A Palmerston North teenager has told how he was attacked by an enraged swan that has been making waves on a city lagoon.

Jake Jackson-Grammer's circuits around Hokowhitu Lagoon were rudely interrupted when he was set upon by a large white swan who had recently relocated to the city from Nelson to breed with a widowed mate.

Conservation biology student Thomas Burns was on hand with his camera, snapping pictures of ducks and other birdlife, when he spotted the mugging early on Tuesday afternoon. His quick camera work made the pages of the Manawatu Standard and since then news of more swan attacks has emerged.

Jake, who kayaks as part of his multi-sport training, was at the southern end of the lagoon when the swan struck.

The 15-year-old Palmerston North Boys' High pupil, who takes to the lagoon water three or four times a week, saw the swan about 100 metres in the distance.

Next thing, it was on the back of his kayak, pulling at his clothing. Under siege, Jake kept calm.

"I just kayaked to the side so I could jump out. It just kept trying to come back and get me. It was scraping me with its claws."

Jake was trying to keep his kayak upright, as he wasn't keen on falling into the murky water.

And Mr Burns helped chase the enraged bird off by throwing something at it, Jake said.

He estimated the swan had a wing span of about a metre, and it left a bruise or two on his back as a reminder not to return to the frisky bird's territory. For the rest of Tuesday afternoon and subsequent kayaks, Jake has kept away from the swan.

"I'll have to stay down the other end."

Previously, the swan had followed his kayak but had not turned violent, he said.

Palmerston North canoe club member Peter O'Sullivan said he and several others had fallen victim to swan attacks.

"It's attacking everyone. It's very aggressive."

The swan was recently introduced to the lagoon by Ken Cook as a partner to a lone female.

He said they had become territorial.