Somehow, Tyler Macallister wasn’t worried about becoming shark bait as he hovered nine feet above one of the most formidable predators in the ocean with only a metal railing between him and a great white.

The Mattapoisett Selectman and captain of the commercial fishing boat, F/V Cynthia C, was about six miles southwest of Provincetown when he and his first mate, Todd Espindola, spotted a female great white shark on June 23.

Measuring 17 to 18 feet long and around 10 feet wide, Macallister thought the animal was a basking shark.

When he realized it was a rare great white, he grabbed a camera and started videoing from the end of the 25 foot extension on the front of his boat.

“You don’t see too many white sharks that big,” said Macallister. “Several times she would just roll up on her side so she could get a real good look at what was going on. It was an amazing thing.”

As a fisherman for almost three decades, Macallister said he wasn’t worried that the shark would turn his fishing trip into a scene from "Jaws."

“I’ve seen pretty much everything that swims in the Atlantic Ocean,” he said. “When it comes to sharks, you can tell when they’re going to become aggressive.”

Two years ago, Macallister saw a 12-foot male great white that he described as “stiff and aggressive and posturing.”

“This animal,” he said, “just the opposite. She was calm. She knew that she was the apex predator.”

Macallister said she cut through the water without a ripple as the F/V Cynthia C moved slowly through the water.

“After about 10 minutes, she just slowly sank out of sight,” he said. “We watched her disappear into the depths.”

Consulting with friend and shark biologist John Chisholm, Macallister found out that the expert had only seen about two similarly sized great whites in the past ten years.

The extended footage of the shark gave scientists enough information to recognize it for future sightings, said Macallister. He also said the shark had not been cataloged before, and was named Miss Alexandra after his daughter.

The growing seal population in the area has lead to an increase in the shark population as they seek the food source.

For his part, Macallister is happy he was in the right place at the right time.

“I could have been going one more knot faster or one knot slower and I wouldn’t have seen her,” he said.

Macallister has videos of the shark on the F/V Cynthia C Facebook page.

“The whole idea was this really could help people look at this animal and how majestic it was that day,” he said.