A fight between a harbour seal and giant pacific octopus in the waters off Victoria's Ogden Point on Monday drew a crowd of onlookers.

Bob Ianson was out for a walk with his wife, daughter and grandson and had his camera at the ready when he spotted the seal, wrapped in the tentacles of the octopus.

"It was unbelievable," Ianson said. "That seal is probably, I don't know, four-and-a-half feet long? So that octopus is a pretty big octopus."

Seal showing off , said observer

Ianson said the fight drew a crowd of several dozen people, and was just a metre or two offshore.

"It was almost like the seal was bringing the octopus up the surface to show off what he had," he said.

The photos are rare, but the fight isn't, according to the Vancouver Aquarium.

"Octopus is a regular part of the harbour seal's diet," said aquarium research biologist Chad Nordstrom. "Actually capturing it on film is the rare thing."

Not the first fight

The aquarium had only one photograph of a fight between the two animals, taken by a diver many years ago, Nordstrom said.

The octopus in question is an adult giant pacific octopus, which usually grow to be about 15 kilograms, but can be much larger.

This was the second octopus/harbour seal encounter to be captured at Ogden Point. The first was a video taken two years ago.

Meanwhile, Bob Ianson is thrilled with the attention his photos have received, and is happy he recorded the memory for his two-year-old grandson, who picked an inopportune time to take a nap.

"My daughter leaned down to tell him, 'look at the seal' as his head hit the side of stroller. He was absolutely passed out. He missed the whole process."