A "virgin" bluewater angler has landed New Zealand's biggest fish yet - a 483.4kg blue marlin - but isn't bothered about a bureaucratic technicality stopping him from claiming it as a record.

"I'm not too worried about this record business - that's their problem really," Whangarei builder Ross Jameson said of International Game Fishing Association rules requiring him to be a member of an approved club before claiming line honours.

Mr Jameson, who reeled in his catch off the tip of the North Island on Thursday, on the eve of the 58th birthday he was celebrating with friends last night on the Bay of Islands charter vessel Harlequin, admitted never having caught a billfish on three previous expeditions.

"We usually go out diving, and snapper fishing," he said last night from off Northland's east coast.

But asked how he would assess his fishing career now, he said: "Well, it certainly got a bit of a boost, didn't it?"

His catch was more than 10kg larger than the next-biggest marlin caught in New Zealand waters, a 473kg black hooked by Alain Jorion off East Cape in 1963, and 2kg heavier than a 481.26kg mako shark hooked by J. Penwarden in 1969.

"It's a once-in-a-lifetime fish, very impressive - everyone up here is really excited," said Houhora Gamefish Club weighmaster Lisa Lilly, who recorded details before Mr Jameson's marlin was sent to a taxidermist in Tauranga to be mounted.

The fish took a pink lure just past the "The Hook", a pinnacle between the northern tip of the North Island and the Three Kings Islands, from the boat Harlequin under the command of skipper John Douglas.

It took just 80 minutes to be landed on the vessel, with others of Mr Jameson's five-member party of "senior gentlemen" pitching in with giant meat-hooks to bring it on board.

"Most people have a blue on for hours [before it is landed]," Ms Lilly said. Fishing guide Chris Ash said it took about 20 minutes longer for the seven on board to heave the fish through the boat's cockpit door from the deck.

"There were seven of us pulling on it," said Mr Ash of Ahipara, who was also a crew member of a boat skippered by his father, Bob Ash, which landed a 456.7kg blue marlin over the "The Hook" in the late 1990s.

He said that fish retained the New Zealand record for a blue marlin caught on a 37kg line, but the fact that Mr Jameson was not eligible to claim a new record was of as little concern to his father as to the latest charter party.

"He doesn't think it matters, he's just rapt that I'm on the boat that did it again - I just told him to move his thing off the wall [of the Houhora Gamefish Club] - we've got a new one to put there."

Mr Ash said he was proud of his charter party, all aged over 60 apart from Mr Jameson.

"I'll tell you what, these old gentlemen know how to gaff a fish all right - they couldn't miss because there was a lot of fish."