Tracking a Great White Shark Off the Jersey Shore

By Lauren Wanko

Meet Mary Lee — a great white shark tracked along the East Coast since 2012. This week she cruised past the Jersey Shore.

“Since 2012 she’s moved about 2,000 miles and has really made a lot of movements between Cape Cod and North Florida,” said University of North Florida Associate Professor of Biology Jim Gelsleichter.

Ocearch — a non-profit dedicated to researching great white sharks and other large apex predators — captured and tagged the female near Cape Cod three years ago.

“The way that it works is the shark is baited towards the boats, hooked using a smaller vessel and then that vessel brings the shark to the mother ship, the Ocearch itself,” Gelsleichter said.

The shark is guided by hand on and off a 75,000 pound custom lift. A towel’s placed over the eyes to protect them from the light and keep her calm. A hose with running sea water is placed in the shark’s mouth so water can pass through the gills to keep the shark alive.

“From there we’ve got about 15 minutes to work with the animal to implant a number of tags that provide us with both short-term and long-term information about movement patterns,” Gelsleichter said.

Researchers also draw blood to identify what the animals feed on and their breeding behavior, among other things. Gelsleichter uses an ultrasound on the females to better understand their reproduction. When she was tagged, Mary Lee was 16 feet long, weighing 3,000 pounds. Gelsleichter says she’s bound to be bigger now. She was named after the expedition leader’s mom. Her movements or pings are posted on Ocearch’s Shark Tracker in near real time.

“These sharks are tagged with very high quality satellites, real time tags, kind of like a GPS. These tags when the shark surfaces sends signals to satellites that allow us to zero in on their positions. Just like a GPS, the longer the animal stays at the surface the more satellites will communicate with it so we’ll get a better position of that animal,” said Gelsleichter.

Five mature females have been tagged along the East Coast. Researchers hope to also tag a male.

Gelsleichter calls this the Golden Age of white shark research on the East Coast. He says researchers are only now getting a better understanding of where the animals are going — often back and forth between Florida and Cape Cod within the same season. He hopes their studies will help shed light on why the sharks chose to travel to specific areas along the coast.

In recent years, there’s been growing support to protect the great white shark and a deeper appreciation for the magnificence of the animal, insists Gelsleichter. Mary Lee’s become a celebrity of sorts with fans and followers who will be tracking her every move.

You can follow Mary Lee on Twitter — @MaryLeeShark.