"They are fun. Because they are there and not there," said Schwartz, a marine zoologist who has been a professor at the UNC Institute of Marine Sciences at Morehead City since 1967. He wrote the illustrated guide, "Sharks, Skates, and Rays of the Carolinas," published in 2003 by the University of North Carolina Press.

"I admire them greatly because there are a lot of things we don't know about them," Schwartz said. "For example, we don't know where they mate and how they know when to mate, since the sexes travel separately in schools or alone."

From mid-April through Nov. 1, Schwartz takes students out every two weeks to bait 100-hook long lines off the Beaufort Inlet and seven to eight miles offshore.

"This past Wednesday we got 18 sharks in two hours," he said. "We tagged them. We also caught a female Atlantic sharpnose shark tagged by Virginia people. I reported it to them and then released her with our tag too. When someone else catches her they will report back to both of us."

Every trip is unique.

"We never know what is out there," Schwartz said. "Yet we have learned that there are at least 58 species of sharks off the coast of North Carolina."

He has studied many aspects of shark life including their feeding habits, how they age, and what species of sharks have attacked humans on our coast.

But now he is concentrating on tagging them.

"I want to know how they get from one place to another," Schwartz said. "Do they go offshore, follow a certain temperature or current?"

His research has established what sharks can be found off the North Carolina coast and when.

"For example, in late June and July the hammerhead sharks arrive, the black nose follow and then come the tiger sharks," Schwartz said. Great whites have been documented during April just off Beaufort Inlet.

Tagging sharks has its adrenaline moments, but Schwartz and his assistants have never been injured.

"You do have to be careful of the ones with teeth," he said. "Sharks are not very dangerous. People are going into the shark's domain and not the other way around, and should just use caution when they enter the water. There are sharks off the coast year round."

Former Schwartz student George Burgess, now curator of the International Shark Attack File at the University of Florida's Florida Museum of Natural History, said that in 2008 there were three shark attacks in North Carolina, no deaths. In 2009, there were no attacks.

"Worldwide, 70 to 75 million sharks are killed each year in fisheries and sharks are implicated in, on average, only four human deaths per year, so it is pretty easy to see who is the hunter and who is the prey in this relationship," said Burgess.

Although every human death and injury is regrettable, Burgess said, "we must remember that marine recreation is in fact a wilderness experience and as such we must accept certain risks that accompany any foray into the wild."

Wet wilderness forays are Dan Orr's specialty. Orr is the president of the Divers Alert Network, a nonprofit dive safety organization with more 250,000 members, located in Durham.

Orr has made more than 8,000 scuba dives. Two trips to Guadalupe to see great white sharks are among his most memorable. The area has one of the world's greatest populations of great whites.

Orr's first trip in 2008 to this Pacific Ocean island was organized by the Historical Diving Society and a second in 2009 was sponsored by the Divers Alert Network as a fundraiser.

"There was one cage tied to the stern of the boat that would float on the surface," Orr said. "Divers put on a weight belt, a mask and would have surface-supplied air. You would climb down in the cage and spend as much time there as you wanted."

Another cage held two to three people and was submerged to 40 feet, where one could just sit watching the great whites move slowly around the cage.

"When the cage gets down to 40 feet, the top hatch can be opened and you can stand on top if you want," Orr said. "There is nothing to compare with this experience. It is just awe inspiring. They move slowly and majestically."

Orr, who co-wrote "Scuba Diving Safety," lectures across the country.

"One of my favorite things I say is that more people are killed by falling soft drink machines than by sharks," he said.

"If I am out talking to school kids, like second graders, they ask me if I have ever been eaten by a shark and are disappointed when I say no," he said. "Otherwise people want to know if they are going to be attacked out swimming. The answer is no."

Orr's first encountered sharks as a swimmer on the aircrew rescue team in the U.S. Navy and while in the Philippines snorkeling. "I was absolutely fascinated," he said.

The fascination has never wavered. "I have this feeling every time I see them," he said. "There is nothing to compare with this experience."