(Image Credit: Shelly Negrotti/AP Photo)

Walter Szulc will likely never forget the first time he went kayaking thanks to the great white shark that appeared directly behind him, trailing his kayak.

"I saw the fin right away and I figured this is it or I'm going to paddle in," Szul said.

It sounds like a terrifying scene right out of "Jaws." Szulc was kayaking 100-150 yards off the waters of Cape Cod, Mass., Saturday when hundreds of beachgoers saw the shark's dorsal fin about 10 feet behind him. People began to point in Szulc's direction while yelling "shark."

A nearby surfer watched in horror as the 12-to-14 foot great white approached. Szulc credits that surfer for saving his life because he was the first person to point out the shark.

"I looked back and that's when the shark was right behind me," Szulc said.

Szulc said he'd reassured his daughter moments before the ordeal that the chance of their seeing a shark was slim to none.

More than 3,000 swimmers at Nauset Beach were asked to get out of the water when the shark was sighted.

"Everyone was very relaxed and the shark put on quite a show moving back and forth out in front of the beach, but it was done in a very orderly fashion," Harbormaster Dawson Farber said.

It was the third great white sighting in Cape Cod in the past couple of weeks. The sharks are drawn to the area because of a huge spike in the seal population, and seals are essentially shark bait.

"The elbow of the cape has these large, dense concentrations of gray seals now, and these white sharks go to the area to feed," said Greg Skomal, a senior biologist at the Massachusetts Division of Marine Fisheries. "Because the seals are so abundant, now the white sharks are paying more attention."

Skomal said the gray seal population off Cape Cod has grown from 10,000 to more than 300,000 since protections were put in place.

Author Jonathan Kathrein, who survived a shark attack, said the fear of sharks is overrated. "The reality is sharks aren't trying to eat people and statistically in almost every shark attack, the person who's attacked survives," Kathrein said.

Across the country off the coast of Santa Cruz, Calif., Rommel Camu, 52, had an even closer encounter with a great white.

"His [Camu's] boat was lifted up by a 14-to-18 foot shark. The boater was then kicked out of the boat and the shark bit the kayak," Sgt. Ester Beckman of the Santa Cruz Sheriff's Department said.

Szulc credits his own survival to instinct.

"I just reacted. I thought it was either it or I'm getting in so I just paddled like no tomorrow," he said. "I kind of ran out of the water like a little child."

ABC News' Olivia Katrandjian contributed to this report.