When a shark emerged from the water with an open mouth and triangular 2-inch teeth, fisherman Steve Clark knew he was having a close encounter with a great white. The chance meeting, he says, happened about 5 p.m. Saturday at 28-Mile Wreck, the site of a World War II shipwreck off of Cape May, New Jersey.

"We were worried that it was going to harm the engine. It started to mouth it, but it wasn't actually biting down," said Clark. "I think it was just feeling it. It was just cool because she stayed around the boat for so long and really let us look at her."

Clark's team of fishermen spotted the 16-foot great white shark swimming toward their 35-foot-boat, the 35 Everglades.

The shark swam around the vessel for about 20 minutes before ripping a chum basket of fish right from the side of the boat -- the only time Clark felt nervous during the encounter. Members of the crew took photos and videos as the shark swam nearby.

"He is gorgeous, or she. It could be a she. Watch out. He could come out. Get back. Get back. You guys are nuts," said a voice on a YouTube video. "Don't get close. It will come up. It will come after us."

Clark, of Avalon, New Jersey, and his friends work with the National Oceanic and Atmospheric Administration (NOAA) to tag sharks in the Atlantic off the New Jersey coast as part of a cooperative initiative called the Apex Predator Program.

A recent study conducted by the NOAA says that great white shark numbers have increased since 2000 due to conservation efforts and grey seals.

Bob Schoelkopf, founding director of the Marine Mammal Standing Center in Brigantine, says the sharks go to where the food is.

"The species appears to be recovering," said Cami McCandless, one of the study authors. "This tells us the management tools appear to be working."

Such a shark sighting is not that uncommon this time of year, according to Clark. He says he usually sees one great white shark every year and is able to differentiate between sharks due to the great white's teeth.

Mark Sullivan of Stockton College says there is clear evidence that their numbers are naturally increasing, but cautions there's no cause for beachgoers to worry.

"You actually have a much better great chance of being struck by lightning than being attacked and killed by a white shark," said Sullivan.

PAST COVERAGE: Great White Shark Spotted Off NJ Coast

Earlier in the day, Clark's crew caught and released a dusky shark that weighed 150 pounds. Shortly after that, they saw another shark and relocated their boat two miles away when the great white came upon their boat.

The day was pretty slow, but seeing the great white shark was a "big bonus," said Clark.

Contact Sarah Glover at 610-668-5580, sarah.glover@nbcuni.com or follow @skyphoto on Twitter.