Photo: Contributed - Great River Fishing Adventure

The father and son duo pose with the giant fish before releasing it.

When 19-year-old Paul Jarvis first caught sight of the fish on his line, he thought it could be a shark.

That's how big the sturgeon was that he caught Thursday in the Fraser River near this southwest B.C. community.

"All of a sudden it jumped out of the water, and I'm never going to forget the way it jumped out," said Jarvis. "It looked like a shark jumping out of the water towards us."

"I was thinking, 'Oh my goodness, this is massive,'" the American tourist said.

The Atlanta, Ga., resident's catch was about 3.5 metres long, and the tour fishing company that provided a guide for Jarvis estimated the animal weighed about 399 kilograms.

Matthew Clive of Great River Fishing Adventures said the catch can't be entered into an official record because that would require the fish to be killed.

Sturgeon are a protected species.

It took about one hour of wrestling with the giant fish before Jarvis could lead it towards a nearby beach.

"I can't explain the pain," said Jarvis of his struggle with the behemoth. "It kills your lower back, it hurts your legs, I'm still kind of sore from reeling it in."

Once the sturgeon was exhausted, Jarvis, his father and their guide jumped out of their seven-metre fishing boat and pushed the fish near the shore, where they measured and photographed it before releasing it.

"It was an experience of a lifetime — it's amazing, I'll never forget that," Jarvis said.