Carolinas’ top shark expert publishes new guide to sharks, skates and rays

By DAVID WILLIAMSON
UNC News Services

CHAPEL HILL -- When Dr. Frank Schwartz, a University of North Carolina at Chapel Hill faculty member, discusses shortspine spurdogs, roughskin spurdogs, bigeye threshers, porbeagles and dusky smooth hounds, he’s not talking about man’s best friend.

Instead, those are all common names for sharks of the Carolinas -- denizens of the deep far more likely than dogs to scare the wits out of beachgoers and far less likely to bite the unwary.

A professor at UNC’s Institute of Marine Sciences in Morehead City, Schwartz has studied fish and other marine creatures for more than 45 years and is widely regarded as one of the leading experts on sharks in both the Carolinas and nationwide. Author of 400 scientific papers and four books, the New Castle, Pa., native is also the author of a new illustrated guide just published by UNC Press, "Sharks, Skates and Rays of the Carolinas," his third volume on the subject.

Mostly, Schwartz has worked and taught students at the institute, but twice a month for more than three decades, he has boated into the Atlantic off Shackleford Banks for a full day to catch, tag and then release sharks. He still goes to his office at 4 a.m. each day, even he when he plans to head out to sea for the day.

"We’ve done this year in and year out to monitor the state’s shark populations -- to learn what’s out there and how those populations might change over time," Schwartz said.

Some worry that the world’s shark populations are disappearing, but based on his experience in the Carolinas, the UNC biologist cannot agree.

"Shark populations will continue to wax and wane," he said. "After 35 years of fishing the same areas off Morehead City, using the same gear, from April to November, I have observed that our shark populations other than the dusky shark are stable or increasing."

He and his students lay out two three-mile long buoyed lines running east-west in shallow water and north-south in deep water. The fishers use scores of baited hooks, catch the fabled predators and, after recording their size, sex and species, release them unharmed.

Sharks, he said, are known in scientific language as Squalomorphii, a form of elasmobranch. Skates, rays and sawfish are called Rajomorphii, or batoids, and are also elasmobranches. What they have in common, among other characteristics, are skeletons composed of cartilage rather than bone. They predate modern humans by some 400 million years.

Schwartz’s new 184-page book will serve as an inexpensive, illustrated guide to the 91 species of sharks, skates and rays that inhabit the estuaries and ocean waters east of the sister states. The $15.95 paperback offers a glossary, references and dichotomous keys to enable almost anyone to identify unknown specimens.

Almost a full page, complete with line drawings, is devoted to each of the creatures, which range from the scary great white shark to the goofy-looking white-saddled cat shark to the bizarre and frightening great hammerhead. Included are 16 color photographs of sharks, some of which are hazardous to humans.

In the Carolinas, he and others have observed sharks ranging from a few centimeters in length to about 40 feet. That latter specimen, seen near the Cape Fear River mouth near Wilmington in 1934 was a whale shark -- not only the largest shark ever recorded, but also the biggest fish.

Especially dangerous – potentially -- are the tiger, bull, mako, dusky, blue, blacktip, great white and hammerheads, Schwartz said. But attacks are rarer than bites from humans.

"North Carolina has had 23 authenticated shark attacks between 1870 and 2002," he said. "Most were caused by bull sharks, although three of the five attacks in 2000 were caused by blacktips."

What causes shark attacks?

Although not proven, suspected factors include warmer water, bright swim suits, cloudy water and burgeoning numbers of beachgoers in their territory.

"Analyzing the shark attacks that have occurred in Pamlico Sound or the ocean off North Carolina from 1870 through 2002 reveals a remarkable correlation of factors when each attack occurred," Schwartz said. "Twenty incidents occurred in the afternoon during ebbing tides during full or dark phases of the moon, regardless of whether the attack took place in the ocean or in Pamlico Sound." Two others happened when coastal winds made the water behave as if the tide were ebbing.

The scientist urged caution when swimming in or scuba diving in water warmer than 81 degrees C during July and August and during full or new moons and during ebbing tides.

"Do not swim at night or in the early morning or evening, periods when most sharks are feeding," he said.

A member of UNC’s College of Arts and Sciences, Schwartz is curator of the state’s fish collection, now housed in Raleigh and totaling 500,000 specimens, most of which he gathered.

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Note: Schwartz can be reached at (252) 726-6841 in Morehead City.

UNC Press Contact: Gina Mahalke, (919) 966-3561, or gina_mahalek@unc.edu
News Services Contact: David Williamson, (919) 962-8596