white shark nurseries, where masses of young predators spend their first vulnerable years feeding and growing. Other white shark nurseries recognized globally are in the coastal waters off California, Mexico and Australia.

"It's that initial fear of sharks that captures people's imagination," said Metzger, who also teaches marine science at Southampton High School. "Hopefully, through educational opportunities like today, we'll be able to show that these sharks are far from mindless eating machines."

Warmer waters are drawing tropical sharks north

The researchers attach different types of tags. One relays location by sending an acoustic signal that can be detected by monitoring receivers set up along the coast. Another measures depth and water temperature for several months, then pops off.