If you caught one of Ethan Daniels’ lectures during his book tour for Under Cape Cod Waters last week, you probably remember the chilling story of the day he photographed the shipwrecks off the coast of Chatham.  Heading out on the dive boat, Daniels remembers seeing a “stick” boat about a mile away, with a spotter plane just above. Unbeknownst to Daniesl, aboard was Dr. Greg Skomal and captain and harpoonist Bill Chaprales, who were tagging five great white sharks.  Lucky for him, Daniels was forced to stay under water to decompress—confronting the idea of several angry real-life “Jaws” just a short swim away.

On Monday night at the New England Aquarium, a packed house of anxious Cape lovers had the pleasure of hearing this same story through Dr. Skomal’s eyes. Skomal assured his audience that although he believes the great whites spotted last Memorial Day Weekend off Chatham are resident sharks, the general public need not panic. Skomal associates the increase in great whites directly with the increase in grey seals on our shores, and assures everyone that if you use some common sense and stay away from the seals, you wont become shark bait.

By tracking the great whites that originated in Cape Cod waters last summer, Skomal and his team learned that the sharks travel along the Atlantic Coast, venturing just south of Jacksonville, Florida (home of a right whale sanctuary) in winter months. Skomal also studied the water depths and temperatures that the sharks swim in—finding far less of a variance than he ever imagined—rarely diving deeper than 150 feet below the surface and staying within a very narrow range of 59- to 67-degree waters.

There is an upshot to Cape Cod seeing great whites once again, because they play a vital role in the food chain. “It’s a good sign that the Atlantic’s apex predator is back in the region.  Knowing the sharks are out there may make surfing and diving a bit more exciting but the shark population indicates that the ecosystem is in decent shape,” says Daniels.

To get a look at what else lives below Cape Cod waters, check out Ethan Daniels’ photography in Under Cape Cod Waters.