A Saltspring Island man attacked by a bear in his boat was "protein", says the man who led the fight that killed the bear.

"The bear wanted him, he was going to eat him," Bruce Miller, 40, said yesterday. "The bear needed protein and this guy was it."

Miller was aboard his boat moored to a Port Renfrew jetty at 5 p.m. Tuesday when he spotted the bear run up an adjacent jetty and jump into 52-year-old Blain Pharis's boat.

The bear ignored the coho salmon that Pharis threw toward him and instead jumped at the man. After hearing Pharis scream, Miller picked up his metre-long spiked gaff -- used to pull fish out of the water -- and dashed toward the victim.

"He was pinned on the floor, the bear had a good hold of him and was biting and shaking him," Miller said. "I figured he was dead in seconds."

Miller heaved his gaff and sunk its five-inch spike into the bear's neck. "It went right in and the bear still wouldn't let go."